40 ELECTRONICS - Whitsunday Discount Marine...10 DIY TECHNICAL HELPLINE — It’s FREE Technical...

DIY boat owner 2005-1(www.diy-boat.com) 1-888-658-2628

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CONTENTS 2005-1DIY boat owner 2005-1www.diy-boat.com 1-888-658-2628

Columns

8 SCUTTLEBUTTAll that Shines is Not Always Stainless:When selecting stainless steel fasteners,knowing which alloy to select for useabove and below the waterline can savesome maintenance headaches. By Patricia Kearns

40 ELECTRONICSCommunication Breaker: When you getyour ship together, make sure you’ve doneall the paperwork to make your VHFmarine radio, EPIRB and SSB legal. By Janet Ross

42 ENGINESCorrosion Protection: Knowing what caus-es corrosion and how to test for it willensure your sterndrive unit is protectedfrom being eaten by corrosion’s effects. BySteve Auger

56 BOAT HANDLINGSeamless Integration: Just as a footballteam huddles before each play, a skipperand crew should develop a game plan fordocking or anchoring. By Peter Pisciotta

58 PROJECTSTeak and Holly Flooring; Like-NewCoaming Boxes; Custom Switch Labels

64 VIEW FROM THE STERNWill that be Hard or Soft?: Some boatsride hard, others give a softer ride. Whichtype of bottom is best depends largely onwhere you go boating. By Roger Marshall

2 CURRENTSLetters, News, Wanted

10 TALKBACK Q&A Questions from DIY Readers

10 DIY TECHNICALHELPLINE — It’s FREE

Technical Help with your subscription. Seeinsert on page 49 or log onto DIY ONLINEat www.diy-boat.com

17 20 TIPS TO HELP WITH PAINTING JOBS

48 PRODUCT INFO CARDTo receive information on boating productsand enter to win a 3M DECK & HULLCLEANER—just log onto www.diy-boat.comand click on “Product Info.”

Departments

7Easy Rope-to-ChainSplice for Windlasses

18 Bad VibrationsHere’s how to diagnose problems and the stepsneeded to maintain, repair or replace bearings,propellers, shafts and struts. By Nick Bailey

24Fuel Cell Power Imagine having a clean and quiet source of12-volt power available 24/7 anywhere youchoose to cruise. Imagine no longer — fuel celltechnology has arrived! By John Payne

27Fuel FiltrationA well-engineered fuel system involves theonboard cleaning, filtration and transfer of fuel.Improve your boat’s fuel system and keep yourdiesel engine humming with these simple do-it-yourself upgrades. By Peter Pisciotta

32 Cabin VentilationGood condensation appears on the outside ofcold beverages. Bad condensation leads tosoggy potato chips, wet bunks, musty air andwith time, mildew, mold and corrosion. That’swhy every boat owner should know how toeliminate the “bad” by improving onboardventilation. By Sue Canfield

45Prime CoatsFollow these steps from the pros to preparesurfaces for painting, to apply antifouling toaluminum, fiberglass and steel boats andunderwater running gear, to varnish or oilbrightwork and to refinish interiors, aluminumfittings, bilges and vinyl cabintops.

53 The Trim TruthBalancing trim involves rearranging gear,adding stern wedges or installing trim tabs.Here’s how. By Roger Marshall

WIN — 3M MARINE DECK & HULL CLEANER

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Positive Feedback “After running about six hours with hatch-es open, the sooting is much less and alsoit's now a dust as opposed to a thin blacktar-like stain. I think you have probablysolved the mystery. I will continue to runthe engine with the hatches open for theshort term until sooting diminishes. I'llalso check and clean out the elbow andexhaust system if necessary and installproper ventilation. The engine was pro-fessionally installed by a Yanmar dealerand two more Yanmar-certified mechan-ics took more of my money before youdiagnosed the problem. I hope to remainforever soot free and forever a subscriberto DIY.” Comments from Bill Shenko, Jr.of Estero Island, Florida, who contactedDIY's Technical Helpline for help with asooting engine problem and DIY dieselengine advisor Bob Smith provided asolution. For the complete engine analy-sis see "Talkback," on page 16 in thisissue.

In Search of Window Frames Do you know of any suppliers of cus-tom-made, add-on frames as describedon page 22 of Nick Bailey's article onleak proofing cabin windows in DIY2004#1 issue? I've had no reply frommy email to Beclawat or any luck withInternet searches. Al Kirk, Salt Spring Island, British Columbia

Nick Bailey answers: The add-on framepictured on page 22 was supplied byEngineered Marine Solutions, a smalloutfit started by a Lake Ontario boatowner who felt there had to be a bet-ter way to seal and secure bonded win-dows. This style of external frame has

been successfully installed on manyboats. Contact Dan Boisvert at519/404-0267 or email at [email protected]. He has tem-plates for some models but you mayhave to provide templates for your boat.Beclawat now only supplies commer-cial users. It hasn't made small boatwindows in many years but replace-ment gaskets are available from after-market suppliers.

Weather Resources DIY reader Chip Lohman in Woodbridge,Virginia, sent us this list of Internet marineweather resources. They're just a click away!NOAA: www.nws.noaa.gov/om/marine/marine_map.htm; NOAA buoy reports:www.ndbc.noaa.gov/; Wave watch: //polar.ncep.noaa.gov/waves/main_int.html;Weather models: //weather.unisys.com.

How-to SeminarsI attended Jan Mundy's “How to RepairFiberglass Boats” seminar and I must tellyou, I was not expecting it to be thatgood. Jan did an excellent job. It was byfar the best boat show seminar I haveattended. Only wish I had a recorder.George and Mary Marasco, Wyoming, Delaware

DIY editor Jan Mundy presents seminarson various maintenance topics at boatshows where DIY exhibits. For a com-plete list of go to www.diy-boat.com andclick on “Events/Seminars.” FYI: Sorry,but we don't permit recording of ourseminars.

Tips from a SkilledWrapper In the article titled, “ShrinkwrappingAfloat,” in the DIY Projects column in the2004-#3 issue, the author shows usingthe torch inside the wrap. This is illadvised due to the potential to set fire tothe plastic from the heat retained underthe plastic. A heat gun produces about300,000 BTUs, about five times the out-put of an average house’s furnace, andthe heat buildup is very fast. The volumeunder the plastic is a fraction of the vol-ume of an average house. The heat reten-tion pre-heats the plastic making unin-tended holes a problem. If shrinking isdone inside the plastic, and the flamegets close to the webbing tape, fragmentsflare off causing holes along the tapeline.

Materials, like felt under a pad and carpet,used to pad sharp edges have a flashpoint far below the plastic and burn farmore easily causing holes and increas-ing potential for fires. Additionally, a by-product of burning propane is water thatwill condense on the inside of the plas-tic making repairs very difficult. The adhe-sive repair tape will not adhere if theshrinkwrap film has any moisture on itat all. I have found that, due to the stat-ic charge on the shrinkwrap film, dirt iseasily attracted to it. Care needs to betaken not to let the film get dirt on it bytouching the ground. The dirt particlesabsorb the heat and makes pinholes thatmust be taped over. Don't wait too longto shrink the plastic after laying it overyour boat as air born dirt accumulatesand makes shrinking a real problem. Itmay be necessary to wash the film beforeshrinking if dirt accumulates on the sur-face of the film.Rex Miller, Mundelein, Illinois

CurrentsEdited by Jan Mundy

This is a million dollar question with nodefinitive answer. To protect gelcoat fromoxidation you would apply a wax butwax a deck and you lose the skid-resist-ant properties. To remove oxidation,compound the non-skid areas with amild rubbing compound followed by afinishing glaze, such as 3M Finesse-it II.These products don’t contain any sili-cone, wax or UV inhibitors to block thesun's rays that cause the gelcoat to oxi-dize. Once completed, the non-slip willbe glossy but not slippery. Wash the sur-face with boat soap to remove anyresidue and the non-slip will still beeffective. A skid-resistant deck with asplatter-like pattern is more difficult tomaintain due to its irregular surface. — Nick Bailey

How best to protectnon-skid, the molded-ingelcoat type, from oxidizing?

http://www.nws.noaa.gov/om/marine/marine_map.htm

http://www.ndbc.noaa.gov/

http://polar.ncep.noaa.gov/waves/main_int.html

http://weather.unisys.com

http://www.nws.noaa.gov/om/marine/marine_map.htm


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Mike Stenburg of Dr. Shrink replies: I agreewith what this reader says. It's muchharder to shrink from the inside andthere are greater chances for holes tomelt the plastic when heat rises to thetop of the cover on the inside. Any directheat applied to vinyl-covered lifelinesand the woven cord strapping used forsupport structures can easily cause dam-age. More importantly, the heat tool canuse up most of the oxygen under thecover, which is an asphyxiation hazardto the person doing the shrinking or any-one else within the cover. It’s safer toshrink from the outside.

Mandatory BoatCertification by '07Effective the with 2007 model year, theNational Marine ManufacturersAssociation (NMMA), the leading boat-ing industry advocacy association in theU.S., requires that all NMMA memberboat manufacturers have boats NMMACertified to American Boat and YachtCouncil (ABYC) standards. This certifi-cation program also requires participantsto institute a Customer Satisfaction Index(CSI) program.

There arecurrently 140boat manufac-turers partici-pating in theNMMA certifi-cation pro-gram, repre-

senting 75% of all boats produced inthe U.S. each year. The goal ofNMMA, ABYC and the United StatesCoast Guard (USCG) is that all boatmanufacturers be NMMA certified.(Presently, boat builders can elect tocomply with the voluntary ABYC stan-dards.) Only NMMA-certified boats areallowed to display the NMMA Certifiedlabel.

What does this mean to new boatbuyers? Purchasing a boat that is cer-tified as built and equipped to the

accepted ABYC safety standards pro-vides at least a minimum quality con-fidence level to buyers who are tryingto make comparisons in both safetyand value. What it does not mean isthat a boat builder who is not anNMMA member is automatically notincompliance. There are very consci-entious boat builders who are fullycompliant with the USCG and ABYCstandards but they are not affiliatedwith NMMA. This can be confusing tothe boat buyer so it’s important for boatshoppers to be informed about thesafety issues at stake. (Ed: For moreinformation on marine certification andwhat it means to consumers refer tothe “Scuttlebutt” column in DIY 2004-#3 issue.)

Boat Warranties: BuyerBeware Further to the article titled, "BalancingBoat Warranties," in DIY 2002-#1issue, we received this let-ter from a DIY readerdetailing his experi-ences and difficulties inreceiving warranty cov-erage. His case con-trasts sharply to theguidelines provided by authorNick Bailey. To aid other boatbuyers we have published it in its entirety,except to change the actual names of theboatbuilder and boat model.

In Nick Bailey’s excellent article on boatwarranties he points out how boat man-ufacturers pass the warranty buck backto the makers of “all the installed equip-ment, engine, gen-set, steering and con-trol systems….” By making careful notes,doing no repairs oneself, and including theselling boat dealer in the process, Nicksuggests new owners can get warrantyservice. His “it can be fixed if you docu-ment and calmly present the claim”approach didn’t work for me. Boat own-ers should be aware that some manufac-turers will totally disregard a warrantyclaim, government regulations are vagueand government agencies are of little help.

I purchased a new sportfishing runaboatmade by ABC built in North Carolina. Thehull is foam covered roplene plastic, whichhas a feel similar to Tupperware. I decid-ed to buy the boat on the basis of printedadvertisements and salesman statements.

Little did I realize I was about to receivean education in warranties, Coast GuardCertification and the Florida and NorthCarolina Consumer Protection business.

When it became clear my boat manu-facturer wasn’t going to fix the many prob-lems, I did some research to find out howa manufacturer can be made to recalldefective products. In the United Statesthere is a Federal law called theMagnuson-Moss Warranty Act, which out-lines manufacturer warranty requirements.The law is cited as Title 15 Chapter 50United States Code Sections 2301-2312.

Warranty words have developed froma long history of merchandise peddling.One such word is “merchantability,” mean-ing the product is marketable, that it will

perform the basic task/serv-ice/use it is presented and

advertised as being able to do. Inmy case, it means my new boat

should float and do everythinga regular boat is thought to do.Another warranty word is

“express or written warranty.” By way ofexample, the basic purpose of a screw-

driver is to turn screws saying nothingabout its ability to withstand the rig-ors of saltwater exposure. A screw-

driver claimed by the manufacturer to be“zinc coated for marine use” has anexpress warranty. Another warranty wordis “implied warranty.” Warranty lawincludes a concept attaching legal eco-nomic liability on the part of a salesper-sons and boat dealer when a customerrelies on the subject matter knowledge ofa salesman in determining which prod-uct will meet his/her expressed needs.Manufacturers try to guard themselvesagainst the implied warranty claims ofsalesperson that would close a deal byclaiming that nice new boat not only floatsbut also indeed flies!

Written and unwritten product market-ing claims are all enforceable in the U.S.through civil and sometimes criminalcourts. New boatowners can hire lawyersasking a judge to order their boats fixedand for payment of all legal fees. Newboatowners can also attempt to interestthe various state consumer affair officesfor help. Those offices may bring suit toprotect against unscrupulous merchants.The state becomes most active in cases

CURRENTS

If your diesel engine runs at idle with-out smoking but then blows out lots ofblue smoke and soot at cruising rpm,say 2,000 rpm, guess what? It's timefor an injector rebuild!

TIP: Smoking Bad Time


Publisher & Editor: Jan MundyVP Sales & Marketing: Steve KalmanDesigner & Illustrator: Joe VanVeenenWebmaster: Jeff KalmanCirculation: Britton HardyCopy Editing: Patricia KearnsTechnical Advisor: Recreational MarineExperts Cover design: Joe VanVeenen. Inset photocourtesy of Bennett Trim Tabs. Contributors: Steve Auger, Nick Bailey,Bob Smith, Susan Canfield, Peter Caplan,Roger Marshall, John Payne, Peter Pisciotta DIY boat owner™ and The MarineMaintenance Magazine™ are registeredtrademarks of JM Publishing. DIY boatowner is published quarterly by JMPublishing. ISSN 1201-5598While all precautions have been taken toensure accuracy and safety in the execu-tion of articles, plans and illustrations inthis magazine, the publisher accepts noresponsibility for accidents, materiallosses or injuries resulting from the useof information supplied in these articles,plans or illustrations. All rights reserved.No part of this magazine may be reprint-ed or used without the express writtenconsent of the publisher.

CURRENTS

of out and out fraud. The Magnuson-MossWarranty Act also defines “deceptive war-ranty” in part as a written warranty whichcontains an affirmation, promise, descrip-tion or representation which is either falseor fraudulent, or which, in light of all ofthe circumstances, would mislead a rea-sonable individual exercising due care.This sentence is most important. It’s thelegal standard a boat owner must provein order to prevail in court — that youwere a “reasonable individualv who took“due care” to ask questions and look overthat boat yet were “mislead.”

Numerous problems existed with myboat, the major one being water seepinginto and filling up the bilge. The boat wasnearly 30% heavier than the advertisedweight. Some other problems existedincluding hinges tearing off and seat lidspulling out the first use, battery box inca-pable of draining seawater, and trailer thatneeded rebuilding by its manufacturer (nohelp from the dealer) so I could tow theboat home. My complaints to the builderwere straightforward: a lack of mer-chantability, as a boat should float andthis one did not; deceptive advertising asa boat advertised to weigh 635kg(1,400lb) should not weigh 1,088kg(2,400lb); and the boatbuilder’s refusalto comply with the Magnuson-MossWarranty Act by ignoring my many lettersdemanding a replacement hull.

Lessons learned include not buying aboat at a boat/sportsman show, hundreds

of miles away from home, without firstvisiting the dealership. I was later to learnthat this business was not an authorizedoutboard dealer and had neither qualifiedservice nor rigging technicians.Unfortunately, at that time I didn’t evenknow what “rigging” meant. The dealersimply provided me with the boat andtrailer manufacturers’ phone numbers. Ididn’t even know what a “sea trial” wasuntil I was on one but it’s a good thing Iwent for the ride. The throttle controls hadbeen improperly connected and slipped

Marine engine technicians use twodescriptions for engine computers inelectronic fuel injection (EFI) outboardsand sterndrive engines; namely ECUand ECM. According to Steve Auger ofMercury Marine, who is also DIY'sengine advisor and a regular contribu-tor, the difference is just a technicali-ty. The designations are simply themeans for techs to distinguish an out-board from a sterndrive computer.Outboards have an Electronic ControlUnit (ECU), as these engines were thefirst to get EFI and ECU was the com-mon term back in the late 1980s.When Mercruiser engines finally gotEFI, five years after outboards, the termhad evolved to Engine Control Module(ECM). They both perform the samefunction of measuring the airflow of theengine and then injecting the correctamount of fuel to achieve an air to fuelratio of approx 15:1.

Engine ComputerNomenclature

Sac

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DIY boat owner 2005-1(www.diy-boat.com) 1-888-658-2628 5

to the point of loss of most power. As DIY has reported, therewas no written material provided with the boat to help with fur-ther rigging, maintenance or service. This information can beimportant. For example, hull registration numbers won’t stickto the side of the super slick plastic hull without the use of atorch. At least this much information would have been useful.

A generic owner’s manual, produced by the National MarineManufacturers Association (NMMA), was the only documenta-tion provided. This booklet indicates the International Organizationfor Standardization (ISO) directive 10240 requires specific infor-mation be provided and that American Boat and Yacht Council(ABYC) Technical Information Report T-24 recommends addi-tional data to help the new boatowner service and maintain thevessel. This booklet also states, “The manufacturer may alsoprovide a Construction Standards Statement detailing industrystandards followed in building your boat.” None of that infor-mation was provided.

I did receive a one page limited warranty, which states: “ABCwill repair or replace, at its sole option, any part found by ABCto be defective.” The warranty, as Nick Bailey reported, refersthe new owner to the manufacturers of subcomponents to cureproblems under the warranty programs yet leaving those man-ufacturers unidentified. It specifically claims exclusion of elevenconcerns including liability for “damage from improper trailerissues, abuse, misuse, use without normal maintenance, usein commercial or rental purposes, weight, speed, or other esti-mated performance characteristic, owner inconvenience, improp-er propulsion, canvas, fabric or trim and degradation or otherfailure of the boat’s finished surfaces,” and more. Non-warran-ty declarations are the manufacturers’ best-case scenario fordefense of legally imposed liability to warranty products. DIYreaders should know that just because the boatbuilder says itwill not be responsible for problems they created or installeddoes not necessarily make it so. It just won’t happen without alawsuit.

Winning in court is hard work and while one doesn’t plan onhaving to go this route, you must always consider the possibil-ity. Save all sales brochures. Make notes of everything prom-ised, by whom and when. Having sales personnel put their sig-natures beside their recorded promises may cause backpedal-ing that should trigger “Caution, run the other way” warnings.Hopefully, these brochures and notes will become nothing morethan sentimental keepsakes. Keep them anyway. They are thebest evidence. For instance, one of my brochures had a photo ofthe firm’s chairman with his printed message stating: “Leading-edge design. Unsurpassed quality. New technology. Customersatisfaction.” Unfortunately, this wasn’t my experience.

It seemed to me that someone in government should care,namely the Coast Guard since each new boat carries U.S. CoastGuard (USCG) certification identifying load limits and compli-ance to legal standards. 1 The Coast Guard office of BoatingSafety web site (www.uscgboating.org/) has fact sheets, includ-ing a form for “Boat Owner Reports of Safety Defects.” It states:“recreational boats that contain a defect, which creates a sub-stantial risk of personal injury to the public are subject to a recallby the manufacturer.” Unfortunately, for consumers and per-haps the USCG, “substantial risk” is a steep legal threshold.

2 The applicable law is The Federal Boat Safety Act of 1971that “encourages voluntary cooperation and compliance by man-

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ufacturers.” I spoke with an officer at the Coast Guard Flotationsection in Washington (Tel: 202/267-0986), the unit thatenforces those standards. I was told how USCG oversight of aboat manufacture is based on an interpretation that the Act’s“intent of Congress to write minimal regulations that are sup-ported by actual accident data.” When the law was passed, theUSCG reviewed all the actual accident data on file. Most of theaccident reports at the time involved inboard-powered boatsand improperly stored fuel, fuel fume buildup and the acciden-tal ignition of those trapped fumes due to a failure to ventilate.Therefore rules were enacted mandating requirements con-cerning closed fuel storage and pre-ignition venting of inboards.Few regulations concern outboard-propelled boats.

3 I was also informed that it’s the manufacturers who spec-ify the load capacity of hulls, the USCG verifies those limits bytank testing a hull to insure any outboard-powered boat lessthan 20' (6m) floats level when swamped. 4 I filed a USCGsafety defect complaint electronically via their website, stating thatmy boat doesn’t float. There has been no response nor apparentlyany follow up by the USCG. 5 I expended many hours com-posing complaint letters to Offices of Consumer Affairs in bothFlorida (where I bought the boat) and North Carolina (where itwas built), alerting of false advertising claims and failure to com-ply with warranty laws. Both offices just sent the manufacturera copy of my letter, await the response, then send me a formletter indicating “there is a factual dispute” and that the officesare “prohibited by law from acting as a consumer's private attor-ney.” North Carolina office said it needed a court order to provethe dealer or builder “engaged in a pattern of unfair or decep-tive acts,” suggesting I file a small claims action.

As for the trailer, I was unable to identify a single govern-mental regulation or organization concerned about whether aboat trailer sold in a package by a boat manufacturer can carryits load safely. 6 The U.S. National Highway TransportationSafety Council and similar organizations address safety con-cerns about automobiles, big trucks and buses.

In short, no governmental entity was concerned that the boatwas unsafe much less wanted to look at any matter. The fac-tory wasn’t interested in honoring its legal responsibilities; a cer-tified letter to the builder demanding warranty action remainsunanswered. Absent of any “Lemon Laws” to coerce manufac-turers into believing “consensual arbitration” is a good thing,advertisements of warranty are just advertisements. I did man-aged to fix the bilge leak, caused by automatic bailers mountedon the transom but located at or below the waterline prevent-ing the flapper valves from closing, so the boat floats.

Fortunately, a dealer took my “lemon” in on trade and I nowhave a new boat, a new set of problems and still no warrantyor maintenance manuals. And yes, I’m compiling an owner’s

book as DIY suggested. [Ed: How to create an owner’s manu-al for your boat appears in DIY 2001-#4 issue.]

Editorial Notes:1 The USCG doesn’t certify recreational boats. The law pro-

vides that the boatbuilder self-certifies that the boat is built toUSCG standards.

2 It’s very important to understand the rather narrow defini-tion of a manufacturer’s “defect” in the context of the law. Defectsare normally defined as those problems that arise from non-compliance with the law, e.g., failure to certify boat capacitycorrectly would be considered a “defect” under the law. A boatthat leaked at the hull/deck joint might certainly be considereddefective in general terms but would not be specifically consid-ered so under the existing law. The courts usually decide of theimpact of those defects.

3 Accident reporting at the time of the inception of the law ledto mandating requirements is much broader than representedby the writer. They include requirements that affect both inboardand outboard powered boats and address issues of capacity,safe loading, safe powering, flotation and start-in-gear as wellas those related to fuel and electrical systems. Reporting todaystill reflects what has always been the most common types ofboating accidents and those are capsizes and falls overboard,many of which were totally preventable if the victims had wornPFDs.4 The USCG does not test all boats. The testing program isselective and very limited. Boat manufacturers may request thattheir product be tested.

5 The “defect” likely does not fall within the definition of “defect”as defined under the law. Many such “defects” are reported andrecorded but are not acted upon because they are not withinthe scope of the law’s definition.

6 NMMA does certify trailers to this effect.The Magnuson-Moss Warranty Act can be located online at

many University Law Schools or the Government Printing Officesite: www.access.gpo.gov/uscode/uscmain.html. Various statelaws may be more stringent. Don’t hesitate to ask your localconsumer advocate office for help. BoatU.S. keeps a ConsumerProtection Bureau database of consumer complaints on its web-site (www.boatus.com/consumer). Information can only beaccessed by telephone and available only to BoatUS members.

For product info go to www.diy-boat.com

DIY reader Al Perkins has taken on the restoration of an“abused” 34' (10.3m) Chris-Craft Constellation, hull 0070,built in Holland, Michigan in 1963. The cabin has beenchanged to a daysailor configuration and the dining table andsofa area replaced with curved seating on both sides. He isinterested in contacting anyone with a similar boat. You canemail Al at [email protected].

Reader Brian Hall is selling a 1983 33hp Westerbeke 33 with2,500 hours on it and a Hurth 150 V-drive, 3:1 ratio trans-mission. Engine has a closed-cooling system and includes thewiring harness and instrument panel. Engine requires a rebuildbased on compression tests. He's asking US$2200 for thepackage. Contact Brian at [email protected].

WANTED

http://www.access.gpo.gov/uscode/uscmain.html

http://www.boatus.com/consumer


Easy Rope-to-Chain Splice Follow these 10 steps to splice three-strand ropeto chain to make an anchor rode that will passthrough a windlass.

All rope-to-chain windlasses require that the anchorline bedirectly spliced to the chain, eliminating the shackle and thim-ble. This splice is very strong but over time it can chafe wherethe line wraps over the chain. Some experts recommend replac-ing this splice every two years; others suggest every 50 usages.Be sure to add periodic inspection of this splice to your main-tenance log and replace as needed.

Three-strandmedium lay (notfirm, not soft)nylon rope isspliced to chainwith a taperedback splice. Tosplice up to 5/8"(16mm) line,

you'll need a hollow 5/8" (16mm) fid, scissors, tape and whip-ping twine. Mike Paulssen, general manager and in-house rig-ger of The Store in Mississauga, Ontario (www.thestorema-sons.com), demonstrates the steps below. It takes a profes-sional rigger about 30 minutes to do this splice, charging aslittle as $25, which makes an affordable do-it-for-me job shouldyou have a rigger nearby.

1 Measure 12" (30.4cm) from the bitter end of the line. Atthis point, tie with whipping twine and knot securely. Tape eachend to prevent unraveling. Unlay the strands up to the twine,being careful to maintain the natural twist of the line. Arrangethe strands as shown below. You might want to label eachstrand, one, two and three so that strand two is in the middle.

2 Pull the middle strand (two) though the last link of chain.Pass the two outside strands (one and three) through the samelink but from the opposite side so they straddle the middlestrand. Keep the twist of the line as natural as possible. Pullequally on all strands until the knot (twine) is snug against thechain link but not so tight it bunches the fibers or prevents thechain from moving freely. (Continues on page 62)

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1

2 12"

http://www.thestoremasons.com

http://www.thestoremasons.com


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By Patricia Kearns

We think of steel as strong, very strong,and we think of stainless steel as evenmore robust with a sparkling finish tocomplement its resistance to corrosionand rust but all that’s shiny is not alwaysthe stainless steel you think it is. Whenit comes to the nuts and bolts of stain-less steels used in marine fasteners(screws, nuts, bolts, washers), there arevariations on the theme and there aresome absolutes for marine applications.Here’s the drill (pun intended). Bolts,nuts, washers, screws, hinges, virtuallyany hardware that can be fastened to aboat or its components is available in sev-eral metal compositions, known as alloys.

Alloy steel is defined as steel with mod-ified properties made by combining ironwith one or more elements in addition tocarbon. Alloys change the properties ofthe steel making it, for example, harder,more formable or more corrosion resist-ant, depending on the combination andamounts of alloys used. Stainless steels(alloys) encompass a very broad groupof metals. “Stainless steel” is a commonterm for describing steel alloys that con-sist of 10.5% or more chromium (Cr) andmore than 50% iron (Fe). Although it'scalled “stainless,” a better term for it is“highly stain resistant.” The chromium

gives the steel its “stainless” properties,essentially corrosion resistance. On thesurface of the metal, a very thin chromi-um-rich oxide layer, which is inert, isformed and prevents the steel from rust-ing. In general, the higher the proportionof chromium, the stronger the corrosionresistance of the steel. In addition tochromium, other metals are added to givethe steel particular properties such asstrength and malleability.

Stainless-steel fasteners are widely usedin modern boatbuilding and repair becausethey provide strength and affordable cor-rosion resistance but only a few grades ofstainless steel are suitable for boat fas-teners. The 300 series stainless steels arethe most popular. Among them are the18-8 grades that contain very little car-bon, about 18% chromium and 8% nick-el, which give them good corrosion resist-ance. 316 series stainless contains molyb-denum, which significantly increases cor-rosion resistance, strength and of course,cost. There are also “super” stainless steelalloys with significant additions of chromi-um, nickel, molybdenum or copper thatshould be used where requirements forextra corrosion protection, strength or heatresistance are paramount. Other alloytypes, namely 410, 302, 304 (18-8) and

305 stainless, generally provide excellentcorrosion protection in most situations.However, in direct saltwater or other highchloride atmospheres these alloys maypit and discolor. This may cause color tobleed through finishes and lead to streak-ing in the wood surrounding a nail orscrew head.

What distinguishes Type 316 fromType 304 (18-8) is the addition of molyb-denum up to a maximum of 3%.Molybdenum increases the corrosionresistance of this chromium-nickel alloy.As such, molybdenum is one of the sin-gle most useful alloying additives in thefight against corrosion. Type 316 is themain stainless used in the marine envi-ronment, with the exception of fasteners.Where strength and wear resistance areneeded then Type 304 (18-8) is typical-ly used. Type 316 is recommended insaltwater and other highly corrosive expo-sures to prevent fastener pitting and/orhead discoloration and possible bleedingthrough finishes.

Use stainless-steel fasteners cautious-ly below the waterline for they cannotsurvive in an anaerobic (starved of freeoxygen) environment. Because oxygen isnecessary for the reaction, immersion inwater for a prolonged time prevents oxy-gen contact and promotes corrosion. Ifthe screw is immersed in “still water”with no oxygen, the chromium oxide cor-rosion-resistant film cannot form. Withoutthis film, fasteners soon suffer from gal-vanic corrosion and eventual failure.

Not all stainless steel is equal and youdefinitely get what you pay for. You justneed to be sure you know what you need,why you need it and what you’re getting.

ScuttlebuttScuttlebuttAll that Shines is Not Always

Stainless When selecting stainless steel fasteners, knowing which alloy toselect for use above and below the waterline can save somemaintenance headaches.

What’s with “stainless” steel fasteners that rust and leave a dark amber telltale stain?

Stainless-steel fasteners, when used below thewaterline, can deteriorate from galvanic corro-sion from lack of oxygen. In this case, the corro-sion likely developed due to a combination offactors of immersion and the use of a mini-mum quality stainless steel.

Marine Equipment InstallationsHere’s how to choose, install and operate equip-ment for your boat includ-ing: air conditioning and heating systems, audio systems, bow thrusters, davits, lightning protec-tion, propane systems,

refrigeration, windlasses and more.

Fiberglass Boat RepairHow to survey, repair and prevent cosmetic and structural damage in fiberglass hulls, decks and transoms. Includes the step-by-step repair

of minor cracks and gouges, large holes, water-soaked decks, delaminated hulls and proper installation of hardware.

Nautical NecessitiesFrom cleaning to fuel filter-ing to waterproofing charts, you’ll find ideas and inspi-ration in this compilation of tips to do-it-yourself boat maintenance, repair and

troubleshooting. Divided into 20 categories to make look up easy.

Better Boats More than 200 do-it-yourself projects. Practical solutions to deck and cockpit refitting, inte-rior renovations, rigging upgrades, space-saving

equipment storage, safety add-ons and other nifty items to customize your boat.

Sailboat RiggingA practical guide to deck layouts, equipment repairs, performance upgrades, rig tuning, sail controls and steering systems.

Building With Starboard22 Projects and Fabrication Techniques: The ideal choice for replacing wood compo-nents onboard – won’t delaminate, rot or splinter and requires no paint.

Plumbing 101A boat owner’s guide to the inspection, mainte-nance, repair, trouble-shooting and upgrading of onboard plumbing systems.

DIY MechanicGasoline and diesel engine service. How to maintain, troubleshoot and repair outboard engines, stern-drives and diesel inboards.

AC/DC Electrical SystemsA guide to expanding, upgrading, surveying and troublshooting your boat’s AC and DC electrical system. All articles follow ABYC Standards.

Painting & RefinishingThe complete guide to painting and refinishing hulls, topsides and decks with marine coatings.

Launch & Haulout How to prepare your boat for spring launch and win-ter storage. Includes lay-up checklists, maintenance and lubrication guides, engine servicing, haulout guidelines, easy-to-build storage covers and more.

Technical CD-ROM Library for Boat Owners

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Powerboat RiggingFrom gauges to propellers to steer-ing systems, here’s everything you need to know to maintain and repair your boat and trailer, improve boat handling and perfor-

mance, and find solutions to common servicing problems.

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10

Radar Arch Patch-upQ: Do you have a reference that wouldkeep me from making any major errorswhile patching screw holes and repaint-ing an aluminum radar arch that'sinstalled on my boat?Leo Orenstein, “Brer Boat,” Hertford, North Carolina

A: First fill the holes with SeaRepairAluminox (or QuikAluminum), an epoxy-based putty with aluminum fillers. It’sstrong enough to repair engine parts andis a permanent fix for sealing holes. Itcures steel hard, is solvent-free so it does-n't shrink much and is sandable andpaintable. To apply, solvent wipe therepair surface to remove all contaminants.Lightly sand the surface to ensure a goodbond. Follow the prep instructions for thismaterial on the label (cut off a piece,knead it, etc.). Apply and then wait a fewminutes and slice off excess with a sharputility knife dipped in water. Before it fullycures, about five to seven minutes, wetsand with 320-grit paper. Check forimperfections, reapply, if needed, andsand again. Degrease the repair with sol-vent then apply a primer followed by sev-eral coats of color-matched high-glossautomotive spray paint. We did this sixyears ago to fill holes after removing ahydrofoil on an outboard anti-cavitationplate and the plate still looks like new. — Jan Mundy

Cure for Rusting Metal Water TanksQ: We have steel tanks on our trawler.During winterization, I discovered surfacerust on the interior of tanks. Is there aDIY solution for this condition?Jack Wohlgamuth,”Hoist,” Cleveland, Ohio

A: Assuming your water tanks are stain-less steel and your rust problems are therelatively minor bleeding of iron oxidesthat often occur on stainless (especiallyat welds), I suspected the appropriatecure would be some kind of acid cleaner.The dilemma is determining which oneis safe for a potable water tank? For helpI consulted with Abe Kelly of CaptainPhab Marine (www.captphab.com). Hespent many years as a professionalchemist working in the field of water treat-ment prior to bringing out his own line ofproducts. Abe recommends flushing thetank with a 3% to 5% solution of food-grade phosphoric acid available from sup-pliers of cleaning products to the foodindustry. This is used in the dairy indus-try as a rust removing cleaner and flush-ing agent for milk pipes and tankage. Italso has the advantage of reacting withsteel to form an inert surface layer of cal-cium phosphate. This pickles or passi-vates the steel making it more rust resist-ant. Albeit phosphoric acid is non-toxic(it's in Coca Cola), it's a good idea to rinsethe tank with freshwater afterwards. Ifyou discover that phosphoric acid is onlyavailable by the car load, use oxalic acidas an alternative. This is another organicacid used as a rust remover in a varietyof cleaning products, including Capt.Phab Algae & Rust Stain Remover, DavisFSR, StarBrite Rust Remover and others.Oxalic acid does not passivate the steel,however. You likely won't find food-gradepurity and therefore extra flushing is rec-ommended to remove any residual clean-er from the tank. — Nick Bailey.

Steering Off-Course Q: I had the dual rudders and packingsreplaced on my 1975 Chris Craft. Afterdoing this, the cable steering feels veryloose and the boat won't stay on coursewithout holding the steering wheel tight-ly. The wheel turns to starboard, whichresults in a high speed U-turn if thehelmsman isn't careful. The starboardrudder is mounted straight back from cen-terline and slightly outside the propshaft;the port rudder is slightly outward of cen-terline almost directly aft of the propshaft.Some people I've spoken to suggest thatthe rudders may be misaligned or incor-rectly positioned. Paul Seifert, “Lil Rivet,” Cape Haze, Florida

A: You don't want the wheel moving onits own but, without conducting an on-water boat test, it's difficult to ascertainthe problem. Rudders are usually installedsymmetrically and offset from the shaft.Additionally, the balanced spade ruddercould be capsized by prop wash. Is thereany vibration? Rudder vibration thatincreases with engine rpm indicates a rud-der that is too close to the propeller. It'san interesting problem and for assistanceI contacted Mark Ellis, designer of theFreedom Legacy and Bruckmann motoryachts and Nonsuch and Niagara sail-boats. Here’s what he thinks. “Rud-ders ina twin installation are mounted with aspecified toe-in. Changing the alignmentrequires disassembling the drawlink. Ifthis was done, then your rudders mightneed realigning. It's more likely the originalpacking and stuffing boxes were over tight-ened, which put a brake on the steeringsystem. This would be evident if therewas a load or obvious drag previously onthe wheel with the boat at rest (docked)and now the wheel moves freely. Servicingthe stuffing box and not repacking it astight eliminated the brake, causing rud-ders to move freely. A well-engineered rud-der steering system greatly affects the boattracking, as you've discovered. Hull designplays a major role in a boat that trackswell. See if you can contact owners ofsimilar boats to determine if there is aninherent steering problem. A boat willwander off-course with frequent correc-tions to the wheel to hold the headingwhen the longitudinal center of gravity(LCG) is too far forward relative to the hull

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design. In this case, you may need to shift the LCG aft or increasethe lift of the hull at the bow. In a twin-screw boat, the ruddersare installed with different angles.” According to an article inProfessional Boatbuilder (February/March 1997) written bynaval architect Donald Blount on twin-screw boats with out-board turning props, the optimum rudder angle for straight run-ning is with the leading edge near the hull centerline at or aboutan angle of 1° to 3°. If indeed the rudders are not symmetrical-ly located vis-a-vis the propeller shaft, they will need to be adjust-ed. Blount also states that the preferred tiller-arm toe-in/toe-outangle is relative to the length of the tiller arm and the tie rod.To tune the rudders, run a straight course using an adjustablelength rudder tie rod. Fit a turnbuckle to the tie rod or mountend fittings that allow adjusting of the rudder angle offset. Setthe throttles to cruise (or WOT) and measure the speed for eachrudder offset angle, noting any observations regarding the forceneeded to turn the helm and your boat's response in turns.Changing the rudder angles may increase speed, lower steer-ing forces and change the boat's running trim. — Jan Mundy

Specs for Trailer RefitQ: I bought a used Trailrite sailboat trailer for my fin-keel Ranger26 sailboat. It was originally built for a wing keel Catalina 270.How do I determine where to place the support pads, the bestnumber of supports and where do I set the keel in relationshipto the dual axles? Michael Wiseman, “Witt's End,” San Diego, California

A: According to the Marine Cradle Shop, (Tel: 905/294-3507)builders of custom trailers and cradles, you have a few consid-erations as the trailer wasn't built for your boat. If there is a draftdifference between the two boats, you may need to cut downthe steel uprights and install new pods for the adjustable pads. Oncustom-made trailers the upright supports and cross-bars arepositioned so they always lay against an interior bulkhead. Ifpads don't catch a bulkhead, should the boat hit a pothole whentrailering, the pressure of the boat bouncing against the pad canpunch a hole through the hull. You might want to consider replac-ing pads with athwartship bunks. A six post trailer would have twopads and two bunks; a four post requires just two bunks. Thisis a better configuration for a hull when retrofitting a used trail-er. Bunks are made of 2x6 pressure treated wood. To providesufficient tongue weight, position the center of the two axles, 8"(20cm) behind the center of the keel. If using pads, these areplaced so they support the boat in column and won't topple over.They are not meant to support any weight. The weight of theboat should be supported at the keel, the same as for a boat thatis blocked ashore. Therefore, the pads would be placed on thetopsides at the turn of the bilge but not underneath so the boatsits on the pads thus supporting the boat's weight. — Jan Mundy


Trailers are tailor-made so upright sup-port pads always layagainst an interiorbulkhead. Athwart-ship bunks (notshown) provide bestsupport when retro-fitting a trailer notbuilt for your boat.

Cooling Alpha One Q: I would like to know how much water a seawater impellerpump puts out on an Alpha One sterndrive? I have an over-heating issue with my boat's port engine. This engine, the lowerunit, exhaust, all hoses and components are new. I removed thehose from the drive inlet to the heat exchanger and there is nowater yet I blew air through the line and it appears clear withno blockage at the drive. Mark Horn, “Scuba Too,” Stockton, California

A: The Mercury V-8 Alpha power package with closed coolingcan have two styles of seawater supply to the heat exchang-er. If water temperature is below 65F to 70F (18C to 21C),there may be a standard issue seawater pump located in thedrive unit. For water temperatures above 70F (21C) there is ahigher volume belt-driven pump mounted to the front of theengine. This pump pushes around 18gal (68L) per minute(gpm/Lpm) at 2,000 rpm; the drive style pump moves around12 gpm (45 Lpm). Both of these pumps should have the rub-ber impeller changed annually. The impellers don't usually wearout in a year but they can dry out and lose volume from lack ofuse. You can purchase a water pump repair kit from your deal-er. Stick with the original engine manufacturer’s (OEM) parts,the extra cost is warranted. During this process, make sure allwater hoses are in good shape and replace any that are cracked,delaminated or weak. I also recommend double hose clampingeach water inlet hose connection. — Steve Auger

Routing New HalyardsQ: I plan to change my genoa halyard from wire to rope with-out removing the mast (the existing sheaves will work). Is therea trick to attaching a string messenger to the new halyard toget it through the block without having to go up the mast? Itried sewing and taping, but the string seems to fray. Dick Cooke, “Victor,” Fairfield, Connecticut

A: You shouldn't needto go up the mast. Tomake a strong messen-ger, purchase twice thelength of the mast plusabout 15' (4.5m) extraof #4 polyester cordsold at marine stores forwhipping. This won'tbreak or fray. Now tieone cord end onto thehalyard using four ormore half hitches thatextend about 6"(15cm) or so onto thebitter end of the hal-yard, leaving about 1"(25mm) betweenhitches, so that whenyou pull the cord it’ssecured by the hitches.Now tightly wrap duct


How to secure a tie-off used whenrouting a messenger line to pullwires. A more secure method, asdescribed in the text, is needed forhalyard messengers.


13

or similar tape, over the entire length ofbound hitches and halyard. The bitter endof the cord is at the end of the 6" (15cm)wrap. When done properly this won’t pullout. — Jan Mundy

Sealing Leaky Tank Bolts Q: I have a slight leak in one of the fiber-glass diesel fuel tanks on my ProutSnowgoose catamaran. Fuel seeps downbetween the tank and the engine. Thetank is mounted externally between thehull and center nacelle and I'm guessingthat the leak is coming from a mountingbolt that goes through the tank and boltsthrough the engine nacelle. I plan to cut ahole in the top of the tank to get to themounting bolt. What is the best way torepair the leak? It has been suggested touse a two-part epoxy paint or epoxy resinand fiberglass and patch the bolt holefrom inside the tank. Elbert B. Hill, “Sundsvalla,” Pensacola,Florida

A: If the leak is at a fastener (as you sus-pect) and the tank is not loose and mov-ing around, it may be possible to simplyremove and reseal the bolt using a sealant

designed for fuelfittings, such asGasoila Hard-Set made byFederal Process(www.federal-process.com) of

Cleveland, Ohio. It’s available throughOMC dealers but a good automotive job-ber should have it. I doubt painting theinside of the tank with an epoxy will domuch to reseal a leaking bolt and it willbe much work to debunk the fuel,degrease, prep-sand and clean the tankinterior then apply the coatings, allthrough an opening cut in the tank. If thesealant approach doesn't work, the nextbest solution would be to apply a sub-stantial fiberglass and epoxy resin patchover top of the offending bolt(s). I'm con-cerned though, about your boat's fuel tankmounting. Any mounting bolts passingthrough to the inside of the tank are invi-tations to trouble. — Nick Bailey


Use GasoilaHard-Set to sealall kinds ofthreaded fuelfittings.

Mariner Tilt/TrimTroubleshootingQ: I have a mid-80's powerboat with aMariner 150hp outboard that has per-haps 12 running hours over the past sixyears. While docking I had a steeringissue, so I went under the dash to tight-en a nut and the tilt/trim has not workedsince. The only wiring I can see that con-nects to the trim is the dash gauge. I can'tfind any loose wiring connections andeverything else seems to work fine. Thetilt drive is a one-piece unit composed ofsolenoids, an electric motor, pump andsmall reservoir. It's in a dry area behindthe cockpit, sharing space with the bat-tery box and built-in fuel tank. The driveunit is connected to the hydraulic ram byhoses. Some years ago, the up-trim quitbut the down-trim and trailer functionsworked fine until I went under the dash.Now, when I attempt to activate, the up-trim does nothing and down-trim and trail-er simply cause the unit to click. I'veremoved the unit and would like to bench

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test it. Can I do this without frying something if I don't have awiring diagram? If I just delivered the unit to an industrial smallelectric motor shop, would they be able to fix it or does thisrequire a marine mechanic?David Page, “Sea Jay,” Pelican Point, Alberta

A: If this type of power trim pump is a remote pump mountedinside the boat with a large single ram between the engine tran-som brackets, then the pump rotation for up and down is acti-vated by the solenoids mounted on the pump assembly throughdedicated wires from the pump motor. In order to supply thepump's electrical requirements, battery power is routed directlyto the large terminals on the solenoids via a 10-gauge red wirethrough a 100-amp fuse. To activate the up mode, the up but-ton in the dash or remote control sends a 12-volt signal to the upsolenoid via the blue 16-gauge wire. This energizes the solenoidand allows battery current to flow through the solenoid to the elec-tric motor via the large 10-gauge blue wire that runs from theupper solenoid to the electric motor on the pump. The sameprocess takes place for the down mode except the trigger wireand electric motor wires are colored green. The most commonfailures on these systems involve fuses: 110 amp on the pumpfeed and 20 amp on the switch feed. Most auto electric shopscan repair these units as they are quite similar to units used onsmaller snow plows. — Steve Auger

Repairing Keel DingsQ: I ran aground on some rocks last season and took a chunkof metal out of the cast steel keel on my 1997 Hunter 376.I'm considering filling the void with epoxy and building it up toconform to the original shape. It measures about 1" (25mm)in depth and maybe 2" to 3" (5cm to 7.6cm) in width. Whatwould you recommend as a repair? J. Kenneth Michaelchuck, “Orion,” Milwaukee, Wisconsin

A: Any repair here is a cos-metic issue, so you are cor-rect in planning to do asimple fill and fair repair.First, make sure you cleanoff any corrosion with agrinder or wire brushwheel. Next, apply two orthree coats of a good epoxyprimer like Interlux 2000or Awlgrip 545. (This pro-vides corrosion resistance).To ensure best adhesion,apply a stiff (peanut butterconsistency) epoxy filler assoon as the primerbecomes tack free. Oncethe filler is tack free, butnot yet rock hard, shave itto the approximate propershape with a good paintscraper or bodywork file.To cure properly, most


(top) Example of grounding damageto the keel tip; (bottom) Same dentsshaped, filled and faired.


epoxies require a minimum temperature(of the keel, not just the air) of 50F (10C).During spring in a northern boatyard, thistemperature requirement can be achievedby warming the keel for several hourswith a heat lamp before beginning anyepoxy work and keeping the heat on untilthe epoxy is fully cured to a rock hardconsistency. Finish by sanding smoothwith a foam pad feathering sander or ahand sanding board with 40- to 80-gritpaper. If you are fussy, do a final fill witha mayonnaise consistency filler to elimi-nate porosity and small imperfections.Prior to applying antifouling, finish sandwith 80- to 120- grit paper. No primeris required over epoxy filler. — Nick Bailey

Filling Old Transducer HoleQ: I'm currently restoring a 1978 CheoyLee Offshore 32. I plan to remove theold depthsounder and thru-hull trans-ducer and replace them with a modernsounder where the transducer sits insidethe hull. What would be the best wayto repair the resultant hole? Brian McDowell, “Cristina III,” Vancouver,British Columbia

A: Assuming you prefer to repair thehole instead of using it for a new thru-hull fitting, the correct procedure forrepairing a single skin (uncored) lam-inate is to replace the full thickness ofthe fiberglass skin at and around thehole. It's no good mixing up a batch ofepoxy filler and gooping it over the hole.This kind of laminate-free plug or patchis brittle and will crack and start leak-ing eventually. To prep the hole and theadjacent area for new laminates, firstdegrease with solvent to remove anycontaminants and then use a grinderwith a flexible 36-grit disc to grind backand bevel the outside surface of thehull, starting at the edge of the holeand working outwards. Grind out a cir-cular dish-shaped depression centeredon the hole and tapering at a constantangle outwards to a radius of at least12 times the thickness of the hull lam-inate. This makes room for a recessedscarf joint with an adequate bondingsurface for the new patch laminates.For example, if the hull is 1/2" (12mm)thick the radius of the scarf rampshould be at least 6" (15cm). If the


new glass is only applied to the out-side of the hull, the maximum scarfdepth at the edge of the hole shouldbe almost the full thickness of the hull.Note, however, that if the inside sur-face is easily accessible, the ideal repairtechnique would be to apply a glasspatch to both the inside and outside ofthe hull. If an inside/outside repair isplanned, scarf both the inside and out-side to half the depth of the hole.Although the inside/outside repair haslong been considered the best repairit's not mandatory. Lab tests done byStructural Composites for the US Navy(and presented by Art Wolfe at IBEX2000 trade show) demonstrated thatinside/outside repairs offer only anincremental improvement in tensilestrength over the outside-only repair.Once the prep grinding is finished, vac-uum the dust and clean the groundsurface with an acetone dampened rag.Examine the ground surface and iden-


16

tify the different layers of laminate.Ideally you should try and put the samenumber of new layers of glass back intothe patch. Most hulls are laminatedusing alternating layers of 1oz or 1.5ozmat and 12oz to 24oz woven roving.Alternatively, a few layers of 1808 or1810 Stitchmat (which combines themat and roving into a single cloth)makes a good substitute for the tradi-tional mat and roving lay-up. Use theoutline of the exposed laminate layers

as a template to cut the pieces of newcloth you will use. This should ensurethe new glass pieces fit the repairrecess. Presuming they are stackedfrom the smallest to the largest, eachpiece will be in the best position totransfer its load to the correspondinglayer in the original hull laminate. Ifyou are doing an outside-only repair,cover the hole on the inside with heavytape or secure a piece of cardboard inthere to act as a molding surface.Carefully follow the mixing instructionsand temperature requirements of yourchosen laminating resin. Wear protec-tive gloves, Tyvek coveralls, etc. Pre-wet the exposed surface of the scarfand then wet out each patch piece inturn on a table before applying themto the repair with a roller and plasticsqueegee. Most repairs of this type canbe laminated in one session. If you areworking with epoxy in cold tempera-tures (anything under 59F/15C), it cantake a long time for resin to cure. Inthe meantime (usually as soon as yourback is turned), the patch may fall off.To avoid this, be prepared to come upwith some kind of clamping or secur-ing method to hold the wet patch inplace until the resin cures. This maybe as simple as a cardboard cover heldin place with duct tape or as sophisti-cated as a vacuum bag set-up. Afterthe resin cures, grind off any lumpsprotruding beyond the hull surface,prep-sand the low spots with 40-gritpaper and apply an appropriate under-water filler. Use a large putty knife orbatten that can conform to the hullshape to spread and smooth the putty.When the putty is cured, coarse sandwith a block or longboard and spot fillagain if needed. If perfection is yourgoal, apply a fine filler to smooth outthe sanding marks or apply a high-buildepoxy primer or barrier coating. Sandthis with 150 grit and apply yourantifouling. Any repairs on the insidethat may be conspicuous can be sand-ed a bit and touched up with paint tomatch the rest of the interior surface.— Nick Bailey

Soot's an Air-Starved Diesel Q: A 27 hp 3GM30F Yanmar wasprofessionally installed by a Yanmardealer in my Cal 29 five years ago. At


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that time, we upgraded and installeda new exhaust system with a newmuffler, a new propeller (turning3,550 rpm at full load) and Algae-X.From day one, I have experiencedexcessive soot at cruising rpm. Thedealer is now out of business and thedistributor, Mack Boring, runs theother way. The original fuel tank was-n't replaced until after about 50 hoursof use and fuel and Racor filter areclean. I've since replaced (all at myexpense) the injector pump and allinjectors. Besides the Yanmar dealer,two more Yanmar certified mechan-ics have taken more of my money. I'mnow told to put the engine on a dietof Stanadyne three times the normaldose. Some mechanics suggestrechecking the timing and my latestmechanic (who installed the injectorpump) says the shims are fine and Ishould live with the soot. My boatnever leaves the dock with a fouledbottom, and the tachometer is with-in 100 rpm of true. Any truth to theMarvel Mystery Oil claims of cleaningthe system? Or should I just paint thetransom black and keep a supply ofspare exhaust elbows? Bill Shenko, Jr., “Rampage,” Estero Island, Florida

A: You say that the problem existedfrom day one of the installation. Thistells me that there was somethingmissed on the repower. If the enginedoes not have a good cool supply ofair it will soot. If the engine hasrestriction in the exhaust it will soot.If the valves are too tight it will soot.If the propeller was too large, theengine would not turn the rated rpmand it would soot. These are not like-ly the problems as you said as thetiming, injectors and injection pumpare okay, fuel is fresh and all as it waswhen the engine was new and it soot-ed. The problem is not with theengine, it's the installation. Run theengine full power underway with theengine room hatch opened. See whathappens. Does the exhaust clean up?I like Marvel Mystery Oil, but theStanadyne should do the same. Nomagic required here to solve an instal-lation problem. The most overlookeditem in your very comprehensive list isair! — Bob Smith

Laminate patches replace original structureand are oriented from small to large.


Tech TIPS

HOW MANY COATS?: Protect a paintcan label by wrapping a piece of wax paperor aluminum foil around the bottom of thepaint can and securing it with a rubberband to stop drips from running down theside of the can. When you remove thewrapping, the instructions and coveragespecs will be there for the next time youuse that paint.

CLEANER HANDS: To reduce paintbrush (and hand) cleanup, cover the metalferrule on the handle with masking tapebefore you begin to paint.

RIM SHIELD: Shape a protective cov-ering of aluminum foil around the rim tocatch paint drips and keep the rim cleanso the lid closes tightly.

ROLLER REST: Clip a clothespin to theside of the roller pan keeps the roller fromsliding down into the paint while you pausefor a break.

FREEZER ANTIDOTE: Don’t clean abrush if you’re going to use it again thenext day. Instead, tightly wrap it in plasticwrap, place it in a plastic bag, seal welland store in the freezer overnight.

BREAK WRAP: When taking a briefrest from painting, no longer than an hour,instead of cleaning the brush each time,wrap it in plastic wrap or put it in a plasticbag and lay it in the shade.

DEW POINT: Avoid painting in the earlymorning or evening, even on a dry day, asany moisture on the surface from dew cancause blistering of the coating later.

GO HAIRLESS: Always buy good qual-ity natural bristle brushes, the best youcan afford, because cheap ones may shedhairs.

SPIN CYCLE: A brush spinner effectivelyremoves excess paint and cleaning solu-tions. Get a big bucket and spin the brushinside. After washing, spin the brush dry.

20 Tips to Helpwith your Painting Jobs

TRAY JACKET: Cover a paint traywith aluminum foil or slide the trayinto a plastic shopping bag. Whenyou’re finished painting, let the paintdry and then wrap the mess up in thefoil or the bag and dispose of thewhole package.

STORAGE TIP: To stop a skin formingon any unused paint, always stow thetightly sealed can upside down.

QUICK FIX TOOL: When you need totouch up small areas of chipped paint, usea cotton swab or a sponge. Saves clean-ing a brush.

BRUSH CLEANING 101: To properlyclean a bristle brush, dip it in a can ofbrush cleaning solution, remove andspin it dry. Use a comb (a metal petcomb works great) to remove any crud.Repeat the process in clean solvent, ifneeded. Wash the brush with a littledishwashing detergent and warm waterworking the bristles between your fin-gers, rinse a few times to remove allsoap residue, comb it out again andhang to dry.

BRUSH RESTORER: When you don'tget around to cleaning the brush right awayand it gets hard, hang it overnight in a canof strong solvent, such as Interlux 202Fiberglass Solvent Wash, remove, spin dryand then comb it out to remove any hard-ened crud. Repeat the process in cleansolvent, if needed, and finish cleaning asabove.

BRUSH SUPPORT: Never place abrush in a can of cleaning solution with thebristles resting on the bottom of the can.Instead, use a specialty brush cleaning con-tainer with a lid that grips the brush han-dle or drill a small hanging hole in the han-dle just above the ferrule and insert a wire.

MASK REMOVAL: Wait until a coat-ing is tacky before removing the maskingtape.

RECYCLE CLEANERS: With expen-sive brush cleaning solvents, allow sedi-ment to settle at the bottom of the con-tainer, pour off the clear liquid into a cleancontainer and reuse.

SHAPE RETAINER: To keep naturalbristle brushes in good shape after clean-ing thoroughly, wrap an elastic bandaround the bristles and hang so the bris-tles face down. Remove band when dry.

AIR FRESHENER: To remove odorsfrom a newly painted cabin, cut an onionin half or pour 1/2 cup of vanilla (the kindused for cooking) in a bowl, let sit overnightand the paint smell will disappear.

FOR FUTURE REFERENCE: Beforestoring any leftover paint, mark the levelof the paint and the date on the label sothat you will know how much you haveand how old the paint is.

Do you have a boat-tested tip or technique? Send us a photo (if available) and a description, your name, boat name and homeport and mail to:

DIY TECH TIPS P.O. Box 22473 Alexandria, VA 22304

Or e-mail to: [email protected].

Tech Tips Wanted

Reader tips are not tested by DIY, but we won’t publish anything we feel might harm you or your boat.


18

By Nick Bailey

Given the countless submerged hazardson our waterways, the repair of runninggear is a mainstay for many boat yards.Accidental damage is just one of thethings that can and do go wrong with thetypical inboard engine shaft to propellerassembly. Vibration from wear and tearand lack of maintenance are usually yourfirst clues that attention to these vitalcomponents is required.

Some boats are more prone to vibra-tion than others. “It’s been that way sinceI bought it” is no excuse for ignoring minorshaft vibration. Unfortunately, the exactcause can be hard to identify. Vibration

from engine misalignment, shaftbearing (a.k.a. cutlass bearing), wearor damage due to an unnoticed impactcan all feel the same. Continuing to oper-ate a boat with a constant vibration isasking for trouble. Added stresses accel-erate wear at the shaft bearing and cancause failures at the transmission, a veryexpensive end of the shaft. Here trans-mission oil seals and output shaft bear-ings are vulnerable to vibration; particu-larly those caused by shaft coupler mis-alignment (see Figure 1). In the worstcase scenario, a misaligned flange cou-pler works loose from the shaft allowing

the prop shaft tosuddenly exit the boat.

On the way out it fetches up againstthe rudder and jams the steering whilewater pours in through the open shaftlog. Routine maintenance can avertthis sort of disaster. Check and tight-en coupler bolts and grub screws atleast once a year. If vibration seemsto be getting worse, do not delay.Identifying and repairing the prob-lem before there is a catastrophicfailure is priority one. Since vibration is the common

denominator for many different shaftproblems, a professional technician willfollow a step-by-step diagnostic proce-dure to pinpoint the problem. Thisprocess can start at the inboard or out-board end of the shaft, depending onwhether or not the boat is afloat or onthe hard (land).

Step 1: Troubleshooting Afloat

Some yards use a periscope or a diverto check for obvious impact damage tosubmerged hardware but subtle prob-lems are often hard to identify underwa-ter. Always check engine alignment withthe boat afloat. At the same time, a pre-liminary check of the flange coupler alsoreveals any loose fasteners or an obvi-ously sloppy fit. [Ed: Step-by-step detailson aligning engines appear in DIY 2002-#1 issue.] If engine alignment and cou-pler look good, the next step is to haulthe boat to inspect the prop, shaft bear-ing, shaft taper, etc.

P R O S E R I E S

Bad

VibrationsVibration is a sure indicator that something is amisswith your boat's running gear. Here's how to diagnoseproblems and the steps needed to maintain, repair orreplace bearings, propellers, shafts and struts.

Large nut

Propeller “G”

Fairingfiller

Key“F” bearing

Secondarybond

Doubleclamps

Locknut Packing

nut

PackingWire-reinforced

hose

Glass hull skinGlass t ube

Shaft log “D”“E” Stuffing

box

Coupler“B” Engine

and transmission

Nuts and thru-bolts with washers

Bedding compound

Faired andrecessed strut

flange

Hull skin

Flangestrut

Bronzestrut

Rubberbearingmaterial

ShaftShaft

Waterflow

Bronzebearingsleeve

Bearing housing(Part of strut casting)

Cotter

Nut arrangementas per SAE J755, J756

Small nut

Coupler “C” Shaft “A”

FIGURE 1

Major running gear components are the prop shaft (a) with a flange coupler (b) that con-nects to the engine and transmission coupler (c). Shaft passes out of the hull via the shaftlog (d) or stern tube and the opening is sealed by a traditional packing gland, also known asa stuffing box (e) or a dripless shaft seal. One or more bearing (f) supports the shaft and apropeller (g) provides motive force.

Shaft bearings, also known as cutlass bear-ings, are water lubricated and designed forunderwater use only.

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Step 2: Troubleshooting AshoreFirst on the list is the propeller. Any hint of impact damage can

be considered a smoking gun, likely indicating a bent shaft. Aprop that has struck a deadhead or other soft object may notshow any obvious damage but it may have distorted the pitchor blade geometry, which can affect balance. Sometimes, aslightly bent blade is visible by attaching a prop pointer to thestrut or hull (Figure 2). Set the pointer to just touch the tip ofone blade and rotate the prop by hand. As each blade passesthe pointer any minute bend is clearly obvious. Check foldingprops for excessive play at the blade hinges. Balance is a mov-ing target on some folding props and some folding props tendto vibrate even when they are in perfect condition and well bal-anced. If in doubt, check for bearing play first (as outlinedbelow) and if it checks out, pull the prop and check the shaftat the taper with a dial indicator. To remove a prop, extractthe cotter pin and lock nuts then pop the prop loose with awheel puller (not a hammer!) Most yards send the prop out toa specialty shop for inspection and repair as required.

Next, check theshaft bearing for wear.Firmly grasp the propand shake vigorouslyfrom side to side.Shaft bearings aredesigned for a snug fit.ABYC standard P-6appendix, Table V, rec-ommends a clearanceof only .003" for shaftsbetween .75" and1.25"…), so any playdetectable by handindicates a worn bear-

ing requiring replacement in the near future. If the technicianactually feels a distinct “bonka-bonka” as the shaft bouncesbetween the bearing sides, bearing wear is severe enough tobe an obvious source of vibration and immediate replacementis unavoidable. Not all bearings die naturally, many are mur-dered. If the bearing is badly worn, it’s important to isolate and


Wood batten

Tape

Protruding screw

Pencil mark

FIGURE 2

A prop pointer can help indicate aslightly bent prop.

Most props come off easily with apuller.

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repair factors causing premature wear(see “Factors Affecting Bearing Longevity”on page 22).

When the prop and bearing checkout okay, vibration (alone or in combi-nation) involves invisible damage to theprop, the shaft or a problem inboard atthe forward end flange coupler. Toinspect the most vulnerable part of theshaft, the taper, remove the prop. A dialindicator is then used to check the shaftfor straightness. Measurements aretaken at both ends of the taper and atthe mid-point of any exposed shaftbetween the strut and the shaft log. “Inplace” measurements are not as accu-rate as a bench check, which requiresshaft removal, but should identify anysignificant bends. Acceptable deviationvaries according to the size and lengthof the shaft. For 1" (25mm) diametershafts, .006" is considered the maxi-mum acceptable bend. If the shaft dialswithin spec, it’s presumed that theproblem is inboard and any furtherinvestigation requires prop shaftremoval. Removal of the shaft has theadded advantage of allowing a com-prehensive inspection of all running gearcomponents individually. It’s also thebest way to identify any hidden prob-lems, such as excessive shaft wear atthe packing gland.

Troubleshooting vibration can be frus-trating and time consuming. Some boats,usually sailboats with heavy folding propson long, skinny shafts powered by roughrunning diesels that have always vibrated,such vibration continues regardless of a

straight shaft, good prop balance, per-fect alignment and a new bearing. A com-mon characteristic is a bad harmonic res-onance at a specific engine rpm. In somecases, an otherwise perfect but too skin-ny shaft whips like a skipping rope. If hullclearance is a bit tight at the shaft log,the whipping shaft can bow out farenough to beat against the edge of thehull aperture. This produces a loud drum-ming noise, impossible to duplicate onshore. It’s weird cases like this that makemost yards reluctant to quote a vibrationrepair without a detailed investigationfirst.

Replacing a Shaft Bearing Bearing removal and replacement is well

within the skill of a do-it-yourselfer withthe proper tools. Presuming the prop hasalready been removed with a wheel puller,the next step is to find and remove thesetscrew (or screws) securing the bearingin the strut or stern tube. These are oftenburied under coats of antifouling paint.What comes next is subject to many vari-ations depending on the individual tech-

nician and the characteristics of the par-ticular boat. On rare and wondrous occa-sions where the bearing is loose, it’s pos-sible to easily push out the old bearing andpush in a new one without removing theshaft. If more force is required, a screwjack tool can be improvised using a splitpusher sleeve or a discarded bearing ofthe same bearing size. There are also com-mercially available screw jack toolsdesigned for this job such as Strutpro(www.strutpro.com). In many cases, how-ever, the bearing is firmly seized and theusual method (and best if you also needto check the shaft) is to remove the shaft,slice the old bearing lengthwise in a coupleof places with a hacksaw, bend the piecesinward and remove them.

The new bearing may simply slide intoplace but, if not, use a screw jack to pressthe new bearing into place. Pros don’t rec-ommend the Fred Flintstone technique ofbanging the new bearing into place witha block of wood and a hammer. Reinstallthe setscrew(s) with Loctite but don’t over-tighten them as this can pinch the bear-ing out of shape. If the new bearing seemstoo loose, it’s often necessary to bond thebearing in place with a thickened epoxylike Chockfast. Using epoxy means thebearing will definitely need to be cut outthe next time it’s replaced but better thatthan have it come loose in service.

Shaft Removal: Necessary or Not?

Within the framework of general vibra-tion repair, shaft removal is always desir-able and often mandatory. Unfortunately,it’s not always easy to do. If a shaft isseized or difficult to access and there isno other pressing reason to remove it,other than simple bearing replacement,it may be worth pursuing alternatives.Review the troubleshooting steps above tohelp clarify the decision. Meanwhile,check the clearance under and behindthe boat to determine if there is enoughroom to pull the shaft all the way out. Ifnot, the boat may need jacked up or lift-ed and reblocked. Many boats alsoappear to have rudders squarely in theway but, on most powerboats, it’s pos-sible to squeak the shaft past the rud-ders without too much bending. Somesailboat rudders, however, are insur-mountable and require disconnecting thesteering and removing the rudder beforeremoving the shaft.

PRO SERIES

To check a cutlass bearing, grab the propwith both hands and shake it back andforth. There should be no movementbetween the shaft and the strut bearing.

The ideal way to check a shaft for straight-ness is on a bench with a dial indicator.

After removing the cutlass bearing, don’tdiscard it. Used with an improvised screwjack tool it could be useful as a pushersleeve to press the new bearing into place.

http://www.strutpro.com

Shaft removal begins with unbolting the coupler from thetransmission output flange by removing the setscrews or clamp-ing bolts in the sides of the coupler and pulling back the cou-pler, usually with a wheel puller. If the coupler easily slides offthe shaft it’s much too loose and that gets added to the repairlist. Shafts on large motor yachts are a little different, usuallybeing the double taper type. In this case the coupler is securedto a taper on the inboard end of the shaft with locknuts in amanner similar to the method used to secure the prop on theshaft.

It’s an unfortunate fact that shaft couplers on many boats(saltwater boats in particular) are often corroded and seized tothe shaft. In these circumstances, carefully heat the couplerwith a blowtorch or heat gun to assist removal. In extremecases or a situation where the shaft or coupler is due for replace-ment anyway, the best method is to sever the shaft or cut thecoupler in half lengthwise. The preferred cutting tool for thisjob is usually a high-speed grinder that’s fitted with an abra-sive disc designed for cutting steel. Once the coupler and itskey are off the shaft, loosen the packing gland, remove anyretaining collars or sacrificial anodes and carefully push theshaft back out of the boat. Next stop for the shaft is the work-bench for a detailed checkup.

Strut or Stern Tube Removal: An Alternative Technique If shaft removal is anticipated to be too difficult or expensiveand a bearing removal tool is not available, it’s often practicalto remove a seized bearing by first removing the strut or thestern tube assembly and bringing it back to the shop for fur-

ther work. Allpowerboat andmany sailboatstruts have mount-ing flanges that aresimply thru-boltedto the bottom ofthe boat and rela-tively easy toremove, providedthey are not com-pletely out of reachunder a fuel tank

(continues on page 23)

21

Buried inboard end of strut end eith retainer pin

Mound of chopped fibers and resin

Hull skin

FIGURE 3

Cross-section of a glassed-in strut. A strut installed as shown is dif-ficult to remove or repair if it leaks.

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PRO SERIES

Propeller shaft bearings manufacturedby BF Goodrich, Duramax, Morse,Palmer, Thordon and others aredesigned for underwater use only. Mostare made with a rubber bearing mate-rial bonded inside a bronze or com-posite sleeve but some makes are100% composite material. In all cases,the inner bearing surface is grooved orfluted (see photo on page 18) to allowwater to flow through the bearing as acoolant and lubricant. Without this flow,the rubber overheats and wears outquickly, sometimes in as little as 10hours of operation. Rubber bearingsnormally last a minimum of 100 oper-ating hours but many shaft bearingsnever reach this due to original instal-lation problems. It’s important to deter-mine if a worn bearing is just a symp-tom of a larger problem such as restrict-ed cooling water supply, incorrect prop

shaft length, strut misalignment orozone.

Single engine displacement motor-boats and full-keel sailboats usuallyincorporate the bearing into a stern tubeassembly where the shaft exits the hull.This configuration requires some pro-vision to introduce water into the sterntube assembly to cool the bearing.Many stern bearing assemblies haveside scoops to supply water to the bear-ing. If these are fouled or blocked, bear-ing wear accelerates. Twin engine orplaning powerboats and fin-keel sail-boats have the bearing in a separatesupport strut, often described as a “P”or “V” strut, depending on how the strutis configured (single strut mounting ortwo that form a “V.” This arrangement

allows water to flow naturally throughthe bearing provided it’s not blocked bya shaft sacrificial anode mounted tooclose to the strut.

If the prop shaft extends too far pastthe bearing, it’s guaranteed to vibrateand quickly beat up the bearing. Thisis most often seen in a repowered boatwhere the new engine requires a larg-er diameter prop that is too big to fitbehind the strut. Ideally, the front faceof the prop hub should be fitted nomore than one prop shaft diameterbehind the bearing for best support aswell as least wear and vibration. Inthese cases, the strut should havebeen relocated further aft during therepower or a transmission fitted withless reduction.

Sometimes, when a boat builderinstalls running gear components, it’sdifficult to achieve perfect alignmentof the three shaft location elements:the transmission output flange(adjustable within limits), the shaft log(not adjustable but has a narrow tol-erance) and the strut assembly (notadjustable without shimming andremounting). Many boats have strutsthat don’t line up with the shaft log letalone the transmission. Boat buildersget away with this because the rub-ber in the strut bearing is compliantenough to allow the shaft to bejammed at an angle through the bear-

This small opening at the side of a sterntube bearing is an inlet for cooling water. Itshould never be blocked with caulking orantifouling.

Stern tube configuration with fluted cutlassbearing.

This shaft is about 1" (25mm) longer thanideal and will contribute to premature bear-ing wear.

Bearing worn away

Bearing worn awayon opposite side

FIGURE 4

A misaligned strut must be removed, shimmed for correct alignment and reinstalled.

Factors Affecting Bearing Longevity

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(continued from page 21)that was installed before the deck wasmated to the hull. Some sailboat strutsare not bolted but are bonded in place(Figure 3) with fiberglass and are bestleft undisturbed.

Before removing the strut, securelyblock the shaft to avoid inducing a bend.Now remove the nuts securing the struton the inside and gently knock out thebolts. The strut flange may require pryingaway from its bedding compound (or fair-ing filler) and, once free, slide it off theshaft. On the workbench, use a hydraulicpress or screw jack to remove the old bear-ing and install the new one. To reinstallthe strut, slide it over the shaft and mountit with lots of polyurethane bedding com-pound, e.g. 3M 5200, around the fas-tener holes in the original location. Wherethis location is incorrect (see “FactorsAffecting Bearing Longevity” on oppositepage), the strut is carefully realigned tothe shaft’s natural position and chockedwith a thick mixture of epoxy and choppedglass fibers. Redrill the mounting holes, if

necessary, and complete the bedding andfastening.

About the author: Nick Bailey is DIYMagazine’s repair specialist and has spent26 years in the boat repair business. He isthe service manager of Bristol Marine inMississauga, Ontario.

PRO SERIES

Once a strut has been removed and is onthe work bench, a variety of techniques canbe used to remove and reinstall the bearing,such as this improvised screw jack forpressing bearings.

Additional Reading: “Drive Train Tune-up”in DIY 2002-#1 issue features step-by-step bearing replacement, tips for match-ing couplings and checking shafts andtechniques for proper engine-to-propellershaft alignment.

ing. This sort of installation consumesbearings fast. The problem is easy toidentify by inspecting to see if the shaftis running true in the center of thebearing or whether it’s offset in one direction at the front of the strut andthe other direction at the back. Thisproblem can be solved but not with-

out removing and remounting thestruts on solid fiberglass compensat-ing shims.

Rubber components, including shaftbearings, deteriorate over the yearswithout even seeing much service.Exposure to air pollution (primarilyground level ozone) during extendedhaul out periods (especially in theindustrial Great Lakes and Northeastregions) causes the rubber in shaftbearings to harden and crack. Whenused in this condition, they tend tocrumble and fail prematurely. A care-ful examination of the exposed end ofthe rubber will reveal any cracks.

The rubber in this bearing has hardenedand cracked throughout. Soon chunks willbreak off. Best to replace now.

This strut is not glassed in yet is very simi-lar to the one shown in Figure 3. Therecessed flange has been filled over andfaired smooth and hairline cracks trace theoutline of the flange. The thru-bolts areburied just under the filler.


24

By John Payne

Charging technology continues to evolveand the latest development for boats, incommon with the powering of automo-biles, is the fuel cell. Though NASA hasbeen using fuel cells to power its spacecraft for more than 40 years, the biggestbarrier to more readily available cells hasbeen both the cost and the fuel type andstorage. The new fuels cells are commonlycalled direct methanol fuel cells or DMFCs.The replacement of hydrogen with an alter-native fuel such as methanol has allowedan economically viable fuel cell to be man-ufactured and one that can be used onboats. Such technology was originallyinvented at General Electric, who in theearly 1960s developed a small fuel cellfor a program of the U.S. Navy Bureau ofShips (electronics division). Later, fuel cellswere developed for use by the British RoyalNavy submarine fleet.

The basic fuel cell is an electrochemi-cal energy conversion device also knownas reverse electrolysis. The cell convertsthe chemical energy of a fuel, such ashydrogen, natural gas or hydrogen rich fuelsuch as methanol, and an oxidant suchas air or oxygen into water to produce elec-tricity as a direct electrical output similarto a battery.

In principle, a fuel cell operates some-what like the lead-acid battery, anotherelectrochemical device. The fundamentaldifference between them is that where abattery needs recharging, the fuel cell doesnot discharge or have to be recharged froma charging source. Electrical and heat out-put, similar to having fuel in the diesel-powered generator or wind for the windgenerator or sun for solar panels, willalways continue as long as the fuel and

an oxidizer are available in adequate quan-tities. One similarity between batteries andfuel cells is that they both have a positivelycharged anode and a negatively chargedcathode. They also both have an ion-con-ducting material that is also called an elec-trolyte. There are a variety of fuel cells andeach type utilizes different chemistry. Theclassification of fuel cells is generally basedon the electrolyte material that the fuelcells use. The proton exchange membrane(PEM) fuel cell device has the most com-mon application in powering automobileand boat charging systems.

How’s it Work? Basic construction of a fuel cell com-

prises a fuel electrode (the anode) and anoxidant electrode (the cathode). The anodeand cathode are separated by an ion-con-ducting membrane. Oxygen continuouslypasses over one electrode and hydrogencontinuously passes over the other elec-trode. This generates electricity, water andheat. What occurs in fuel cells is that theychemically combine the molecules of thefuel, such as methanol, and the oxidizerwithout any combustion or burning. Assuch, they are pollution-free — no toxic orhigh temperature exhaust emission. Thebyproduct of a fuel cell is a very small quan-tity of carbon dioxide, some pure water anda little heat. The carbon dioxide is aroundthe same as a person’s breath, so somebasic ventilation is required.

The anode is the negative part of the fuelcell. The function of the anode is to con-duct electrons that are released from thehydrogen molecules and these electronscan then be used in an external electricalcircuit. That is the battery part or motor or

other electrical equipment. The anode isconstructed with a series of channels thatis used to aid in the even dispersal of thehydrogen gas across the catalyst surfaceso maximizing efficient reactions.

The cathode is the positive part of thefuel cell. It also has a series of channelsetched into it to ensure reaction efficiencyand to aid in the even distribution of oxy-gen across the surface of the catalyst. Thecathode also conducts the electrons in theexternal circuit from the catalyst, whichthen recombine with the hydrogen ionsand oxygen to release water.

The electrolyte is the PEM. It consists ofa specially treated solid polymer electrolytematerial that resembles kitchen plasticwrap. This membrane conducts the posi-tively charged ions through it and blocksthe passage of electrons. It works at verylow temperatures, about 175F (79.4C).

The catalyst is manufactured from a spe-cial material that triggers and speeds upthe reaction of the oxygen and hydrogen.Typically, it comprises a thin coating ofplatinum powder that is layered onto asubstrate of carbon paper or cloth. Thecatalyst is also rough and very porous. Thisensures that a maximum surface area ofthe platinum material is exposed to thehydrogen or oxygen to ensure maximumreaction takes place. The catalyst is alwaysorientated towards the PEM. For this typeof fuel cell to work, the PEM electrolytemust allow passage of the hydrogen pro-tons but prevent the passage of electronsand other heavier gases.

Fuel Conversion While hydrogen was a major compo-

nent of earlier basic fuel cells, it’s not read-ily available to buy and is inherently dan-gerous. To overcome this, a device calleda reformer is used. This converts hydro-carbon or alcohol fuels (i.e., methanol) intohydrogen and then supplies it to the fuel

E L E C T R I C A L

MaxPower MFC 100 AHD, one of the firstfuel cells packaged for boats, produceselectrical energy efficiently, quietly and with-out combustion.

Generating Power with

Fuel CellsImagine having a clean and quiet source of 12-volt poweravailable 24/7 anywhere you choose to cruise. No noisy engine orgen-set, no relying on solar power, no whirling wind generator.Imagine no longer — fuel cell technology has arrived!

cell. Reformers also generate some heat and produce other gasesin addition to hydrogen and this tends to lower the overall effi-ciency of the fuel cell. Methanol is a liquid fuel that has manysimilar properties to gasoline. Better yet, it’s a farmed fuel, arenewable source, processed from sugar cane. It also is less flam-mable than hydrogen so is ideal for carrying safely on a boat.

Efficiency If the ideal fuel cell is powered using pure hydrogen, it can be up

to 80% efficient, a very high number. Using a reformer to con-vert methanol to hydrogen drops this efficiency to around 30%to 40%. Converting electrical energy into mechanical work usingan electric motor or an inverter, this number falls to around 24%to 32%, still a lot more efficient than solar, wind or generators.The reaction in a single fuel cell produces a fairly low 0.7 volts.However, like a 12-volt battery that consists of six cells, basic fuelcells are built to form a fuel cell stack. To increase power sourceavailability, fuel cells can be connected in parallel, the same asgetting more amp-hour (Ah) capacity with a battery. For exam-ple, two 100 Ah fuel cells wired in parallel equals 200 Ah.

Here and NowMaxPower (www.max-power.com) MFC 100 AHD fuel cell

units now available require a 10 lb (4.4 kg) fuel cartridge thatlasts three days or 72 hours on full power. It produces 340 Ahof 12-volt DC power over a longer period if charging intermittently.The MaxPower unit is made by the Navimo group and utilizesthe Navimo distribution network (Scandvik in the U.S.) to dis-tribute fuel cartridges. Fuel cells are not service or maintenancefree; however, given there are no moving parts, this is significantlyreduced. A fuel cell stack gradually degrades with a slow decreasein performance during its operational life. Stack life typically is a min-imum of 1,500 hours up to or exceeding 5,000 hours. Stackreplacement is relatively simple and fast. Given that a basic fuel cellunit weighs in at just 16 lbs (7 kg), it’s easy to ship replacementsto the nearest service center.

MaxPower units are distributed in the U.S. by Scandvik(800/535-6009; www.scandvik.com), which is also handlingfuel cartridge recharging and fuel cell replacement. Current retailprice for the MFC 100 AHD is US$5,999. Laboratory grademethanol to refill one fuel cartridge is expensive, $40 for 1.3gal


Hot Water

Membrane

HydrogenHydrogen

Anode (-)

Oxygen

Catalyst Cathode (+)

Water

Oxygen

H2 H2O

O

H0

H0

(5L), though sales manager Sabastian Blackman expects prices todrop substantially. Replacement fuel cells are available to pur-chase from Scandvik for US$700.

Selection CriteriaA fuel cell is designed to run constantly over a 24 hour peri-

od. It can be operated in either a standby or in float charge modefor charging batteries; whereas, solar and wind charging systemsdepend on the elements being available for limited periods. Fuelcell costs equate to a very small 2kW diesel gen-set but withoutany of the installation and engineering costs or issues, such asseawater plumbing and exhaust systems.

The big savings are realized because, when a fuel cell oper-ates in continuous float mode, the batteries are always toppedup, constantly held at between 70% to 85% of their full charge.Battery life is greatly increased when the batteries do not haveto go through the discharging and repeated deep cycling thattaxes their performance. This also allows you to install a muchreduced battery bank size. The battery bank ultimately ends updoing float service and supplying system power surges or higherdemands, while the fuel cell supplies the main power. Powertransfer is completely automatic. The MFC 100 AHD, for exam-ple, automatically monitors the battery voltage, switching on andoff as needed. When the engine alternator kicks in, this deviceswitches off.

As technology continues to improve, the fuel cell will becomean integral part of an onboard renewable power source to chargebatteries.

About the author: John Payne, DIY’s electrical consultant, is thecommissioning manager for BP Thunderhorse, the world’s largestsemi-submersible oil platform installed in the Gulf of Mexico.

Fuel cells are a power “generating” device as they draw fuel from anexternal source, such as a hydrogen cylinder, and mixes with oxygen toproduce water and generate electricity for as long as the fuel is supplied.

DIY asked bluewater cruisers and professional videogra-phers Paul and Sheryl Shard for their opinion on the useof fuel cells. Here’s what they had to say.

On our 37' (11.2m) we use 60 to 80 amp-hours (Ah) of elec-tricity per day at anchor (fridge, computer, lights, etc). This isreplaced into the battery by our solar panels which generateroughly 30 Ah per day in the Mediteranean. So we have a short-fall of 30 Ah to 50 Ah per day.

The MaxPower unit produces 340 Ah of power on one fuelcell. Therefore, I can get from seven to 11 days of use from onecell before changing it, assuming the solar supplies the rest. Sobefore leaving for a three-week cruise we might need to pur-chase two to three extra cells from a local fuel cell supplier. Asthese cells weigh 10lb (4.5kg), that’s an extra 30lb (13.6kg)onboard. Finally, after between 1,500 and 5,000 hours of oper-ation we would need to replace the stack. We would need toreturn the unit to have this replaced.

— Paul and Sheryl Shard have logged more than 40,000 nauticalmiles aboard “Two-Step” a Classic 37. They have crossed theAtlantic Ocean three times and have sailed to more than 35 coun-tries including the Caribbean, South America, Europe and theMiddle East. They are currently in the Mediterranean filming anew season of their sailing adventure TV series, “Distant Shores”(www.distantshores.ca).

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By Peter Pisciotta

The skies are crystal clear and the viewof the coastline is gorgeous but an off-shore high-pressure system has beengrinding against a deepening inshorelow-pressure cell for the last two days.The resulting pressure gradient has gen-erated 25-knot winds and whipped upsteep chop off the port bow. The motionis uncomfortable but not extreme sothere’s no thought of retreating. Thediesel drones rhythmically as progressto windward is slowly made. Rhyth-mically it runs, until the rpm drops fora moment.

Engine rpm returns to its pre-set lev-els so quickly that the captain can’t besure they actually dropped at all. Didrough seas dislodge debris in the fueltank? Is it now clogging the fuel filters?A few moments later, all uncertainty isextinguished when engine rpm dipsagain. The scenic coastline will be a lee

shore should the diesel die.Most boats have very simple fuel sys-

tems (Figure 1) that would benefit froma few upgrades. Engine rooms litteredwith valves in tedious, obscured loca-tions where it requires a detective’sinsight to understand how the systemworks and what to do to make changesin the fuel flow directions. Filters maybe impossible to reach or are obsoletemodels without water separation capa-bilities. Fuel lines are often cheap, non-certified deteriorating rubber with hoseclamps slicing through jackets.

Unraveling the mess in an engine roomcan be fairly simple and involves threeeasy do-it-yourself projects. First, installa fuel polishing system that cleans andcirculates fuel on demand (Figure 2).This is especially important to boats likesailboats because diesel has a short shelflife and doesn’t store well (more on that

later). Second, installa dual-element sec-ondary filter on themain engine. Withthe turn of a valvehandle, an operatorcan instantly shift toa clean filter, evenchange-out the dirtyone while the enginecontinues to run.This is especiallyimportant for single-engine boats. Lastly,simplify the systemby centralizing valvesinto a manifold,"valve farm" location(Figure 3).

Know thy EnemyThere are four primary culprits in fuelsystem failure: dirt, water, algae andfuel decay. Dirt is self explanatory butthe other three deserve a closer look.Water destroys injectors very quicklyand, because it’s heavier than diesel,it sinks to the bottom of a tank, pre-cisely where fuel is drawn. Water invari-ably occurs in fuel tanks where smallamounts commonly accumulate fromcondensation. Other culprits includeleaky deck-fill fittings (check gaskets orO-rings regularly) and ill-planned fuelvents that are vulnerable to water intru-sion in rough weather. Also, the origi-nal fuel source may be contaminated,an especially difficult problem in ThirdWorld countries. Most modern fuel fil-ters include water separators but theybecome overwhelmed with more than afew ounces of water. Transparent bowlslet you keep an eye on this process.

An anaerobic strain of algae prospersin the boundary layer of diesel andwater present in almost all tanks. Asalgae decays, the dead cells sink andform sludge in the bottom of the tank.Rough seas agitate the fuel and dis-lodge this goo, which then is drawn intothe fuel supply line where it clogs fil-ters. Biocide additives kill algae andmay temporarily eradicate the problem

D I E S E L

Optimizing

Fuel QualityA well-engineered fuel system involves the onboard cleaning,filtration and transfer of fuel. Improve your boat’s fuel systemand keep your diesel engine humming without skipping a beatwith these simple do-it-yourself upgrades.

Clearly labeled valves.

Best is to have all valves organized in alogical manifold system.

Color Key:

Figure 1: Typical Twin Engine Application

SupplyReturn

CheckValve

Engine

Engine

Fuel Tank Fuel Tank

Generator

1

1

A typical, twin engine installation with two tanks. 1 Cross-over valves closed under normal operation. Starboardengine draws and returns from/to starboard tank. Port enginedraws and returns from/to port tank.

Joe

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28

but you’ll need lots of replacement filtersto get you through the transition peri-od.

As fuel ages, it decays. Tar-like glob-ules of asphaltenes precipitate and sinkto the floor of the tank. Sailors and long-range trawlers are especially vulnera-ble because fuel starts to degrade with-in 90 days and these miserly boats maykeep fuel aboard for months or years.The best solution is to use your boatand consume the fuel. Fuel stabilizersand regular circulation can help, thoughyou’ll need a good supply of filters untilthe globules are resuspended. [Ed: Fordetails on what additives are available,when to use them and test results referto DIY 2001-#3 issue.]

Simple Fuel SystemUpgrades

The further a boat ventures fromhome, whether power or sail, the morerobust the system has to be. For manycruisers venturing into remote areaswhere fuel may be questionable andfuel conditioning supplies non-existent,a robust fuel system is especially impor-tant. The following is a list of “best prac-tices” for initial fuel system design. Notall elements can be retrofitted into anexisting system but it’s a good list toconsider (Figure 4).

Clearly mark and map valves for easyaccess and organize plumbing in a log-ical layout. “Valves should be clearlylabeled with purpose and flow direc-tion,” according to Bob Senter who seesa lot of engine rooms as senior techni-cal trainer with Alaska Diesel, builderof Northern Lights generators andLugger diesels. “A schematic board withcolor coding and icons for all enginesand tanks is very helpful. If possible,mechanically link valves in a way thatprevents them from being mistakenlybeing turned off,” explains Bob. Best isreally a centrally located and well-designed valve farm (manifold). Often,valves are scattered throughout anengine room in inaccessible places.Sometimes, adjunct equipment hasbeen installed (homespun transfer sys-tems for example) and have so manyscattered, unmarked valves. Fuel sup-ply/return manifolds should have spare

outlets so fuel supply lines to futureequipment installations (generator,diesel heater, etc.) can be easily added.If you’re designing and fabricating amanifold system for your boat, makesure you check with ABYC H-33, DieselFuel Systems, for the requirements forfittings. It might be tempting to usecheap, ordinary plumbing fittings butthe plastic ones will probably not com-ply with the fire test requirements ofthe standard. [Ed: Construction detailsfor one example of a plumbing mani-fold appear in DIY 2002#2 issue.]Look at Figure 2 and imagine an actu-al engine room with a valve farm. Itlooks simple on paper but can be veryconfusing in an engine room, especial-

ly with more than two fuel tanks. Install a remotely mounted second-

ary filtration system. Ideally, thereshould be dual filters mounted side-by-side that can be instantly switched soa clean filter can be brought online

quickly and the clogged filter changedwithout disruption to engine operation.If you only have a single fuel filter foryour main engine, you are vulnerable.If your filters clog, you will have tochange filters in a rocking, pitchingboat. A better solution is to install a hotstandby filter. You can make your ownwith two single filter housings and abevy of valves befitting a nuclear reac-tor (and the hope that you know whatvalves to turn when the time comes) orget a purpose-built unit from Racor. TheRacor unit is much more compact andyou just turn a single handle.Convenience comes at a price; this unitstarts at about US$750 plus fittings.

Install calibrated sight tubes. Fuelgauges are notoriously inaccurate and

DIESEL

Dual-mounted water separating filters. Notevacuum gauge.

Having the ability to switch the fuel supplyto a day tank makes troubleshooting pos-sible while the engine continues to run.

Certified fuel hose is marked with SAE,UL, USCG and/or ISO standards’ compli-ance information. Only the SAE and USCGmarked hose is approved for compliancewith ABYC standards. The mandatoryUSCG fuel system requirements do notapply to diesel powered boats. ISO stan-dards’ compliance is mandatory for dieselpowered boats built in the countries whereISO is the law of the land.

Calibrated sight tube made of standardplumbing fittings and Lexan tubing.

other aftermarket monitoring systems require significantinterpretation. Sight tubes are bulletproof. If the boat hastwo tanks, it’s handy to have the ability to transfer fuelbetween tanks and trim the boat. If it has more than twotanks, it’s mandatory to be able to perform this function.

Install a polishing system (Figure 2). The further you ven-ture from home, the higher on your list of fix-it priorities thisshould be. Fuel polishing services are expensive and some-times need repeated service. Fuel polishing is nothing morethan filtering and circulating onboard fuel and is part of afull-feature fuel transfer system (refer to typical schematicsthroughout this article). If you are considering hiring a tech-


29

Color Key:

SupplyReturnTransfer/Polish

Fuel Tank Fuel Tank

Engine

Engine

Generator

Figure 2: Simple Transfer/Polish System

CheckValve

Vacuum Gauge

Fuel Transfer Pump1

1

Simple transfer/polish system works fine but cannot be operatedwhile the engine is running due to contention issues.Nevertheless, this is a great retrofit as long as you do not need totransfer fuel while underway.1 Cross-over valves closed under normal operation. Starboardengine draws and returns from/to starboard tank. Port enginedraws and returns from/to port tank.

Engine

Engine

Generator

Figure 3: Organizing Valves Into Manifolds

Color Key:

SupplyReturnTransfer/Boost/Polish

Fuel Tank Fuel TankBoostPump

SupplyManifold

ReturnManifold

Transfer Pump

Transfer Manifold

1 1

Organizing valves into manifolds on twin engine installation, whilethere is more equipment, is vastly more flexible, intuitive and easilymanaged. When you need to make a fast decision, you have agreater likelihood of getting it right the first time. This configurationalso lets the operator bleed any engine by using the boost pump topressurize the supply manifold.1 Cross-over valve closed under normal operation. Starboard enginedraws and returns from/to starboard tank. Port engine draws andreturns from/to port tank. All connections to fuel tanks have valves,always in “on” position.


30

nician to polish the suspicious fuelonboard the used boat you have justbought, why not have the technicianinstall this system and do it yourself?

A drain-off at the lowest point of thetank is useful to remove water. Useonly certified fuel lines that are wellprotected from chafe.

Install a vacuum gauge on the engineside of a secondary filter (as shown inphoto on page 28). If you have a Racorfilter housing, replace the tee-handle onthe top with a vacuum gauge.Otherwise, tee into the supply linebetween the engine and the filter andinstall a gauge. As the filter clogs, theengine has to pull harder, which createsa vacuum. Once the vacuum starts tocrest 5" hg, you will need to start plan-ning when to change the filter. At 7" hg,its time to change it.

Install a low-flow “boost” pump in thesupply side to simplify bleeding theengine. If your fuel valves are arrangedin manifolds, pressurizing the entire sup-ply manifold lets you bleed any engine(generator, etc). Also, if filters start toclog, the pump pushes fuel through thefilters, extending their range in a pinch.

Add a day tank that holds enough fuelfor five to 24 hours of running at cruis-ing speed. Obviously, this is only prac-tical for slower, long-range cruising boatsthat have modest fuel requirements. Themain tanks act as a reservoir where fuel

is stored until it's filtered and pumpedinto the day tank. If a fuel problemdevelops, the day tank gives severalhours of running time for the operatorto solve the problem.

The final and perhaps easiest do-it-yourself project is to upgrade your skills.Take a diesel education course or hireyour mechanic for a few hours. Talk toyour engine manufacturer and see if itoffers a course. Education is always agreat investment.

Most boaters take their fuel systemfor granted. It’s easy to do and unfortu-nately, many boat builders respond tomarket indifference by only installingbasic fuel systems. Think about thathapless captain in the opening sequenceof this article. What would happen ifthis happened on your boat? Do youhave a vacuum gauge and can you tellif your filters are clogging? If they were,what would you do? With just a few ofthese upgrades, you can avoid this sit-uation altogether and, if you did findyourself in trouble, you would merelyswitch a valve and press a new filter intoservice without the engine missing abeat.

About the author: Peter Pisciotta is aUSCG licensed 100-ton master, pastcommercial captain and current owner ofSeaSkills Personal School of Seamanship(www.SeaSkills.com).

Very few recreational powerboats arecapable of crossing oceans. There isone builder who specifically designs itsboats to do just that. In fact, severalof its boats have circumnavigated theglobe, including a 40' (12m) that, in2001, sprinted around the world injust 170 days. Although a factory spon-sored event, this boat was essentiallya production boat with the same965gal (3,652L) capacity that allNordhavn 40’s carry.

Fuel range was tight on the 2,300nautical mile California to Hawaii legso Pacific Asian Enterprises (PAE), par-ent to Nordhavn and Mason Yachts,developed a clever idea to monitor con-sumption. In addition to fuel flowmeters (i.e., Floscan), a 1gal (3.78L)fuel tank calibrated to the 1/10 gallonwas installed. At least once a day, theactual consumption was measured overtime. The boat arrived with over100gal (378.5L) of fuel in reserve.

Fuel management is critical. Theengineers at PAE developed severalnovel ideas that have been incorporat-ed into modern designs. “Fuel man-agement systems need to be as sim-ple as possible,” according to PAE pres-ident Dan Streech. “Long distance voy-aging can be tiring and stressful so it’seasy to make a mistake. Switching thewrong valves could over-fill a tank anddump hundreds of gallons of fuel over-board. In addition to the environmentalissues, it could easily mean falling shortof the destination,” eplains Dan.

After hundreds of thousands of oceanmiles of research and development,PAE introduced a simplified fuel sys-tem on its Nordhavn 47 that has been

DIESELCase Study: Nordhavn

Color Key:

SupplyReturnTransfer/Boost/Polish

Engine

Generator

Fuel Tank Fuel TankBoostPump

SupplyManifold

ReturnManifold

Transfer Pump

Transfer Manifold

Figure 4: Full Feature Single Engine Fuel System

Single engine fuel system with all valves organized into easily accessible manifolds. Boostpump allows bleeding of the engine or gen-set.

http://www.seaskills.com


31

incorporated into all subsequent mod-els. Two main saddle tanks are out-board of the main engine(1,425gal/5394L total). A third 70gal(265L) supply tank is centered just for-

DIESEL

Fuel polishing systems from Algae-X(www.algae-x.net) combine fuel conditioning,filtration and water separation. Algae-X fuelconditioners installed between the supplytanks and primary filters are said to enhancethe combustion process to improve engineperformance. These units utilize magneticfuel conditioning technology to change fuelcharacteristics that ultimately results inimproved filterability, combustibility and sta-bility. The FPS unit consists of an Algae-Xfuel conditioner to reverse the process of fueldeterioration and buildup of tank sludge andstabilize the fuel; a centrifugal water sepa-ration system removes water; and a fine fil-ter removes solid contaminants.

If you are skeptical of this technology con-sider that units are available from an increas-ing number of boat builders and engine sup-pliers. According to Bill O’Connell of Algae-X, fuel conditioners are standard equipmenton Carolina Classics, Christensen Yachts,Cruisers Yachts, DanMar Power Cats,Nordhavn and Shamrock. Additionally,Detroit Diesel distributors worldwide sellAlgae-X fuel conditioning products and fuelpolishing systems. Other engine suppliersinclude several Caterpillar, Cummins,Westerbeke and Yanmar distributors. — Jan Mundy

Algae-X FPS fuel-polishing system is anaffordable solution to eliminate water,sediments and particulate while recon-ditioning and stabilizing the fuel.

Algae-X utilizes magnetic fuel condition-ing technology to enhance engine reliabil-ity and prevent engine damage.

Color Key: SupplyReturn

Transfer/Boost/PolishDrain at low point on each tank

MainEngine

EmergencyEngine

Supply Tank

Generator

PortFuel Tank

StarboardFuel TankDay

Tank

Figure 5: Nordhavn 47 Improved Fuel System

ReturnManifold

Transfer Manifold

1

Nordhavn 47 improved fuel system incorporates three fuel supply tanks. All connections tofuel tanks have valves, always in “on” position. 1 Emergency or wing engine is a dedicated propulsion unit with shaft and prop.

ward of the engine and sits relativelylow, though well clear of bilge water.This configuration enables several noveldesign elements: the supply tank caneither be gravity fed from the maintanks or filtered through a transfer/pol-ishing system; by using a central supplytank, the main tanks can be drainedcompletely dry without risk of intro-ducing air into the engine feed fuel andno reserve fuel need remain in thetanks; all valves are accessible andclearly marked.

Virtually all Nordhavns comeequipped with a wing engine, a com-plete spare propulsion unit includingshaft and prop that can be used as aback-up should the main engine orshaft fail. To isolate the wing enginefrom potential fuel contamination prob-lems, it draws its fuel from a small daytank that can only be replenished froma filtered source. PAE also limits tankcondensation by routing the return lineto the bottom of the tank so the hotdiesel is cooled by the fuel in the tank,which keeps water from vaporizing andcondensing.

While this robust fuel system addssubstantially to the price of the boat,owners appreciate the well-engineeredsystems. — PP

Joe

Van

Vee

nen

Packaged FuelManagement Systems

Calibrated fuel tank gauge simplifies dailyfuel checks.

http://www.algae-x.net


32

By Sue Canfield

When moist warm air is cooled, it dropsits moisture. Outdoors, this moisture iscalled rain. Inside a boat, the moisturethat collects on hull and cabin surfacesis called condensation or sweat. However,when condensation gets so heavy itbegins to drip (typically above your bunk),you can call it “rain” too.

The solution would appear to be sim-ple. Either you keep the air in your boat’scabin from being moist or you keep themoist cabin air from being cooled. Thedevil is in the details. Just consider howair inside a boat becomes moist (humid).First, there’s ambient humidity outsidethe boat, which can vary from say 30%to 100%. Then there’s the water vaporwe all exhale as a function of respirationand the moisture produced when cook-ing or showering. Unvented (no chim-ney) fuel-burning appliances, such as gal-ley stoves and cabin heaters, put a gal-lon (3.78L) or more of moisture into theair for every gallon (3.78L) of fuel theyburn. Last, but not least, there may bestanding water in the bilge.

Fortunately, humidity belowdecks canbe minimized by ventilation (bringing inless humid air from outside) and by usingelectrical appliances or fuel-burning appli-ances with vented combustion chambers.If shorepower is available, you can evenuse a dehumidifier. (Tip: when you leaveyour boat unattended, it’s best to havethe condensate drain directly overboardvia a dedicated thru-hull or sink drainrather than into the bilge or a showersump, where a pump is needed to getthe water out of the boat.)

One of the best ways to battle humid-ity belowdecks is to keep the bilges dryand I mean completely dry! If your boat’s

bilge pumps don’t discharge all thewater use a bucket and sponge or aShop Vac (wet) to remove what’s leftbehind. After doing this for a few weeks,you will have a much better idea justhow much water is leaking in and bemotivated to track down its source(s).Then you can eliminate the leak(s) byrebedding deck hardware and thru-hulls,recaulking ports and windows or what-ever else may be required. Your rewardwill be a dry, sweet-smelling boat, whichis no small achievement. [Ed: Detailson finding and fixing leaks below thewaterline appear in DIY 2004-#1.]

Ventilation is DivineWhen cabin humidity levels rise, use

passive and active (mechanical or pow-ered) ventilation as needed to bring infresh air and to exhaust stale air.Ventilation is also essential in hotweather to moderate cabin temperaturesand, in cold weather, to circulate heatthroughout the boat. Effective ventila-tion requires at least two openings tothe outside: an intake (add to) and anexhaust (remove). In the absence ofeither, you’ll never get proper airflow.Ideally, the intake should be at one endof the boat (cabin or compartment) andthe exhaust at the other. Generallyspeaking, if a hatch is positioned so theairflow outside the boat is deflecteddownward, it will bring air inside(intake). If positioned to deflect the air-flow outside the boat upward, the hatchwill create a partial vacuum and air willbe sucked from the boat (exhaust).Opening ports, windows and doors func-tion as intakes or exhausts dependingon their location relative to the airflow

outside the boat. Cowl vents, which canbe turned to face in any direction, serveas an intake or exhaust as needed.

My 37' (11.2m) sailboat wasdesigned for offshore use. It has threehatches (including a large butterfly hatchand louvered companionway doors), 11opening ports and four Dorade vents.Consequently, there are many ventila-tion options available. I lived aboardcomfortably, winter and summer, formore than 10 years. In my work as amarine surveyor, however, I’ve seenmany boats that have little or no provi-sion for passive or active ventilation.When hatches, ports, windows anddoors are closed, there is no air move-ment absent air conditioning (or heat-ing) system. High humidity and con-densation — in the absence adequate

U P G R A D E

A Survival Guide To

VentilationGood condensation appears on the outside of cold beverages.Bad condensation leads to soggy potato chips, wet bunks, musty air and with time, mildew, mold and corrosion. That’s why every boat owner should know how to eliminate the “bad” by improving onboard ventilation.

Suggested placement of passive and activevents: (top) Underway, even in foul weather,clamshell vents circulate air through theengine compartment while active intake andexhaust solar vents move air throughout thecabin. (bottom) Passive cowl and solar ventsmove air throughout the entire cabin. Bothlayouts would benefit from opening deckhatches and using interior 12-volt fans. Infair weather, at anchor or in port, hatches,ports and doors can be opened to provideadditional ventilation.

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ventilation — will damage electronicsand cause fabrics to deteriorate, metal tocorrode, paint to peel and wood to rot.Fortunately, there are a number ofoptions for improving a boat’s ventila-tion.

The trick is to use your boat’s hatch-es, ports, windows and vents to provideadequate ventilation in fair weather andfoul. At anchor is easiest because theairflow (wind) is predictably from ahead.In fair weather, the foredeck hatch canbe left open to act as an intake (if hingedon its aft edge) or exhaust (if hinged onits forward edge). An aft door or hatch isthen used for air intake or exhaust asneeded. Opening ports and windows aretypically of greatest use when your boat’stied up in port, where the wind mightcome from any direction. (Remember,when there’s a gasoline-powered engineor generator running onboard or on aboat alongside, exercise special cautionto ensure that deadly carbon monoxidedoesn’t enter your boat.)

Passive Ventilation When underway, forward facing (aft

hinged) hatches may be closed toavoid taking on water. In heavy seasor rain, most, if not all hatches, portsand windows are closed. At thesetimes, passive cowl vents provideintake air and are most effective whenmounted on top of a Dorade box orwater trap. [Ed: Plans to construct aDorade box appeared in DIY 1996-#2issue and are available on the MRT“Boat Refit” CD-ROM.] Typically madeof fiberglass or wood, a Dorade boxcovers a duct into the cabin that’s off-set from the ventilator and the box hasholes so that any water that entersdrains out. The air duct inside the boxshould have a raised lip to keep waterout of the cabin.

Other types of passive vents, suchas mushroom or clamshell, are lesseffective than “baffled” cowls for cabinventilation, but they work well in otherapplications. A mushroom vent, oper-able from inside the boat, can also beused to close off the air duct inside aDorade box, though this restricts theairflow. This avoids the need to go ondeck to remove the cowl and replace it

with a threaded plate when unusuallyheavy seas or weather threaten.Mushroom vents can be installed ver-tically too, on the side of a trunk cabinor over an exhaust fan duct from thegalley or head. I use a low-profilemushroom vent as a deck cap for myboat's cabin heater flue pipe. In heavyweather, it can be closed to keep waterfrom entering the flue.

Non-baffled cowl or clamshell ventsare best used where water intake isunlikely; for example, where the ventopening faces downward or away fromthe expected airflow. Clamshell ventsare often used to cover a cable passthrough, an application where airflownormally isn’t an issue.

Active VentilationThe airflow of cowl or mushroom

vents is limited by the amount of airrushing over them. Powered mushroomvents, which operate day and night inall kinds of weather, are many boaters’first choice. These vents may be pow-

ered, either alone or in combination,by solar cells, an integral rechargeableNicad battery, and/or 12-volt ship’spower. They can be set to function asan intake or exhaust vent as needed.When there’s little air moving over thedeck, a powered mushroom vent pro-vides more airflow than a baffled cowlvent. Solar vents are a godsend forboats that are left unattended for evena few days. A solar-powered fan oper-ates without any drain on the batteryprovided there is sunlight (even mar-ginal brightness). At night, when thereis a slight breeze, it acts as a mush-room ventilator to exhaust or intake air.Combination solar vents provide 24-hour ventilation. Sunlight, when avail-

U P G R A D E

Taller and wider is best when is comes tocowl vents for optimum airflow. A cowlvent with an opening that’s 4" (10cm) indiameter will allow roughly twice the air-flow of a 3" (7.6cm) vent of like design.

(top) Solar vent mounted on hatch providesintake air to aft cabin, resulting in a sweetsmelling boat. (bottom) Solar vents ventilateaft lazarette to minimize condensation andits unsavory side effects.

How a Dorade vent works: baffles preventany water from entering the interior andwater exits via drain holes while air is fun-neled below.

Vetus fiberglasswater trap drainsoff any waterthat entersthrough the cowlvent and can beclosed off in foulweather with theincluded stain-less-steel mush-room vent.

Joe

Van

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nan

able, powers either an intake or exhaust fan and, whenovercast and at nighttime, the fan runs off an internal bat-tery (solar powered).

When using a powered vent, you’ll find that some arequieter than others, either initially and/or with wear overtime. Consequently, it may be better to install a poweredvent in your boat’s head than directly above the V-berth.The fact that powered vents can fail (most often electrical-ly) should be considered when upgrading your boat’s ven-tilation system. If you spend many nights onboard, it’s bestto carry a spare.

Upgrading Your Ventilation System There are no set rules governing how many vents you

should have and where they should be located. A boat’snatural ventilation can travel in any direction, fore and aft,port or starboard. Before you buy and install hatches, portsor vents, experiment with what’s already available on yourboat. When underway, at anchor and in port, adjust yourhatches, ports and vents to optimize ventilation. Use a can-dle (watch out for dripping wax), incense or (worst case ifyou’re smoking it) cigarette or cigar to help you see airmovement and locate dead spots. With experience, you’llfind out what works best and where ventilation needs tobe improved. If you use incense, you’re also likely to meetsome interesting folks from neighboring boats.

Marine stores sell clamshell, cowl, mushroom and solarvents in styles to fit any boat. Vents can be installed in ahatch or through the deck, cabin top or sides. Before cuttingholes in your deck make certain you won’t accidentally becutting through wiring or structural supports. Measure twice,cut once. A saber saw can be used, but a hole cutter of theproper size will give a more accurate cut. Be sure to sealany exposed deck core against water intrusion beforeinstalling the new vent and use an appropriate sealant (e.g.,3M 4200) under the vent flange.


Forward and aft facing hatches and large cowl vents on Doradeboxes offer optimal intake and exhaust ventilation. Underway andin foul weather, hatches may have to be closed to avoid taking onwater. When a boat is left unattended, at anchor or in port, openhatches can also invite thieves. Consequently, it’s best to ensurethat your boat has sufficient vents to provide adequate airflowwhen all hatches are closed. Two or more solar vents added tothis arrangement would prevent cabin air from becoming unbear-ably stagnant when hatches are closed.

Cabin fans, including hardwired 12-volt fixed or oscillat-ing fans and battery-powered portable fans, can be usedto augment a boat’s ventilation system and to increase theeffectiveness of its air conditioning and heating systemstoo. I installed a 12-volt exhaust fan in the head and oneabove the vented propane heater. Later, I used a windscoop(for use when anchored) for my boat’s double-hinged for-ward hatch.

Lockers, Bilges and BunksProviding adequate ventilation through a boat means

storage lockers and bilges must be ventilated as well.Solid locker doors should be louvered or have cane inserts,

grilles or decorativecutouts that allow airmovement. If the lockerdoors on your boat arenot ventilated, they canbe easily modified orreplaced. While wovencane panels (real or syn-thetic) are not typically


35

(left and below) Lowamperage 12-voltfans can be used toaugment a boat’sventilation systemand increase theeffectiveness of its airconditioning and/orheating system too.

(below) Solar pow-ered fan mountedunder a mushroomvent increases theflow of exhaust air incabins and headsand has its ownoff/on switch.

Mounted in the head com-partment is a 12-volt pow-ered exhaust fan in Doradebox duct.S

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36For product info go to www.diy-boat.com


available at marine stores, they are sold by many boat-building supply shops or available from canoe and kayakbuilders who use them in chair seats. (Or search theInternet. Go to www.google.com and search for “wovencane insert or panel.”) Cutouts (with screens or grilles ifappropriate) can also be used in the backs and/or bot-toms of drawers and lockers to provide additional venti-lation.

Condensation that collects on locker floors and undermattresses can be a particularly annoying problem. Heretoo, there are several solutions. Dri-Deck self-drainingventilated vinyl panels are readily cut and custom fit toany locker or bunk. These interlocking “waffle” panelsfacilitate air circulation and the evaporation of moisture.I’ve used them successfully on locker floors for many years.Ventair (www.ventairusa.com), a 1/2" (12mm) thick, three-dimensional nylon mesh with polyester cover, can also beused under mattresses. It’s lighter and easier to moveabout (when accessing storage lockers under berths) thanDri-Dek, and its inherent resilience provides additionalcushioning.

Flow AdjustmentsAs you work to improve ventilation onboard, don’t forget

that you may want to adjust airflow in late fall, winter orearly spring. Most of the ventilation gear available in marinestores is intended for summer use, so you may need to getcreative. When I lived aboard during winters in Maryland,I fabricated sliding acrylic panels to close off the louveredportion of the anchor locker and companionway doors. Iadjusted the airflow from Dorade vents using acrylic discs.Since the discs were transparent, I left them in placethroughout the year.

Use passive cabin“vents,” such as(left) cane door pan-els installed oncabin lockers and(bottom) louveredplastic vents fromMarineEast or stain-less-steel ventgrilles, to facilitateair movementthrough lockers andsmall compart-ments.

http://www.google.com

http://www.ventairusa.com

Insulation Makes a DifferenceWithout adequate insulation, the temperature inside a fiber-

glass or metal boat will quickly respond to the temperatureoutside. When it’s hot outside, it will get hotter inside. And,when the temperature outside falls below the temperatureinside, the hull, cabin and any metal-framed hatches or port-holes will sweat. Wood is a better insulator than fiberglassor metal. Consequently, wood boats and wood-framed hatch-es have fewer condensation problems. Fortunately, the hatch-es on my boat are all framed with wood. I do get condensa-tion on the cast bronze opening ports, but there are teak railsunderneath that will catch and hold drips until they evapo-rate or are sponged away.

Cored (balsa or foam) fiberglass construction, typically usedin fiberglass decks and some hulls, has both thermal andacoustic insulating qualities. If your boat’s hull and deck are

cored, you may find youneed no other insulationto minimize condensa-tion. However, if the hullis solid fiberglass andyou use your boat in coldwaters or cold weather,you’ll very likely want toinstall insulation. Theremany different insulatingmaterials to choose fromso do some research and

pick what will work best for your boat, geographic location,and the type of boating you do. [Ed: For details on selectingand installing cabin insulation, refer to “Smart Cabin Interiors”in DIY 2004-#4 issue.]

Cover-upShielding your boat’s cabin from a hot summer's sun

with a well-fitting awning also helps to keep temperaturesat least 10°F (5°C) cooler belowdecks in summer. WhenI ran my boat’s air-conditioning on hot, muggy days inMaryland, I appreciated the cool air, but disliked the noiseand sense of being “canned.” With a couple of simple (no

(continues on page 39)

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Additional Reading: Cruisers and liveaboards will particularly ben-efit from reading “The Warm Dry Boat” by Roger McAfee(Nighthawk Marine, 2003, 131 pages).

(continued from page 37)battens, no frame) awnings, I didn’t need air-condition-ing during my six years in southern California and Hawaii.

For a relativelysmall amount ofmoney you canmake a dramaticdifference in thecomfort of yourboat. U.S. pricesfor vents (includ-ing deck plates)start at $25 for as ta in less -s tee lclamshell; up to$130 for stain-less-steel low-pro-file or mushroomvents or $30 for aplastic one; $80for a 4" (10cm)screw-in PVC cowlvent and about$350 for thesame size in stain-less-steel with amosquito screenand threaded deckplate plus an extra$161 for a Vetuswater trap; and$200 or less for aday-night solarvent.

Using a systemof both intake andexhaust, passiveand active vents,you can achieve acomfortable levelof cross-ventilationthat will keep

mold, mildew and corrosion at bay. Just imagine having nomore cooking odors, musty air or mildew in the cabin.Good ventilation (and insulation) will help to keep you,your crew and boat happy and healthy. Let your mottobe: “The only good condensation belowdecks is on theoutside of a cold beverage!”

About the author: Susan Canfield is a marine surveyor inAnnapolis, Maryland. A frequent DIY contributor, she also teaches“Surveying Fiberglass Boats” at WoodenBoat School in Brooklin,Maine.

A good awning helps to keep the interiorcooler in summer. (bottom) Passive DavisWindscoop funnels even the lightestbreeze down through the hatch.

Sue

Can

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By Janet Ross

Recently, a client of mine for documen-tation services inquired about “register-ing” various electronic receiving and trans-mitting devices on her boat. She waslooking for one-stop shopping to get allthe ship’s papers in order and handlingthese requirements seemed quite com-plementary to my primary professionalfocus. So, after agreeing to process thepaperwork for all the ship’s needs, I knewI’d be facing a learning curve with theFederal Communications Commission(FCC), the U.S. agency that oversees theuse (and misuse) of the broadcast air-ways, some of which carry signals formarine electronics such as the very highfrequency (VHF) radio. At first, I felt asthough I was looking for the needle in thehaystack as I navigated the FCC websiteon my voyage toward a thorough under-standing of the requirements that affectrecreational boaters and the communi-cation equipment most often used ontheir boats.

I’d anticipated an adventure in bureau-cracy and I was not disappointed. First,determining which equipment neededwhat in terms of licensing or registrationled to having to locate the appropriateforms and instructions for processingthem. I also spoke with friends and asso-ciates that I know are boaters. Few ofthem knew much, if anything, about theFCC requirements for recreational marinetransceiving equipment. They buy thetoys and worry about the rules of thegame later. They don’t see any risks asso-ciated with the status (or lack of it) oftheir VHF radios, including the handheldones they carry when away from themother ship.

E L E C T R O N I C S

Communication

BreakerWhen you get your ship together, make sure you’ve done all thepaperwork to make your communication equipment legal. Here'swhat you need to know about licensing a VHF marine radio,EPIRB and SSB but were afraid to ask.

Radio LegaleseThe Telecommunications Act of 1996

permits recreational boaters to have anduse a VHF radio, an EPIRB and a marineradar without having an FCC ship stationlicense. This change in the law encour-ages boaters to have and use provencommunications’ safety equipment with-out the encumbrances of complex licens-ing requirements. The key word here is“recreational.” Only recreational boatersare exempted from ship station licensing.What is required is that you apply for anew marine radio operator permit or arenewal of marine radio operator permit(as is applicable to your situation). Youcan use a handheld, portable VHF with-out additional licensing as longas the use is ona recreationalboat and you arein “domestic”(U.S.) waters.

Both of these permitscited above require thatyou file FCC form 159,Fee Remittance Adviceand form 605 Quick-FormApplication for a new orrenewal radio operator per-mit and to remit the pro-cessing $55 fee. You can

download all forms andthe instructions for com-pleting them, then fileyour applications andpay the fees electronicallyfrom the United StatesCoast Guard (USCG)website (www.navcen.uscg.gov/marcomms/oth-rcoms/ fcc.htm). All that

having been said, if you have a high fre-quency single-sideband transceiver or amarine satellite terminal or you arerequired to carry a marine radio underany other regulation, you must still carrya FCC ship station license.

Without FCC form 159 you can’t domuch else to advance the FCC applica-tion process. This two-page form mustaccompany any payment to the FCC forall permits. In addition to its function asa remittance form, it establishes your FCCidentity. True to bureaucratic form, thisform comes with three pages of instruc-tions. Once you have completed form159, you can move on to the FCC form605, another two-page fill in the blanks.No other form works so don’t even trythe old FCC 404, 404A, 405A, B, et al.There are nine pages of guidance for fill-ing out the 605 and its applicable sched-ules. There is a silver lining in this cloudof paper and it is that once you’ve done

the paper-work, you canuse your radiob e c a u s eSchedule F

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http://www.navcen.uscg.gov/marcomms/othrcoms/fcc.htm




41

of the 605 becomes your TemporaryOperator Permit. Talk is cheap!

Canadian regulations are not much dif-ferent than those for U.S. recreational boaters.There’s that word (recreational) again. It’sthe key word for both countries. Any personwho uses a VHF radio to transmit must havea Restricted Radiotelephone Operator’sCertificate (ROC) with maritime qualifica-tions, which is a single issue, lifetime cer-tificate. The sole examiner for this license isthe Canadian Power & Sail Squadrons (CPS).Canadians can procure a lifetime ROC byeither taking a VHF course or they can studythe information in the Study Guide for theRestricted Operator's Certificate (RIC-23) athome and then take a short test (fee andpassport photo required) to earn their com-petency and ROC. Anyone who has a cur-rent certificate remains qualified to operatea VHF radio. For more information on theROC, contact the CPS by logging ontowww.cps-ecp.ca or call toll-free to 888/277-2628.

Anyone who uses a VHF radio inCanadian waters must follow the proceduresdescribed in the VHF RadiotelephonePractices and Procedures Regulations.Canada recognizes the American certificate.U.S. and Canada had been working on areciprocal agreement that would have relievedCanadian boaters of certain licensing require-ments when sailing in U.S. waters but thosediscussions were abandoned with the changein security attitudes following 9/11.

As is the case in the U.S., pleasure boatsno longer need a ship station license to usea VHF in Canadian but, if you travel outsideCanada, you may require one. If you takeadvantage of the Exemption of RadioApparatus on Board a Ship, you must stopusing your old callsign. Your name, boatname or hull license number is the substi-tute for the callsign. Your own name is bestas that matches the name you would useon a Float Plan given to the Coast Guard.The exemption applies only in Canadian andInternational waters. In any other country,all stations must be licensed unless there isa treaty between the administrations involved.

EPIRB Timetable One other critical communication device,

the emergency position-indicating radiobeacon (EPIRB), plays a crucial role inlocating boater’s in distress. If you takeyour boat offshore or use it in any openwaters, you should consider taking anEPIRB along for the ride. No moaning

about the cost. The price you pay is neg-ligible when compared to the safety factorshould you ever need to activate it. EPIRBsare designed to save your life by alertingrescue authorities and indicating your loca-tion if you are in trouble. As this technolo-gy developed, several classes and cate-gories of EPIRBs have come and gone,leaving the Category I 406/121.5 MHz asthe unit the USCG recommends. The 406MHz EPIRB was designed to operate withsatellites. The signal frequency is desig-nated internationally for use only for dis-tress. The 406 MHz EPIRB, having anintegral GPS navigation receiver, sendsaccurate location as well as identificationinformation to rescue authorities immedi-ately upon activation. Such EPIRBs are thebest you can buy.

While a FCC ship station license is nolonger required to purchase or carry anEPIRB, there is a registration requirement.Proper registration is mandated by FCCregulations and enforced by the USCG.When you purchase a new or a used 406MHz EPIRB, you must register it with theNational Oceanic and AtmosphericAdministration (NOAA). If you change yourboat, your address or primary phone num-ber you must re-register your EPIRB withNOAA. If you sell your EPIRB, make surethe purchaser re-registers the EPIRB, oryou may be called by the Coast Guard if itlater becomes activated.

Your life may be saved as a result of reg-istering emergency information. Activate aproperly registered EPIRB and the CoastGuard uses the registration infor-mation to immediately begin actionon the case. Your information is sentautomatically to theappropriate USCGSearch and Rescue(SAR) RescueC o o r d i n a t i o nCenter (RCC) forresponse who thencontact the emer-gency phone num-bers you providedon the registrationform. You shouldfrequently updateyour contacts withas much aboutyour intended voy-age as possible.The more information given, the bet-ter prepared SAR personnel can

react. Download 406 MHz EPIRB regis-tration forms from the NOAA SARSAThomepage (www.sarsat.noaa.gov), thenmail or fax completed forms to SARSATBeacon Registration, E/SP3, Rm 3320,FB-4, NOAA, 5200 Auth Road, SuitlandMD 20746-4304. For further informationor to request registration forms call toll freeat 888/212-SAVE (7283). From outsidethe U.S., call 301/457-5430 or fax to301/568-8649. There is no charge forthis service.

The online registration capability is asignificant advantage to EPIRB ownersand they can update their registrationinformation as often as it changes. It'simportant to note, however, that your reg-istration is valid for only two years. Youare required to re-register your EPIRBevery two years so that contact informa-tion is up-to-date.

Canadian boaters carrying an EPIRBmust register them with the NationalBeacon Registry at 800/727-9414. Inearly 2005, it's expected that GlobalMaritime Distress and Safety System willbe added to the course and the ROCexam.

The air is free and so are the airwaysbut using regulated communication equip-ment legally does require attention to afew licensing details.

About the author: Janet Ross heads up theyacht documentation division of a marineservice company in Naples, Florida. DIYreaders can pick her brain [email protected].

Pat

Kea

rns

http://www.cps-ecp.ca

http://www.sarsat.noaa.gov

anode wear. Give it a squeeze and itmight turn to powder in your hands.

Continuity CheckThe boat must be hauled out of the

water to perform a continuity check todetermine if anodes are in continuitywith the engine ground. Using a digitalmultimeter (preferably one that reads inmilli-volts and milli-ohms), connect theblack lead to the engine ground and usethe red lead to contact each sacrificialanode. The reading should be no morethan 150 milli-ohms. If resistance ishigher, clean the contact between theanode and the sterndrive and thenrecheck. If the value is still too high, oneof the continuity conductors is likelymissing or broken. Also check the blackcontinuity wire between the engine andthe transom assembly. Replace anywires that are broken, frayed or thathave cracked insulation and then, launchthe boat.

Potential TestingA hull potential test determines if

anodes are, in fact, protecting the stern-drive. The boat must be in the waterfor at least eight hours in its usual moor-ing location prior to performing this test.You'll need a reference electrode and adigital multimeter. (Electrodes are avail-able from Mercury Marine dealers, part

91-76675t1, for about US$100.) Setthe multimeter on DC millivolts.Connect the black lead to battery neg-

By Steve Auger

Most boat owners know about theeffects of corrosion. Repairs due to cor-rosion damage are very expensive,especially if a new drive is required.There are two types of corrosion: gal-vanic and stray current corrosion.

Galvanic corrosion takes place whentwo dissimilar metals like stainless steeland aluminum are bolted (bonded)together and then submerged. Stainlesssteel is a noble metal, so it’s consid-ered as the more stable of the pair andis referred to as a cathode. Aluminumis less stable and as such is referredto as an anode. When the two metalsare submerged, electrons flow out ofthe aluminum into the stainless steel.This current flow consumes the alu-minum thus causing corrosion. Oneway to deter this migration of electronsis by installing a “sacrificial” metal, onethat is intended to have its electronsconsumed. This metal becomes a sac-rificial anode, wasting away (from elec-tron loss) on purpose. Modern anodesare made of zinc (for saltwater appli-cations) and magnesium (for freshwa-ter applications). Both are more anod-ic than the aluminum components onthe drive unit. These anodes corrodesacrificially so that the more noble met-als (stainless steel, aluminum) can sur-vive. In order for this type of system towork all sterndrive components mustbe in continuity with the engine ground(battery negative) and anodes must bein good condition. Anodes requirereplacement when they are 50% con-sumed, which is typical of saltwaterboats, or become covered with marinegrowth on freshwater boats, which actslike an insulator. Never rely on theanode’s appearance to determine

E N G I N E

Corrosion

ProtectionKnowing what causes corrosion and how to test for it will ensure yoursterndrive unit is protected from being eaten by corrosion’s effects.

All sterndrives have sacrificial anodesmade of an alloy that is more anodic thanthe aluminum alloy used in the drive unit.Anodes are located: (from the top) abovethe anti-cavitation plate; as the trim tab;and underneath the transom near the trimcylinder.


42

Anodes must be in contact with water(the electrolyte) to work. Paint preventsanodes or the Mercathode electrodeassembly from protecting the drive unitagainst corrosion.

TIP: Never Paint

ative and, using anapproximately 3' to5' (88cm to 152cm) long woodenpole (an old broomhandle works),dangle the refer-ence electrode,which has beenconnected to thered lead, about 6"(15cm) from thepropeller withoutletting it actuallytouch it or thesterndrive. In salt-water, the metershould read no lessthan 850 millivoltsand no more than1,100 millivolts. Ifthe value is below850, there is insuf-ficient anodic pro-tection. If all anodesare grounded cor-rectly and in goodcondition, you mayneed to invest in anelectronic galvaniccontrol device, suchas the Mercathodesystem offered byMercury Marine.Where the meterreads above 1,100millivolts, there istoo much anodicprotection, whichcan lead to paintblistering or pitting.Hit the sweet spot,around 1,000 mil-livolts, and theengine's covered.

The same process applies in freshwater; however, the voltagevalues are 750 millivolts minimum and 1,050 millivolts max-imum. Around 900 millivolts is ideal for freshwater use.

AC Voltage Galvanic corrosion also occurs in boats equipped with

shorepower. This takes place when voltage flows from themarina's electrical box, through the green neutral safety cir-cuit, which connects to the sterndrive engine ground circuit.Because the sterndrive is in continuity with the shorepowersupply, this current attempts to seek a natural ground as itflows out of the boat and corrodes the sterndrive. A shore-power galvanic isolator, such as the Mercury Galvanic Isolator(part 888557T010, $350) uses a diode network to take the


The 12-volt Mercathode system acts as anelectronic sacrificial anode and consists oftwo components: (top) a reference electrodeand anode in a single housing that connectsto the gimbal housing and a (bottom) con-troller that installs on the engine. This systemrequires water to operate and automaticallyshuts off when the boat is hauled.

Besides the engine ground wires (shown),the continuity circuit consists of strapsmounted near the steering lever, bell housingand gimbal ring, plus ground plates, starwashers and washers.


44

corrosion. Stray current corrosion alsotakes place in the bilge when the bilgepump or bilge blower supply wires areimproperly connected and are sub-merged in bilge water. Always installelectrical connections well above thenormal bilge waterline. Use heat-shrink,adhesive-lined terminals and separatebusbars for positive and negative(ground) connections. Be sure engine

battery cables are the correct size, ingood condition and supported highabove the bilge, well clear of normalbilgewater levels. Mercury offers a pub-lication called Marine CorrosionProtection Guide, $2.50, part 90-881813-01 that details all causes andcures of marine corrosion.

About the author: Steve Auger has more than35 years experience servicing all makes ofoutboard and stern drive engines. He is DIY'sengine technical advisor and service traininginstructor/Mercruiser product support special-ist at Mercury Marine.

boat out of continuity with the shore-power ground yet still allows the cur-rent needed to supply the boat's110/120 volt AC panel, thus protectingthe sterndrive. If you already have a gal-vanic isolator and suspect that it's notfunctioning correctly, you can have iteasily tested by a qualified marine tech-nician.

Wiring AmissStray current corrosion occurs when

current leaves its normal path for a pathof less resistance. Corrosive effects takeplace with much more dramatic resultsand in a much shorter time than gal-vanic corrosion. The most commoncause of stray current corrosion occurswhen wiring with damaged insulationbecomes submerged, exposing barewire. Current then flows through the

aluminum sterndrive or engine oil pancausing severe corrosion. For example,if your sterndrive transom assembly hasmassive corrosion on the port side only,the wires to the trim limit switch arelikely damaged causing stray current

ENGINES

This photo illustratesthe position of thereference electrode,in relation to thepropeller and stern-drive, to test hullpotential. This test isalways conductedwith the boat in itsusual mooring for atleast 8 hours prior tothe testing.

Keeping the sterndrive clean, touching-up any exposed metal with fresh paintand then applying a quality wax all aidin preventing galvanic corrosion.

TIP: Curb Corrosion

A Mercury Galvanic Isolator passes AC but not DC currentand installs in the boat's shorepower grounding conductor tobreak the grounding circuit.

By Jan Mundy

As any professional painter will attest, sur-face preparation is one of the most impor-tant elements of an effective paint job.Experience has shown that little thingscan cause major problems when it comesto preparing a boat for painting. Start witha clean surface and keep the surface cleanthrough all of the steps. Contaminationincludes oil, wax, sanding residue andmoisture. Moisture causes problems withprimers and finish coats when it becomesentrapped in the primer (more about thislater).

The first step in a painting job is toremove any contaminants that may be onthe surface, such as grease, oil or waxthat will ruin a paint job. Waxes contain-ing silicone or Teflon are especially hardto remove. Sanding or sand blasting doesnot remove surface contamination. In fact,sanding or sandblasting an oily or waxysurface will cause the contaminants to beground into the surface, making it hard-er to remove. Surface contamination caus-es fisheyes or craters in the paint or evendelamination of the coating.

Start by washing the surface to bepainted with soap and water using a stiffbristled brush or Scotch-Brite pad and a lotof elbow grease. Be sure to rinse thor-oughly to remove the soap residue. Afterwashing and rinsing the hull, degreasethe surface with a solvent that is manu-factured especially for cleaning, such asInterlux Fiberglass Solvent Wash 202 orSpecial Thinner 216. Use two rags whenwiping, a rag soaked with the cleaningsolvent and a clean, dry rag. Wipe thecleaning solvent over a 4 sq.ft (.37 sq.m)area and then come back over the samearea with a clean dry rag. Change rags

frequently to ensure removal of all con-tamination; otherwise, you are just movingit from one place to another. When clean-ing, pay special attention to areas aroundexhaust ports, under fuel vents, placeswhere teak oils can come into contact withthe fiberglass or metal and areas wherefenders rub against the hull, as these aremore difficult to clean. Repeat this process

until the entire surface is clean. To be cer-tain that all wax and other contaminantshave been removed, spray water over thesurface. If the water beads up, wipe againwith Interlux Fiberglass Solvent Wash 202.When the water sheets off, you're readyto paint.

Undercoating Once you are satisfied that the surface

is fair, one or two coats of primer or under-coater is often applied. Color changes areeasily noticed through the finish coats andprimer colors are chosen based on howclosely they match the finish color. Primerselection is also based on the choice offinish paint. A two-part polyurethane, forexample, often uses a different primerthan a one-part paint.

After the final application of primer/undercoater, more sanding is required.Start sanding with 120-grit to 150-gritpaper to remove any mistakes thatoccurred in application such as orangepeel or sags. Leave the recommendedanchor pattern or “tooth” when sanding.Too much and the sand scratches show

The quality of the finish and durability of thepaint is only as good as the prep work.

PrimeCoatsFollow these steps from the pros to prepare surfaces forpainting, to apply antifouling to aluminum, fiberglass andsteel boats and underwater running gear, to varnish or oilbrightwork and to refinish interiors, aluminum fittings, bilgesand vinyl cabintops.

M A I N T E N A N C E

Look for areas that bead water, meaningthere is still wax present and you need toreapply the cleaner and scrub more aggres-sively.

Surface contamination caused an orangepeel effect on this surface coated withToplac, a one-part polyurethane paint.

Properly prepped gelcoat receives a coat ofprimer applied with a natural bristle brush.


45


46

through; too little and the paint will notadhere. The final sanding for topside fin-ishes is usually 320-grit wet or dry sand-paper; 80 to 120 grit for antifoulingpaints. After sanding the primer, removethe sanding residue by using a cloth,dampened with the thinner that you areusing in the paint. Using a compatiblethinner eliminates any problems with theprimer and, should any solvent residueremain on the surface, it's fully compati-ble with the next coat.

Too much moisture causes loss of glossor, even worse, can cause coatings to blis-ter when overcoated with primer or finishcoats. It's best to sand the primer andapply the topcoat the same day if possible,especially when working outside.

Sand by Number It’s always best when sanding to sand

“through the numbers.” That means that,if you start sanding a surface with 80-gritpaper but need to end up with 220-gritpaper, then you must sand the surfacewith 120 paper, then 150 paper, then180 paper and then, finally, 220 sand-paper. This results in a smoother surfaceby ensuring that all of the sand scratch-es from the previous sandpaper areremoved. Sanding with 220-grit sandpa-per will not remove the sanding profile leftby 80-grit paper or 120 for that matter.

Never sand by hand because you’llcause directional scratches that are diffi-cult to sand out. Instead, use a dual-actionsander with a soft interface pad and acontact paper, such as 3M Hookit or 3MStikit discs. This produces swirl marksthat are much easier to sand out (“throughthe numbers”) than directional scratch-

es. For sanding little spot repairs, use pre-cut scallop disks that adhere to a fingerpad. Dry sanding tends to cause point-loading, where sanding dust embeds itselfinto the sandpaper causing a deeperscratch. Using freecut papers that con-tain a dry lubricant reduces pointloadingbut not completely. Cleaning the paperfrequently with a Scotch-Brite Clean &Prep Scuff Sponge helps to remove someof the accumulated sanding dust. Alwaysdisconnect the power when cleaning thepad or changing paper. Pointloading is theone downfall of dry sanding, though it’smuch faster than wet sanding. Wet sand-paper, conversely, last's much longer andis self-cleaning. Always pre-soak a wet-paper before using to soften the paper.

Use it with a soft pad or 3M Scotch-BriteClean & Prep Sponge. Never wrap wet-paper around fingers or you'll get indentsin the surface. It's best to cross-sand,changing direction when wet sanding, toeliminate directional scratches.

Masking TricksMasking tape is are one product where

cheaper is never better. You already knowthis if you've had the unfortunate experi-ence of scraping off a gluey mess afterusing the inexpensive, light colored, run-of-the-mill stuff on your boat. If you insiston using inexpensive masking tape, neverleave it on for more than two to threehours in sunlight. Certain 3M Marine tapescan be left on until the job is complete.3M Long Mask is good for up to sevendays; 3M 2080 Safe-Release tape worksfor up to three months without leaving anadhesive transfer. It’s best to removemasking tapes when the coating is slight-


(top) A painter’s sanding kit includes 3MHookit discs, freecut dry sandpaper andwetpaper in various grits, and scallop discsand pad. (bottom) Clean dry sandpaper witha Scotch-Brite Clean & Prep Scuff Sponge toremove accumulated sanding dust andextend paper life.

ly tacky. (Tip: always pull off tape at a 45° angle to the tapedline.) A trick used by professionals when painting multiple coatsis to first apply a 3M weather-resistant tape then overlay it witha cheap masking tape. This outer tape is removed after everycoat, leaving the good tape in position to mark the line. Retapewith the cheap stuff before applying the next coat.

Temperature CountsSanding and prepping when the weather is cold is not a

problem except for the person doing the work. Applyingantifouling paints should be done when the air and hull tem-perature is above 50F (10C). The reason for this is to makesure the paint dries thoroughly and cures properly. Antifoulingpaint is applied in a fairly heavy coat, 4mils to 5mils wet,which equates to about five sheets of standard copypaper. Ona cold hull, the paint dries on the outside (closet to theatmosphere) but thoroughly dry (closest to the hull surface)can be a problem. Copolymer antifouling, like Micron, willwear faster while a hard paint, like Fiberglass Bottomkote, willnot be as hard as designed and will begin to wear duringthe season and may even flake off when hauled out for win-ter storage. If you cannot paint in ideal temperatures, you'rebetter to apply soft bottom paints, like Red Hand, Bottomkoteor Bottomkote XXX, which dry okay when temperatures fallbelow 50F (10C). VC17m, a hard antifouling, also driesdown to 40F (5C).

Where the bot-tom finish is ingood condition, allthat's required is athorough washwith a boat soapfollowed by a lightsanding to providesome tooth for thenew paint to stickto. As the surface

is already wet, my preference is to wet sand with 80-gritwetpaper. It saves time waiting for the hull to dry and youhave little concern for toxic sanding dust. I wear latex glovesand an old foul-weather suit with the cuffs and legs tapedto protect skin from the toxic residue. I used to apply antifoul-ing paints with a foam roller and, even though it had a sol-vent-resistant core, it still disintegrated, leaving foam bitsover the wet paint. Now, I use a 2" (5cm) thick sponge. Itdoesn't dissolve and when it starts to compress from theweight of the paint, I simply toss it out and grab anotherone. Be sure to don thick rubber gloves if you use this appli-cation method. The result is a smooth finish free of any airbubbles or brush strokes.


Other than a wornwaterline, this boat’sbottom paint is ingood condition andrequires just a thor-ough washing, lightsanding then recoat.

The author’s preference is to wet sand bot-tom paints before reapplying a new coat.


48

It's common to run the antifoulingpaint up to 3" (7.6cm) above the actu-al waterline and then paint the boottop. There are paints sold specificallyfor boot tops or you can usepolyurethane. To apply, wash the hull,degrease with solvent and then sandwith 120-grit paper. Tape the line using3M Long Mask and apply two to threecoats with a natural bristle brush or a3" (7.6cm) roller followed by a brush(the roll and tip method) if the width ofthe boot top allows. A quart would suf-fice with some left over for touch up. Ifyou need to locate the boot top-water-line, use the water hose method. [Ed:This is detailed in DIY 1997-#4 issueand also on the MRT “Painting &Refinishing” CD-ROM.] Tip: For a clean-er waterline spray with Captain PhabPro-Tect (wwwcaptainphab.com).

Wood CareNewly varnished, gleaming brightwork

looks elegant and gives a boat “yachty”appeal but maintaining wood finishes

comes with a high labor pricetag.Constant exposure to salt, humidity andsunlight can rapidly deteriorate varnish-es and other finishes like oils, as well.Ignore brightwork and it peels, the woodbecomes weathered, even black fromexposures to water, dirt and pollutantsin the atmosphere. Failure to prepare thewood properly or apply the recom-mended number of base coats and thecoating soon begins to peel. (I swear mynext boat will have no wood on the exte-rior.)

There are several kinds and qualitiesof marine varnish. They run the gamutfrom traditional “natural” varnishes toman-made polyurethane or urethaneclear coatings, in either solvent or waterbased flavors.

Natural products are classed as “soft”coatings, for they are flexible; man-made varnishes are harder and morebrittle, making them the best choice onsurfaces subject to foot traffic, wear andchafe (cabin soles, cockpits, rubrails,etc.)

Like paints, all varnishes and oils

There’s nothing quiet so elegant as newlyvarnished woodwork.

Regardless of the protective coating youchoose to use, maintaining that coating iskey to preserving the finish and wood under-neath.

To renew a teak and holly veneer cabinsole, wash with TSP then lightly sand with180 grit. The coating of choice is UltimateSole, which provides a durable, glossy fin-ish with non-slip properties.

Use this formula to estimate squarefootage below the waterline: boat lengthtimes beam times .85. Remember todouble that amount for two coats andtriple for three coats.

Tip: How Much Footage?

work best at 70F (21C) and should never be applied in directsunlight or in high humidity. One-part traditional varnishesrequire a build up of six to 10 coats, followed by one or moremaintenance coats annually. Two-part varnishes have theadvantage of requiring fewer coats (three is normal). By dry-ing faster, they also pickup less air suspended dust so theyrequire less sanding between coats.

Apply several thin coats rather than fewer thick ones,which take longer to dry. When applying on bare wood, it'sadvisable to seal the wood by thinning the first coat by 50%and lightly "wet" sanding to remove any raised grain. Betweeneach coat, sand with 280-grit to 400-grit dry paper or rubwith fine bronze wool to eliminate dust particles. To elimi-nate sanding between coats try Epifanes Woodfinish. It'seasy to apply, doesn't require sanding between coats and iscompatible with traditional varnishes. It dries overnight andcan be recoated without sanding within 72 hours of the pre-vious coat. This means that you can apply seven coats inseven days.

Of the oil finishes, Cetol remains the coating of choicefor most boaters. You'll get a more durable finish if you applythree coats of the mat (Marine Light) followed by two coatsof the gloss, waiting 24 hours between coats. A new prod-uct that shows merit is Amazon's Teak Lustre from MDR(www.mdramazon.com). This single-part water-based acryliccoating for teak dries within 15 minutes and is sandable in45 minutes. This means that you can easily apply the rec-ommended three coats in a single day. One application claimsto keep teak looking great for up to three years. Better yet, itcan be applied directly over Amazon’s Teak Oil (do a spottest first before overcoating other teak oil brands.) Teak Lustreis non-toxic, contains no VOCs, clean up is with water andit doesn't change the surface color of the teak. When refin-ishing a teak and holly cabin sole (floor) you can use var-nish (slippery) or apply Ultimate Sole, which offers a glossylook without the slip.

Interior Refinishing When paint peels on interior spaces, it's likely that the sur-

face was never properly prepped. Old paint suffering from pooradhesion must be stripped. There is no magical, “easy” methodhere. Don't use heat stripping, which can damage the sub-strate beneath it. Some chemical strippers are safe to use ininterior spaces but these tend to make a mess. A better


Over the years, these words have become almost inter-changeable but, when it gets down to basics, a primer itsomething that is put on the substrate and an undercoateris used in relation to the finish. You prime the aluminum orfiberglass or even over a previously painted surface. You canuse an anti-corrosive primer on steel. Undercoater is usedunder the finish to improve the surface. Paint companieshave produced products that do both so that work time isreduced and the job is made easier.

What’s the Difference between Primer and Undercoater?

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50

approach is to knock off any loose paintwith a paint scraper and remove the restwith a dual-action sander and 80-gritsandpaper discs (i.e. 3M Hookit discs).Wear a full faceshield and a disposableTyvec paper suit with hood. A respiratoris also strongly recommended. On olderboats, old paint could contain lead pig-ments so you should be very cautiouswith the dust.

Make sure the surface is thoroughlyabraided and then sand by the numbers(see page 46). Clean off all dust andapply at least two coats of a one-partpolyurethane (i.e. Interlux Brightside orToplac) or marine enamel. The objectiveis to end up with a reasonably glossysurface that is easily cleaned, so thatshould mold form, it can't gain afoothold. (Mold prefers a porous surfaceas it's easier to put down roots.)

Barnacle-ProofingUnderwater Metals

According to the experts at Interlux,there is an antifouling method to protectbronze and stainless-steel shafts, struts,props, trim tabs, thru-hull fittings andeven stern thrusters from barnacles.Painting these areas requires specialattention to initial surface preparationin order to improve adhesion.

The idea is to isolate the copper inthe antifouling paint from the bronze ofthe strut. The cuprous oxide in theantifouling paint is less noble than thebronze in the strut and if you don'tprime properly, the paint's antifoulingproperties will be compromised. Theresult of not properly priming the bronzecould be loss of antifouling protectionand the strut will become fouled or burnback may occur. Burn back looks justlike it sounds, the paint looks as if ithas been burned in concentric circles

emanating from the strut or thru-hullor strainer.

The longevity of this system will prob-ably not equal that of the remainder ofthe boat bottom, due to the abuse ofthe service speeds (rpm) these partsmust withstand. However, excellentresults have been obtained using thefollowing steps. First, degrease themetal surface with Interlux FiberglassSolvent Wash 202 or Special Thinner216. Next, bring metal to a uniformbright finish by sandblasting with non-ferrous blast media, such as clean sili-ca sand, or grind using coarse to medi-um emery cloth. Solvent wipe toremove blast or sanding residue.Immediately, apply one thin coat ofInterlux Viny-Lux Primewash 353/354thinned 25% with Viny-Lux Solvent355. If this is not done within 24 hoursof blasting or sanding, you'll need toreblast or sand with coarse emery cloth.Primewash is a metal etcher contain-ing vinyl butyral resin, phosphoric acidand a little bit of zinc chromate. Theacid cuts through the oxidation and thevinyl resin gives the primer something tohold onto and the zinc chromate addssome anticorrosion protection. Metaletchers are the weak link in the chainand instructions must be followed verycarefully.

Allow Viny-Lux Primewash 353/354to dry a minimum of one hour but nomore then 24 hours and apply fourcoats of Interprotect 2000E/2001E fol-lowing dry times on the label. If fairingis necessary, fair between first and sec-ond coats of Interprotect.

If you don’t want to prep the geardown to bare metal, coat the surfacewith two to three coats of a single-partprimer, such as Primocon and thenapply the 2000E. Apply two to threecoats of a non-vinyl antifouling paint.Hard antifouling paints work best suchas Fiberglass Bottomkote or Ultra forthis application. On aluminum use Trilux33, Trilux or Tri-Lux II. Note: if dry timesfor Interprotect cannot be followed, usethe following alternate system. Applyfour coats of Primocon YPA984 overthe Viny-Lux Primewash 353/354. Onrivets and welded seams apply a min-imum of five coats. Finish with at leastthree coats of antifouling paint.

Aluminum Like NewIt's not difficult to restore aluminum

fittings, such as a ladder, rubrail, tower,etc., it's just labor intensive. When alu-minum begins to show its age, have itsurface blasted if the part is easilyremoved or, if not, grind it to “bright”metal. Apply one coat of zinc chromateetching primer (i.e Interlux Viny-luxPrimewash 353/354), followed imme-diately with an epoxy primer/surfacersuch as Interlux Epoxy Barrier-Kote404/414 or Awlgrip 545. Metals, espe-cially aluminum, begin oxidizing imme-diately when exposed to the air and thelonger that oxidation builds up the moredifficult it is to coat. Finish with apolyurethane topcoat of your choice.The epoxy primer may or may not needsanding depending on the exact coat-ing system and overcoat interval.

When painting aluminum, it's a goodidea to apply extra coats of primer overriveted or welded areas. These areasneed extra care as the rivets are seldommade of the same grade of aluminumas the boat.


If you’re unsure what type of antifoulingpaint is currently on the hull, yet the coat-ing is in good condition and adhering,rather than remove it, brush or roll onPrimocon primer. This improves adhe-sion and prevents cracking of the newantifouling paint. It’s compatible with allantifouling paints except VC and VC17.

Tip : Easy Fix for Old CoatingsNo antifouling onthis outdrive resultsin excesive drag,slower speeds andincreased fuel con-sumption. Anantifouling special-ly formulated foraluminum out-drives, such asTrilux Prop & Drive,is the solution.

Final coat of Interprotect 2000E applied torunning gear.

(Continues on page 52)

Once you’ve decided you’re ready for a new boat, you don’t want

anything to slow down the process. So before the wheeling and dealing

begins, make sure to have all your loose ends tied up neatly.

BoatU.S. Members have access to a number of valuable online

services such as FREE estimates of the fair market value of your boat as well

as FREE insurance quotes and affordable financing.

We will also handle the cumbersome details of your transaction such as

escrow, settlement and documentation services at BoatUS.com. These

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at BoatUS.com

Visit the Boat Buyer Services page at BoatUS.com Today! It’s a one-stop source of information that can help the process of buying or selling a boat go as smoothly and quickly as possible.

BBS_SEPT07ducks.indd 1 8/3/07 4:03:00 PM





52

Steel TreatmentsAccording to DIY's shop expert Nick

Bailey, the best coatings for steel boats,when you compare cost versus per-formance, are not the yachty paints youbuy at marine stores or even the con-sumer-oriented renovation and con-struction paints found at hardware storeslike Home Depot. What you want areindustrial coatings used in shipyards andheavy marine construction like offshoreoil derricks. These high-performancecoatings are cheaper and often easierto use but may not have the broadercolor selection. Nick’s preference isDevoe Coatings, a division of Ameron(www.devoecoatings.com/index-work-ing.html). These paints can usually onlybe purchased from a wholesale distrib-utor. If you are lucky, the small quantity(a gallon) packaging may be available.Devoe Bar-Rust (several versions) is afantastic epoxy anticorrosion primer.There are also cheap antifoulings (theABC series), urethanes and epoxy top-

coats and Devgrip 189, a slip-resistantcoating.

Bilge Clean-up Painting accessible bilge areas with

a high-gloss, smooth finish coating helpsto keep dirt, grime and mold (can’t stickto a smooth surface) from accumulat-ing in bilge. If the fiberglass is in goodcondition begin by scrubbing well usingsoap and water and a stiff brush. If nec-essary, wash all surfaces with a 3%beach solution to remove any moldspores. Rinse with freshwater and allowto dry. Degrease by wiping with a ragsoaked in Fiberglass Solvent Wash 202or use Fiberglass Surface Prep YMA601.Sand with 180-grit paper then vacuumup the sanding residue and follow witha tack rag. For surfaces in poor condi-tion, clean as above then sand with 80-grit paper. Apply PreKote 4279. Nowapply one or more coats of InterluxBilgeKote to bilge areas. Be sure to weara respirator and use fans to ventilate thecabin and bilge.

Recoating Vinyl Some older cruisers have a white

vinyl (not canvas) material, similar tothe fake convertible tops on cars, overthe cabintop. When this becomes dingy,you’ll want to clean it. Conventionalmarine paints are normally not recom-mended for this purpose because oftheir hardness. Due to the flexibility ofthe surface, the paints would be proneto cracking. Some people have had suc-cess using paint like Interlux YachtEnamel because it’s not as hard as theone-part polyurethane paints. You haveto be careful to apply it in thin coats. Abetter alternative is to apply MDRInflatable Top Coat #784. To apply, firstdegrease the top with MDR Crazy Cleanor similar to remove all oil, grease evenfingerprints. Don’t use a solvent as itbrings plasticizers to the surface andmakes the vinyl tacky so nothing sticksto it.

— with contributions from Nick Bailey andJim Seidel of Interlux Paints.

Did you know that…

…performance of solvent-based paint strip-pers is greatly reduced at low temperatures.Optimal working temperature of Interlux 299,for example, is 50F to 70F (10C to 21C).

…even if your paint was mixed at the store,stir it thoroughly before each use. Antifoulingpaints require periodic stirring in the can orroller tray while applying.

…if you apply varnish with a foam brush,sponge or soft cloth, you won’t end up withvisible brush strokes over any portion of thefinish.

… a “hazy” or glossless finish generallymeans that moisture from dew, rain or sim-ply extreme humidity has entered the fin-ish prior to the film drying.

…you can keep your aluminum sterndriveclean by coating it with Trilux Prop & Driveor other antifouling formulated for safe useon aluminum components.

…on decks, two-part polyurethane worksbest because it resists abrasion better than

one-part urethanes.

…you cannot overcoat a two-part with aone-part polyurethane paint. To check, ruba small area with a cotton swab dippedin acetone. If the paint dissolves or wrin-kles within 10 minutes, it's a one-partproduct.

…a quick humidity check is to wet a smallarea and, if it dries without 15 minutes, it’sokay to paint. If it doesn’t dry, it’s too humid.

…once you’ve selected your paint, do acompatibility test. Select a small, incon-spicuous spot and apply one coat. Cross-hatch the surface with a sharp knife, laysome masking tape overtop and pull off. Ifthe paint comes off, you’ll need to removethe existing finish.

…a better tack rag for removing dust beforevarnishing are 3M Scotch-Brite “dry”Performance Cloths. These lint-free clothscan be used with solvents, are reusable(wash as needed) and don’t need to bestored in a sealed plastic bag.

…a frequent application of a spray wax(e.g. 3M Clean & Wax that adds a new doseof UV-inhibitors, will extend the life of anexisting painted or varnished coating.

…to preserve a polyurethane finish, suchas Awlgrip, Imron or Interthane, wash thesurface frequently with Awlwash WashDown Concentrate (73234), diluted asspecified on the label. Rinse well and wipewith a clean chamois. Don’t let this clean-er dry on the surface. Follow with AwlcareProtective Polymer Sealer (73240) to main-tain and/or restore the gloss. Never washthe topsides with marine soaps or any clean-ers containing alkalis, acids or abrasives.

…3M Marine has a Perfect-it system forpainted finishes that includes a color restor-er and glaze. If you have applied the Awlgripprotective gloss and are unable to regainthe gloss, the Perfect-it system will revivethe paint and give you a few more yearsbefore the surface needs repainting. Perfect-it is available from many auto detail-ing shops.— JM

�

(Continued from page 50)

http://www.devoecoatings.com

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53

a plane, the extra weight forward tips thebow down and the boat comes off plane,which brings the hull back into balanceand lets it get onto a plane again. Whenthis motion continues and results in aseries of on/off plane performance, theboat is porpoising, which can only beeliminated by moving weight farther aftuntil the boat trims level both in dis-placement and planing mode. This effectcan also be reduced by trim tabs andwedges, both of which are discussed later.

To maximize trim you need to consid-er where to stow all heavy objects, suchas batteries and anchors. The best prac-tice is to concentrate the heaviest weightsnear the hull centerline. Never try to bal-ance a heavy weight in the bow withanother heavy weight aft. Suppose youadd anchor chain and a heavy anchor tothe bow on a boat not designed for them,putting the bow down by a considerableamount. Then, you mount the dinghy afton the swim platform to balance theincreased weight forward. Not a goodidea. You’ve now hung heavy weights offboth ends, resulting in a see-saw effect,producing another unpleasant and poten-tially dangerous motion that lessens yourenjoyment of the boat.

On the LevelSo, how do you ensure that your boat

will float level? The easiest way is to putit in the water and adjust gear until youget level trim. What happens when a newboat is launched and it floats out of trim?In the old days, builders would surrepti-tiously launch the boat before the officiallaunching date, check the trim and bootstripe level, haul the boat, correct anytrim problems by putting strategicallylocated lumps of lead in the bilge, repaintthe boot stripe in the right place and thenlaunch the boat again for the official

launching. Today, designers use sophis-ticated computer programs to determineexactly where the boat should float. Still,builders surreptitiously launch the boat,check the trim…correct any trim prob-lems... .

Entering WedgesIf you, like me, have an older planing

boat and you stick a heavy four-strokeoutboard motor on the stern, your boatwill probably float like mine does, sterndown. While this is not a major disad-vantage on a small boat, which tends tohave more horsepower than needed, it'sa slight disadvantage when it comes togetting a larger boat on plane.

The best approach is to adjust the trimangle. According to Lindsey Lord’s book,

By Roger Marshall

“How’s your trim?” I was asked manyyears ago when setting up a racing boat.“No idea,” I replied, not quite sure if Iwas being asked whether it was my selfor the boat whose trim was in question.“Was it level, down by the stern or downby the bow?” Now, I understood thequestion, though at the time I had noidea that trim affects performance.

Trim is the fore and aft “attitude” of theboat. A boat that is down by the stern,with its transom deep in the water, is slowto plane and hard to keep on plane. Italso causes a large wake when in dis-placement (non-planing) mode (i.e. wakeboarding boats are deliberately trimmeddown by the stern to generate a largewake). Stern-down trim is usually causedby too much weight aft. With the currentgeneration of four-stroke outboard enginesreplacing lighter two-stroke engines, manyolder designs tend to trim down by thestern.

When a boat is down by the bow, italso has difficulty getting on plane. Ittends to push water in front of it, and itmight have a very wet foredeck (bowdeck area). In a seaway, trim down bythe bow can be dangerous. Bow-downtrim is often caused by installing anchorchain too far forward in a boat that is notdesigned to carry it. When you figure thatan anchor for a 30' (9.1m) boat canweigh 25lb to 30lb (11kg to 13.6kg),that a windlass weighs about 40lb(18kg), and that 200' (61kg) of 3/8"(9mm) chain weighs 340lb (154kg), youcan see how easily this problem arises.Locating this much weight forward in theboat is equivalent to having two largeadults permanently standing on yourboat’s bow. When such a boat gets onto

P O W E R B O A TR I G G I N G

The Trim TruthA boat that has bow-down or stern-down trim will typically moveslower through the water, give a wetter ride, is slower to planeand generally doesn't “feel” good at the helm. Balancing triminvolves rearranging gear, adding stern wedges or installing trimtabs. Here's how.

Author's boat floats stern-down, as noted by the white boot stripe, after mounting a heavyfour-stroke outboard.

Trial and error is the only means to accu-rately determine the length and depth of atransverse wedge.

Transom

Bottom

Length?

Dep

th?


54

POWERBOAT RIGGING

“Naval Architecture of Planing Hulls,”the ideal planing angle is around 3° to5° of bow-up trim. There are several waysto obtain this angle. The easiest is tomove crew around until the boat istrimmed properly. Another way to get theideal planing angle is to install a wedgeat the stern. This is a transverse wedgerunning across the boat bottom at thetransom. Its size depends on the size ofthe boat. For, let’s say, a 24-footer (7.3m),it might be only a 1/2" (12mm) deep atits thickest (trailing) end and 18" (46cm)long. There are no hard and fast rules forwedge size. You need to sand or shavethickness off the wedge to get it to workat its optimum potential. One story tellsabout a powerboat around 90' (27.4m)long that had a wedge fitted. It washauled and launched several times whilethe architect measured trim at accelera-tion. Once the job was done, the boatran for years at a perfect trim angle.

Wedges work best when the boat runsat a constant speed. However, mostpowerboats don’t run at a constantspeed, so most people resort to installingtrim tabs. Trim tabs allow the planingattitude to be adjusted while the boatis underway. For example, if the boattrims up by the bow as it transitions ontoa plane, the tab is cranked down a lit-tle more to adjust the trim angle untilthe boat is at its optimum trim attitudefor the speed run. If there is a cross-wind, the tab on one side can be low-ered slightly to compensate for the slightheel that the crosswind creates.

Trim tabs come in a number of dif-ferent sizes depending on the boat size,type and speed capability. Smaller, slow-er boats tend to have wider and shortertabs. The way to get the best size tabfor your boat is to talk to the tab man-

ufacturer. Most tabs are operated bymeans of an electro-hydraulic control.When you press the control switch ortoggle a joystick, an electrical pulse iscreated that causes a hydraulic pumpto turn. This, in turn, causes thehydraulic actuators to raise or lower thetab. I predict that one of the next greatsteps we will see in the electronic/hydraulic control systems is an auto-matically adjusted trim tab. Just dial inthe optimum trim angle for your boatand the tabs will automatically sensethe boat’s attitude and set the tabsaccordingly.

Installing Trim TabsTrim tabs need to be located fairly pre-

cisely. They should be about 3" to 4"(7.6cm to 10cm) inboard from the edgeof the hull chine and around 1/4" to 3/8"(6mm to 9mm) up from the bottom ofthe hull. The farther out the tabs are fromthe hull centerline, the more effectivelythey operate. Before installing tabs, makesure that the outboard turns fully withouthitting them. I installed Bennett (www.bennetttrimtabs.com) trim tabs on mySeaCraft and the manufacturer recom-mends a minimum of 8" (20cm) from tabedge to the motor centerline.

Bennett tab kits contain the hydraulicfluid and everything you need to completethe installation. Installed first is the back-ing plate. Using the backing plate as atemplate, mark the hole locations andcheck the hull inside for any obstructions.(Alternatively, drill a small pilot hole.) Ifyou are drilling into solid fiberglass(uncored), drill the correctly sized hole. Ifyou are drilling into core material, I wouldadvise drilling an oversized hole, filling itwith epoxy resin and then drilling the cor-rect sized hole when the epoxy has set.[Ed: This procedure is known as the pot-ting technique.] This forms a barrierbetween the fastener and the core to pre-

vent water from migrating into the core.All screw holes were touched up with thecountersink bit that makes a small recessin the gelcoat. This prevents splitting ofthe fiberglass and allows caulking to forma small donut that helps to prevent wateringress.

Mounting the actuator to the tab plateis a simple bolt-on job. Install the back-ing plate, tab and hinge plate with theactuator. Now, you have to make somecareful measurements. I found that thebest way to do this is to set a straightedge against the hull bottom running foreand aft. Measure the distance from thestraight edge to the backing plate at thetransom. It should be about 1/4" (6mm)to 3/8" (9mm). Set the aft end of the tabat 5/8" (15mm) to 3/4" (19mm) abovethe straight edge. I found that the easi-est way to get the tab correctly locatedwas to cut a 5/8" (15mm) block and

Long narrow tabs used on high-speedpowerboats.

Measuring placement for tabs.

Correct placement of outboard edge of tab.

Drilling hole for the hydraulic tubing.

After applying a generous bead of caulkingaround drilled holes, actuator is fastened tothe transom.

http://www.bennetttrimtabs.com

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55

position it at the aft end of the tab on thestraight edge. Now, place the actuatoragainst the hull. Bennett recommendsthat you slide the template sheet behindthe actuator mounting and tape it to thehull. I didn’t. I marked the three holes inthe top pad of the actuator and drilledthem out very gently. I hate drilling holesin my boat.

The next job is to drill the center holefor the hydraulic tubing that connectsto the actuator. Bennett recommendsthat you drill a 3/4" (19mm) hole inthe transom and fill it with sealant. Idrilled a 5/16" (8mm) hole first andthen made a 3/4" (19mm) hole deepenough to hold the 7/16" (11mm) lock-ing nut that holds the hydraulic tubingin place. I just didn’t like the idea ofdrilling a 3/4" (19mm) hole all the waythrough the 2" (5cm) thick transom.At this point, I ran the hydraulic tub-ing from the center console to the actu-ator and connected it. All that remainedto do was to screw the actuator to thetransom with the #14 x 1-1/2"(38mm) screws provided. Note thatthe hydraulic tubing cannot be bent at90°. It has to be formed very careful-ly around corners to avoid kinking.

Next, install the hydraulic power unit.It comes with a bracket and all you do

is screw the bracketto the hull or con-sole and slide theunit into the brack-et. You’ll needabout 3" (7.6cm)above the bracketto slide the unit intoit. Place this unit ina dry locationwhere it will not getdrenched or sub-merged. Run theground wire to thenearest groundingpoint and connectthe hydraulic tubingby tightening the1/2" (12mm) nuts.

Use a wrench to torque them up snug-ly. Fill the reservoir with the automo-tive transmission fluid contained in thekit.

Now install the rocker switch bydrilling a 1" (25mm) diameter hole andcutting it square to fit the switch. Itwas wired so that the bow-up andbow-down modes worked properlyaccording to the manual. The final jobis to purge the hydraulics by settingthe tabs to the maximum down angle,

letting them stay down for 15 seconds,then raising them to the maximum upposition for 15 seconds. Once you havedone that a couple of times you shouldhave purged all the air out of the sys-tem. Now refill the fluid level in thereservoir.

That’s it. Put the boat in the waterand enjoy your new tabs. When accel-erating onto a plane, bring the tabsdown a little to help trim the bow downand get the boat on plane faster. Trialand error operation will help you findthe optimum trim angle to get yourboat onto a plane quickly. When run-ning at speed, the only reason to usetabs is to keep the boat’s bow a littlelower so that the trim angle staysaround 4° or 5°. If your boat naturallytrims at that angle, you will not needmuch in the way of tab angle. If youare in a heavy crosswind, lower tab onthat side of the hull and bring the boatback to level.

About the author: When not editing maga-zines, writing books and magazine articlesor designing boats, Roger Marshall findssome time to refit his family’s fleet of boats.

POWERBOAT RIGGING

Locating proper trim tab placement per the Bennett installationmanual.

Always place tabs in the up positionwhen your boat is docked or mooredto prevent barnacle growth on theactuator piston, which would causetabs to jam.

Tip: Tab Docking

Preferred tab location isas far outboard as possible

Minimum 8'' f rom centerline of lower unit

Available tab mounting area

It is okay to mount tabacross lifting strake

Chine

3'' - 4''


56

Story and Photos by Peter Pisciotta

The afternoon sun is low and winds rage asteady 25 knots as a 40-ton, single-enginetrawler squeezes through the breakwaterinto Astoria, Oregon’s east marina basin.Tom and Sue are not new to boating butthey are new to this boat and new to Astoria,having just spent three days at sea. Tomnervously circles and surveys his limitedoptions. The yacht leans noticeably from anespecially angry gust as Sue questions“where are we going to dock?”

“Over there” Tom vaguely says as he pointshis chin over his right shoulder. Sue has noidea what preparations are needed, whatfenders or lines to set. More importantly, Tomis oblivious to Sue’s uncertainty. Unless theydo a better job of communicating, dockingwill be a messy, perhaps damaging maneu-ver, culminating in yelling and hard feelings.

There are two phases of communication:planning and execution (more detail on thisin a later). Planning can be a very short con-versation. I used to command an 85' (26m)dinner charter yacht. When we departed aside-tie, I’d assess the prevailing winds andcurrents, then tell the deck mate what orderto cast-off the dock lines. We had a priorunderstanding that dock lines were num-bered from bow to stern so “one, three, two”meant cast off the bow line first, then thestern line and finally, the midship line. Withonly three words, commands were clear,succinct and actionable.

Communicating 101Set aside time to discuss and prepare your-

self and your crew by finding a safe area topractice. The helmsman’s skill is doublytaxed since “hovering” a boat in windy con-ditions is tricky and novice crews need extratime, so find a safe haven. Too often an ad-

hoc plan is devised enroute when the captainis distracted, leaving the crew no time toclarify and respond, a surefire recipe for aggra-vation.

Instructions should be clear and specific:“We’ll tie-up to the dock abreast of the yellowbox with the bow abreast of the third piling.We’ll need lines and fenders on the starboardside.” Of course, details will vary dependingupon the experience of the skipper and crew(both individually and as a team) but alwayserr on the side of precision. If crew ordersare unclear, speak-up.

Esther and Dennis Bruckel have beencruising the Great Circle Loop for over 10years. They have also crewed on friends’boats, including a trip to Tahiti severalyears ago. “When docking in a new loca-tion, we go around once for a good look,assess wind and currents and formulate aplan,” explained Dennis. “If it doesn’t workout, we retreat and try again with improvedknowledge.”

After a task is completed, crew shouldacknowledge completion in unambiguouslanguage, such as “anchor is free,” for exam-ple. I recently watched a couple back a largetrawler into a slip. The crew was at the sternand totally invisible to the helmsman in thepilothouse. As the swim step approachedthe head of the slip, the crew yelled “good”instead of “stop.” The helmsman interpretedthis as “good, keep doing what you’re doing”and proceeded to crunch the swim step intothe concrete bulkhead, nearly injuring thecrew.

Use terms everyone understands. If thehelmsman can see the crew, approximatingdistance by using outstretched arms slowlycoming together is intuitive but some boatsdon’t allow mutual visibility so verbal cues

are needed. Describing relative distance, like“you’re 10-feet away…” is easy for somepeople but not all. One couple I met used“rugs” as their unit of measure as both couldeasily estimate distance by visualizing a throwrug in their salon.

Mutual AdmirationOnce a maneuver has been planned,

prepared and communicated, it’s time toexecute. Unlike the planning phase, whereone person can do most of the work, exe-cuting is a team effort. There is an inter-esting dynamic with experienced teamswhere vessel control shifts from captain tocrew during maneuvers. Notice how crewactually has control in each of the follow-ing situations.

Casting off lines. The captain is power-less until the crew clears all lines andassures everyone is onboard. Effectively,the crew has control until all lines are clear.

Sail handling, especially in heavy weath-er. The helmsman’s role is to maintain anupwind heading until the sail handler indi-cates completion.

Dropping anchor. As soon as the anchordrops out of the bow roller, the crew is giv-ing instructions to the helmsman on howto handle the boat. Weighing anchor is sim-ilar. Control of the boat does not pass backto the captain until the anchor breaks freeof the bottom.

Docking control becomes dynamic themoment a line is secured to the dock. If abowline is too short, the helmsman has nocontrol. If crew does not properly tie a cleathitch, the boat will drift while the helms-man has assumed the crew has control(tied-up in this case) when the boat is actu-ally underway (adrift).

B O A T H A N D L I N G

SeamlessIntegration Just as a football team huddles before each play, askipper and crew should develop a game plan fordocking or anchoring. Voice activated walkie-talkie

with headset.Anchoring: Crew pointsforward and to starboardindicating the direction thehelmsman needs to go.


57

Maneuvering a boat with springlines(warping) is an age-old practice of “levering”a boat in close quarters. [Ed: Using spring-lines in different docking situations is welldocumented in DIY 2004-#4 issue.] It’sperhaps the highest art form of skipper/crewcommunications because control shiftsdynamically between skipper and crew.

A task driven, time sensitive dialogue takesplace during maneuvers. The crew waits fora specific moment to execute a task, thehelmsman then needs to hold the boat whilethe task is completed. Crisp and clear state-ments signal transition (e.g. “Stern line clear!”)but environmental obstacles like wind noise,engine noise and physical distance can makeconversation impossible. So captain andcrew need to agree upon other communi-cation methods.

Sign LanguageBob and Marie Austin have been cruising

for over 20 years. Bob typically takes thehelm during most maneuvers (though Marieis fully capable). “Communications duringanchoring is purely by hand signals,” saysBob. “Marie looks at the cove as we circlethrough it before dropping anchor and pointsout features, good and bad. Her decision asto anchoring places holds equal weight withmine.” Hand signaling is a great way to com-municate. An arm motioning forward meansgo forward. A raised closed fist means neu-tral, an arm motioning backward means gointo reverse. Whatever signals you devise,make them simple, obvious, and consistentand, most importantly, practice with crew.

Two-way radio communication devicesare a good option, especially popular withcruising couples on large boats. Newerdevices use a voice-activated headset mak-

ing them hands free so you can talk in con-versational tones. I recently worked with twobrothers who each had severe hearing loss.They wore headsets constantly and it reallyenabled them to enjoy their 45' (13.7m)motor yacht.

Role ModelsThe captain usually gets all the glory

but good crew should not be underesti-mated. Ginger Rogers, Fred Astaire’s less-er known dance partner, reminded peo-ple, “I do what he does backwards andin high-heels.” Perhaps the best crewsare also accomplished captains. DaveParker and Linda Lewis were bothaccomplished helmsman when they meteight years ago. When they moved aboarda boat and prepared to go cruising sev-eral years ago, they agreed on almosteverything, except who would be captain.They compromised by trading roles annu-ally. Linda and David became excellentcrew by becoming excellent helmsmen.

Practice and training are importantbecause it takes time to build confidencein each other. Many maneuvers requireprecise timing and crisp execution. Agood helmsman will factor in the crew’sability to perform. For example, securinga line to a dock in adverse conditions(perhaps a strong wind blowing off thedock) requires crew agility and experi-ence. The maneuver may need to bealtered or abandoned unless the helms-man is confident the crew can safely andquickly execute.

Roles change over time so be flexible.Martha and Dave have been boatersmost of the 30 years they have beenmarried. Dave was always at the con-

trols while Martha handled lines. Fortwo years, they planned to cruise theirGrand Banks 42 to the PacificNorthwest when Martha's maneuver-ability was cut short by chronic hip prob-lems. Rather than abandon their cruis-ing dream, they switched roles. Marthahired an instructor to teach her dockingskills and Dave became the line han-dler. It was a difficult transition but even-tually they felt confident in their new roles.

Close quarters maneuvering is a teameffort requiring captain and crew be syn-chronized. Preparation is important,which means prior planning. It takespatience and communication and some-times flexibility.

Back in Astoria, Sue presses for moreinformation. “Tom, ‘over there’ is not aplan. I need more information so I willknow how to set docklines and fenders.”Tom replies, “Okay, you’re right. I’ll makea port turn and land starboard to the endof the dock, right next to the pumpoutstation. In case the wind prevents mefrom turning, it’s possible we’ll end upportside to. Just to be sure, let’s set fullfenders and lines on both sides.” Ten min-utes later, Tom and Sue are admiring thesunset tied up starboard to the dock inAstoria, Oregon.

About the author: Peter Pisciotta is a USCGlicensed 100-ton master, past commercial cap-tain and current owner of SeaSkills PersonalSchool of Seamanship (www.SeaSkills.com).He is a frequent contributor to DIY and lectureson safety and educational topics at WestMarine Trawler Fests, Safety at Sea Seminarsand Strictly Sail Pacific. He has deliveredyachts from Alaska to New Jersey, primarilyalong the rugged Pacific Coast. He can be con-tacted at [email protected].

B O A T H A N D L I N G

Crew brings hand upindicating she is about to askthe boat be put in neutral.

Closed fist: Asking thehelmsman to go into neutral.

10 Tips for BetterCommunications

1. Practice your short game.2. Never yell or even raise your voice.3. Never jump if the boat isn’t close;

retreat and try again.4. Use clear, succinct language.5. Be patient.6. Plan ahead.7. Acknowledge tasks (“Stern line

clear!”).8. Have a contingency plan.9. Be specific.10. Ask questions.

Crew waves back: Askinghelmsman to put the enginein reverse.

http://www.seaskills.com


58

(www.noahsmarine.com), ranges fromCDN$285 for 1/4" (6mm) to CDN$360for 3/4" (19mm). Solid 1" (25mm) squareteak for framing sells for CDN$3.58 perlinear foot (30cm) including millwork. Addthe cost of additional materials, such astools, adhesives and finishing products.

Measure the total area to be covered insquare feet (meters) and make a diagramto determine the number of plywoodsheets and /or solid teak framing materi-al required. Having checked the sole forevenness, determined the plywood thick-ness required and considered the plywoodweight factors, purchase your plywood. Ifyou choose to incorporate teak framing,begin by calculating the number of run-ning feet (meters) required and decide onthe desired width. Have the solid teaklumber ripped to the desired width andplaned to the exact thickness to matchthe plywood/laminate dimension. Reserveleft over teak for making plugs (bungs) tocover the screw heads.

Measuring and Cutting Plywood and framing (if used) are pre-

cut and dry fitted before being gluedand/or screwed to the sub-floor to ensurea perfect end result.

Cut framework pieces first, using mitredcorners, and dry fit them into place aroundthe perimeter. When fitting frames aroundhatches, allow sufficient clearance to raisehatches easily without binding. You needto square the ends before cutting the teakand holly ply. Measure the distance fromthe side edges (long side) to the first avail-able holly strip in several places to makesure the measurements are equal. If theyare not, use a large square and straightedge to square the sheet so the teak andholly strips line up.

With all frame pieces still in place, care-

fully measure the interior area(s) of theframes for the laminated plywood panelsto fit snugly inside. Plan ahead to ensurethat the holly strips align properly withthe adjoining panels. Now, cut the ply-wood panels and dry fit them into place.[Tip: To prevent marring delicate surfaces,such as this plywood, lay duct tape overthe bottom of the saw’s foot. To preventsplintering plywood when cutting, alwaysuse a panel blade, score the cutline onthe finished (top) side with an awl andlay masking tape along the cut line on thebottom — Ed.] Check for sufficient clear-ance at the hatch covers and make anyadjustments necessary to ensure a good fitthat pleases the eye. When all pieces fitproperly, number the back of each panelaccording to your diagram. Apply two orthree coats of epoxy resin to the back andsides of each panel for waterproofing. Youare now ready to fasten them to the sole.

Fastening MethodsIf installing over a fiberglass sole, start

with the perimeter frames (if used) andapply a polyurethane sealant such as 3M4200. Lay a bead close to the undersideedges to affect a solid waterproof seal asthe bead expands out to the edges underpressure. If necessary, apply weights toensure a solid fix. The panels are securedin similar fashion with a bead close to theedges and at 6" (15cm) intervals through-out (across) the back of the panel. Again,weights, such as sandbags or liftingweights, are recommended. (The recom-mended drying time is six hours mini-mum.)

Essentially, the procedure for applyingteak and holly to a wood sub-floor is exact-ly as outlined for a fiberglass sole with oneexception. You must now decide whetheror not to fasten the teak and holly ply tothe wood sub-floor with countersunkscrews and plugs covering the screwheads.The recommended distance between rowsof screws is 6" to 8" (15cm to 20cm)apart. If using this method more for cos-metic reasons rather than to securely affixthe panels, this distance could be increasedfor a pleasing visual effect. With an indeli-ble marker, indicate the pattern of screwholes and plugs in the frames and panelsby creating a grid with strings and drillinga countersink according to the thicknessof the plywood used. This process is notrecommended if you have used 1/4"(6mm) ply. Use black headed screws

By George and Sheilah Van Nostrand

The first step in laying a new cabin sole(floor) is to decide the extent of the areato be covered including stairs, stairwells,locker floors etc. You must also considerwhether you will frame the perimeter ofthese areas and/or the floor hatches withsolid teak lumber strips or apply laminat-ed teak and holly plywood only. The fram-ing method effects the picture perfect thatembellishes the rich appearance of theteak and holly ply. More importantly, itprovides waterproof protection for the endgrain of the plywood when joining piecestogether. A cost-effective option may beto frame the hatches only.

There are three considerations whenchoosing the appropriate thickness: theintegrity of the sub-floor, plywood weightand the cost. If the existing sole is uneven,with low and high spots greater than 1/8"(3mm), a condition easily determined bythe use of an appropriate length straightedge, 1/4" (6mm) plywood may not con-form to the irregularities that will result inan unappealing appearance. A betterchoice is either the 1/2" or 3/4" ply(12mm or 19mm) as it would mask thesole unevenness.

The second consideration is the weightof the plywood being added to the floor-boards (hatches) and, inevitably, the over-all weight added to the boat. A 4' x 8',1/4" (1.2m x 2.4m, 12mm) sheet of teakand holly weighs 23lb (10.4kg). A 1/2"(12mm) sheet of the same dimensionsweighs 47lb (21kg) and 3/4" (19mm)weighs 71lb (32kg). Do the math anddetermine what you’'ll be adding to yourboat’s weight and, just as important, whatadditional weight you are adding to thehatches.

As the weight increases, so does thecost factor. A full sheet of teak and hollyplywood sold by Noahs in Toronto, Ontario

P R O J E C T S

Teak and Holly

FlooringClassic teak and holly wood flooring enriches any boat’s interior. Theluxury appeal of these exotic woods, while enhancing the appear-ance of your craft, requires planning, patience, time and money.

http://www.noahsmarine.com

instead if you wish to add firmly fix this plywood. Next, insert the screws, having first applied a generous

coating of polyurethane sealant to the threads to completethe integrity of waterproofing. Purchase a plug maker equal tothe diameter of countersunk hole and drill enough plugs fromthe spare solid teak frames to complete the job. Apply woodglue to the base of the plug and tap each into place, payingclose attention to orient the grain of each plug so all line up.[Ed: I prefer to set plugs in the same coating (i.e. oil or var-nish) as used to finish the sole.] Let the plugs set for a min-imum of six hours.

Using a sharp chisel slightly larger than the diameter ofthe plug and a wood or rubber mallet, shear off the top ofthe plug about 1/16" (1.5mm) above floor level. Don't cutflush or you risk chipping the plug and having to fill it. Withmedium grit sandpaper on a block of wood, sand the plugflush to the floor. Avoid score marks on the unprotectedteak/holly ply. Be very careful when handling this plywoodas the face (finished side) veneer is very, very thin and easi-ly damaged. Mark and chisel the recess for hatch lifting rings.Installation of these is the very last job.

Finish Coat There are different ways to protect the new sole. You can

seal and protect it with three coats of epoxy resin and then var-nish. This method provides a harder surface and may protectfrom dents inflicted by objects dropped on the floor. If youchoose to go bare, seal the sole with teak oil, though oil tendsto attract dirt and requires routine reapplication. Better yet,apply a semi-gloss interior varnish directly over the bare teak.This requires several thin coats but gives a rich glowing finishthat will charm you and your guests. This method wears welland only requires a light sanding with 400-grit and reapplica-tion of a couple of coats of varnish every few years. [Ed:Alternatively, apply Ultimate Sole, a new product that has gar-





Teak frames, 1" x 5/8" (25mm x 16mm) mounted around the salonperimeter and hatches.

All screw heads are covered with teak plugs. Note that the hollystrips align properly with adjoining panels.

later, the epoxy was sanded with 80-grit paper and then 120grit, followed by a finish wet-sanding over the entire box interi-or with 220 wet/dry paper. Boxes then received two coats ofPettit EasyPoxy (1) with a light sanding with 220 grit paper andcleaning with Interlux 333 (2) between coats. After the paintdried, Cetol refinished fiddles were reattached and a piece ofcarpet cut to fit was laid into the boxes and held in place withLife-Calk (3). Life-Calk was applied to the back side of the coam-ing frame (4) to create a waterproof seal and the box reassem-bled with screws, just hand tightened. Screws were then tight-ened about one and half turns after the caulking had set. Carpet(5) provides padding to protect the surface and cushion thesound when winch handles, flashlights, tools, etc., are tossedin the boxes.

By Peter Caplen

As more and more electronic equipment is installed onboard,the need for clear and unambiguous switch labels becomesmore important. There are a variety of standard switch labelsavailable but quite often they are the wrong size and shape, thewrong style or just totally unintelligible icons.

The solution is to make your own. These can be as profes-sional looking as anything you'll buy and can perfectly matchthe style and color scheme of your boat. They'll also be in astyle that both skipper and crew can understand. All that isneeded is a computer, a printer and a laminating machine


PROJECTS 1

4 5

2

3nered rave reviews from DIY readers. Easy to apply, it seals thewood and provides a glossy finish that isn't slippery when wet.]Now, mount the lifting rings on the hatch boards.

Teak soles are easily maintained with sweeping and washingwith a gentle detergent and water as needed.

About the authors: George van Nostrand is a retired automotive andmarine technician who has owned both wood and fiberglass cruisersfor 36 years. His wife Sheilah, a retired nurse, compliments theircollective restoration and maintainence skills with wood working,fiberglass and painting and varnishing projects on their 1975Tollycraft, “Dream Catcher.”

By Richard Asztalos, “Charisma,” Mt. Clemens, Michigan

My boat's plastic coaming boxes were in bad shape with chipsand dings from flying winch handles and such. As I couldn'tfind any replacements of the same size, I decided to take theboxes out and repair them.

Boxes were first scrubbed clean with dish soap and thenrough sanded with 80-grit paper. Chips and dings were thenfilled with a ready-mix epoxy applied as smoothly as possible. (Iused Marine-Tex but System 3 and others work well.) A day

Like-New Coaming Boxes

Custom Switch Labels

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and, if you don’t haveany of these, you willcertainly know some-one who has.

When I built myboat “Pershilla” in1987, I fitted 30switches on theinstrument panel inanticipation of add-ing equipment overthe years. Whenlaunched, the boathad just 10 switchesin use and now, onlyseven spares remain.Even I, as skipper,was having difficultyremembering thefunctions of some of

these switches and I knew I had to find a solution.After carefully measuring the horizontal distance between

each switch and the vertical spacing available between therows, I designed a simple strip of labels for each row. I useCorel Draw 7 software (6) but any basic drawing program willdo the job. To avoid overcomplicating, I chose bold black let-tering on a plain background, and printed this onto a pale yel-low card that roughly matches the vinyl covering of the instru-ment panel. Card stock makes for a more robust label thanstandard copypaper although, once laminated, this makes lit-tle difference. The printed card was then slipped into a lami-nating pouch and passed through the laminator. If you do nothave access to a laminator, most copy shops will laminate itfor you. Label strips were then carefully cut out using a sharputility knife (7). Cutting the sheet after laminating means thereis no sealed edge around the label and could lead to damp-ness getting into the edges of the card. However, labels I pre-

viously made thisway have lasted forsix years so far. Ifmounting the labelsin an open cockpitor area subject tomoisture, I wouldsuggest cutting thelabels to size andlaminating themindividually to pro-vide a sealed edgearound each one.The finished labelswere then glued

into position (8) using a contact adhesive. Labels for otherareas, such as this fuse compartment (9), are just as easilycreated.

About the author: UK-based Peter Caplen is a mechanical engineerand technical writer with nearly 30 years experience in building,maintaining and renovating mainly powerboats.


6

7

8

9

than on a table (done for photo purposes). Hold up the spliceto check that the strands lie evenly. Lightly tension the strands.

6 Continue tucking, always in the same order: strand two,strand three, then strand one. Each strand passes over the nextstrand on the standing part then tucks under the following one.Always rotate your splice in the same direction (away from

you) when tucking the laststrand (one). Hold up thesplice after each tuck and ifyou make a mistake, undo thestrands and start again. Try toavoid untwisting the fibers.This doesn't affect the strengthof the splice, it's purely an aes-

thetics issue. As you continue tucking, the line becomes tighter,which makes it more difficult to insert the fid. Another reasonfor not pulling tightly on the strands.

7 Mike recommends making five tucks. This follows the ropemanufacturers' recommendations for the number of tucks, albeitmany windlass manufacturers suggest just three tucks. Strengthis not the issue. “Five tucks offers a better transition between thewider chain and splice and thinner anchorline,” explains Mike.

8 Tighten the splice. Don't pull the strands so tight that theline bunches the fibers together. The goal is to apply the sameamount of the tension as on the standing part of the line sothe splice flexes and bends easily.

9 After the fifth tuck, taper the strands to prevent bunching


3 Begin tucking the strands using the common over one,under one, three-strand splice. Start with the middle strand(a). Insert the fid at a 90° angle to the standing part of the line.Be careful not to catch any fibers. Lay the middle strand onthe fid and push both through. Never untwist the line by handto open up the line. Next take the strand closest to you (b) andlay it over the strand you just tucked under and under the nextstrand just below it. Turn the splice over and tuck the last strand

(c) under the one remainingstrand in the standing part. Alltucks will be at the same pointon the standing part. Gentlypull each strand just to takeup the slack.

4 Hold the splice upside down to checkyour work. All strands should all be at thesame height and 120° apart. If two strandswere incorrectly tucked under the samefiber, they would hang side by side.

5 Make the second tuck, passing eachstrand over one, and under the very nextone, starting with strand two (d), thenstrand three, turn the splice and tuck strandone (e). Always select the fiber closest tothe strand. Mike finds it more convenientto work with the chain suspended rather

Easy Rope-to-Chain Splice (Continued from page 7)

A

B C

D E

1 2 3


in the gypsy and to minimize chafe. Take strand three (ignorestrand two) and make one more over one, under one tuck.Now take strand one and make two tucks.

10 Trim off the excess lineusing a hot knife or cut withscissors and burn the endswith a match or lighter. Thisseals the ends to the standingpart so they don't unravel.

When lowering the anchor themomentum and weight of thechain pulls a properly formedsplice through the gypsy. Bynot overtightening the spliceit remains pliable so it flowsfreely around the gypsy, allow-ing a smooth transition fromrope to chain.

You can understand why some boats have deadrise and oth-ers don’t. In general, boats intended for bays and estuaries haveless deadrise than boats intended for operation in high seas andat high speeds. If the sea state and boat speed are known, anoptimum deadrise can be determined for any length of boat.The rub is that most boats don’t operate at a constant speedand in a constant sea state, so a compromise deadrise is used.For production boats that must operate in many different seastates and at variable speeds, deadrise is selected based on theprimary purpose for which the boat is intended. For example,a boat that will putter around a sheltered bay might have adeadrise angle as low as 5° or maybe it will have a flat-bottomif it will almost always operate in smooth water. A typical exam-ple is a clam skiff that usually operates in a sheltered bay earlyin the morning when there is little sea breeze. In contrast, asport fishing boat intended to go offshore and operate at speedsto about 30 knots might have a deadrise of 12° to 16°, where-as a high-speed powerboat operating at speeds of up to 80 mph(129 km-h) might have a deadrise angle of up to 22° to 24°.

About the author: Roger Marshall is a boat designer and author of12 books on sailing and yacht design. He has a boat design compa-ny in Rhode Island and is the president of Boating WritersInternational.

View from thethe SternnS(Continued from page 64)


64

In pre-plywood days almost every boatwas built with a rounded bottom and theseslower powerboats tended to give a smoothride. Of course, in those days, enginesweren’t very powerful and hull shapes usu-ally had gently curved lines to allow theboats to go through the water withoutharsh pounding. As technology changed,so boat designed changed to accommo-date it. High powered engines drove boatsfaster and the hulls could plane, skimmingover the water, provided that the hull wasshaped properly for planing. As the con-cept of planing became better understoodand its benefits were sought, boats becamewider.

To get a feel for why wider is better whenit comes to planing, think of an airplanewing. The wider the wingspan, the greaterthe lift that is obtained and the easier it isfor the airplane to fly. Similarly, the greaterthe beam of a hull, the easier it is for aboat to get on a plane. As boat bottomsbecame wider, they also became flatterlongitudinally, which also made it achievethe planing effect. However, a wide, flat-bottomed boat tends to pound the waterinstead of slipping through it, so the con-cept of deadrise came into being. Deadriseis the angle from horizontal to the hull orthe angle in which the hull rises from thekeel to chine. The measurement is usual-ly taken at the transom for convenience.However, as a design guide, designers usedeadrise at various stations on the linesplan. These stations cannot be found ona finished hull without very careful meas-urement. Some say deadrise was firstdeveloped by Ray Hunt back in the late1950s but there is enough evidence tosuggest that deadrise was around longbefore then. What Hunt did was to incor-porate longitudinal strakes on his “Moppie”designs to provide additional lift and getthe boat on a plane earlier.

In general, a deep deadrise gives a soft-er ride than low deadrise. Think of a knifegoing through butter. If you use the sharpedge of the knife, it slides through the but-ter easily. If you use the flat side of theknife, it mashes the butter outwards. If,instead of a knife you used a wedge, you’dfind that the wedge would go only so farinto the butter until its width stopped itfrom going farther. By adjusting the angleon the wedge, you could adjust how farit went into the butter. Deadrise on a boatis rather like a wedge pushed into butterin that it goes only so far into the waterbefore its width stops it. If you add chinestrakes, the impact is a little harder andit stops faster.

So now let’s consider different degreesof deadrise. A flat-bottomed boat mash-es the water flat, spreading it out to thesides and giving a jarring ride. A boat witha moderate deadrise (“vee”) moderatesthe ride, reducing the pounding motionor the sensation of slamming into thewater. A boat with a very deep vee goesa long way into the water but eventuallythe reserve of buoyancy in the upper partof the hull stops it (you hope!).

Which type of bottom is best dependspartly on the conditions to be encoun-tered. If you design a flat-bottomed boat,it will skim across the water generating

maximum lift but as soon as it encoun-ters a wave, it will slam down hard andmust either slow down or inflict a painful,possibly damaging, blow to the boat orthe crew. This says that flat-bottomedboats are best used where they are unlike-ly to encounter waves or heavy seas. Avee hull, on the other hand, can absorbwave impacts as it sinks into a wave, soit will work well in a seaway. As the boatgoes faster, so it needs to sink farther intothe waves to recover from the impact.Therefore, a good designer will give a high-speed boat more deadrise to absorb theheavier impacts. Simple isn’t it?

Now that we have laid down thesebasics, let’s turn to another problem. Aboat with a high deadrise is not flat-bot-tomed enough to generate sufficient liftto get it on a plane quickly. It takes a longtime to haul its transom out of the water.Quite frankly, that’s not good enough formost powerboaters, so designers useanother neat trick. They put strakes alongthe hull to generate lift. These strakesaren’t wide enough to cause problemswhen the boat impacts the water. By plac-ing them strategically along the length ofthe hull, each strake works to get the boaton plane. Then, as the boat rises onto theplane, each strake lifts out of the waterand its resistance disappears. So ulti-mately, at full speed, the boat is riding onjust the lower strake and the bottom ofthe hull. You can now begin to see howclever designers are. Using lots of strakeshelps to get a boat onto a plane and oncethe strakes are out of the water, their dragis eliminated and the hull is able to planeeasily. To increase lift when the boat isrunning at full speed, some designers puta flat pad at the back end of the hull. Thisgives the benefits of a flat-bottomed boatalong with all the benefits of a deep-veehull. Pretty smart, huh?

View from thethe SternnSWill that be

Hard or Soft? Deadrise, measured in degrees, determines a boat’s ride characteristics. Some boats ride hard, others

give a softer ride. Which type of bottom is best depends largely on where you go boating.By Roger Marshall

Stern shapes determine ride, handling andperformance.

DEEP-VMODIFIED-VROUND

BASE LINE

(Continues on page 63)

40 ELECTRONICS - Whitsunday Discount Marine...10 DIY TECHNICAL HELPLINE — It’s FREE Technical...

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