SEL-29-01

SingleEngine SERVICE LETTER

SEL-29-01TITLE

HYDRAULIC POWER - HYDRAULIC POWER PACK INSPECTION

EFFECTIVITY

MODEL SERIAL NUMBERS172RG 172RG0001 thru 172RG1191

R182 & TR182 R18200584 thru R18202039210 & T210 21062955 thru 21065009

P210 P21000151 thru P21000874FR182 FR18200021 thru FR18200070

REASON

Cessna has received a report of possible electrical arcing at the positive terminal connection on thehydraulic power pack motor for the landing gear.

DESCRIPTION

This service letter provides instructions to do an inspection of the hydraulic power pack wiring for correctinstallation.

COMPLIANCE

MANDATORY. This service letter must be accomplished at the next scheduled 100 hour/12 month(annual) type inspection.

REFERENCES

Applicable Cessna Airplane Service/Maintenance Manuals, Wiring Diagram Manuals, and IllustratedParts Catalogs. Refer to www.cessnasupport.com.

ACCOMPLISHMENT INSTRUCTIONS

1. Prepare the airplane for maintenance.

A. Make sure that the airplane is electrically grounded.B. Make sure that all switches are in the OFF/NORM position.C. Disconnect electrical power from the airplane.

(1) Disconnect the airplane battery.(2) Disconnect external electrical power.

D. Attach maintenance warning tags to the battery and external power receptacle that have "DO NOTCONNECT ELECTRICAL POWER - MAINTENANCE IN PROGRESS" written on them.

2. Get access to the hydraulic power pack for the landing gear. (Refer to the applicable service/maintenancemanual.)

SEL-29-01July 16, 2012 Page 1 of 6

Cessna Aircraft Company, Cessna Customer Service, P.O. Box 7706, Wichita, KS 67277, U.S.A. 1-316-517-5800, Fax 1-316-517-7271,Email: [email protected]

This document contains technical data and is subject to U.S. export regulations. This information has been exported from the United Statesin accordance with export administration regulations. Diversion contrary to U.S. law is prohibited. ECCN: 9E991

COPYRIGHT 2012

SEL-29-01Page 2 July 16, 2012


SEL-29-013. (Refer to Figure 1, Detail A and Detail B.) Do an inspection of the installation of the power lead and

suppression diode connections to the hydraulic power pack as follows:A. Look at the positive terminal to see if there is evidence that arcing has occurred.

(1) If you see no evidence that arcing has occurred, go to Step 3.B.(2) If you see evidence that arcing has occurred, repair or replace all damaged components.

Then go to Step 3.B. (Refer to the applicable service/maintenance manual, wiring diagrammanual, and illustrated parts catalog.)

B. Look at the wiring for condition and installation as follows: (Refer to the applicableservice/maintenance manual, wiring diagram manual, and illustrated parts catalog.) Look to see if the routing of the power wire and diode's negative lead are oriented up and away

from the case in accordance with best practices, applicable service/maintenance manual, andapplicable wiring diagram manual.

Make sure that the power lead and diode's negative lead are secured between the two positiveterminal nuts so that the bottom nut acts as a spacer and that under the bottom nut is aninsulating washer.

Make sure that the power lead and diode's negative lead ring terminals at the positive terminalare not bent toward the case of the power pack.

(1) If the wiring is in serviceable condition and the routing of the power wiring and diode is donecorrectly, go to Step 3.C.

(2) If the wiring is not in serviceable condition and/or the routing of the power wiring and/or diodelead is not done correctly, do as follows: (Refer to the applicable service/maintenance manual,wiring diagram manual, and illustrated parts catalog.)NOTE: In some installations, the two case bolts may be safety wired.(a) Repair/replace the wiring and/or do the routing of the wiring again as necessary until it is

in accordance with best practices and the applicable service/maintenance manual andwiring diagram manual, as described in Step 3.B.

(b) Make sure that the attachment hardware for the 1270717-2 Diode Assembly is installedexactly as shown in Figure 1.

(c) Make sure that the 1270717-2 Diode Assembly is installed with the marking band(negative lead) on the diode facing toward the positive terminal.

(d) Use MS3367-1-9 Tie Straps as necessary to securely attach wires to make sure that thepower lead and diode assembly wires do not touch the case of the power pack.

(e) If you must remove the attachment hardware for the 1270717-2 Diode Assembly, asyou install it again make sure that the nut closest to the power pack is snug againstthe insulating washer. Tighten this nut with your hand and then, with a wrench on thenut, tighten the nut a quarter turn more.

(f) If you must torque a nut on the power pack, use a backup wrench on the nut adjacent tothe insulators to make sure that no stress is put on the insulators and that none of thetorque is transferred to the terminal posts.

C. Look to see if an A-A59178-3 Nipple is in serviceable condition, installed over the wiring at thepositive terminal, and securely attached in position as necessary with tie strap(s). Make sure thatthe nipple covers both the diode wire and the power terminal wire.(1) If an A-A59178-3 Nipple is in serviceable condition and is securely installed over the wiring at

the terminal, go to Step 4.(2) If a nipple is installed over the wiring at the terminal and the nipple is deteriorated or damaged,

discard the nipple, trim the end of the new A-A59178-3 Nipple where the wires come out ifnecessary, install the new A-A59178-3 Nipple, and attach it securely in place with tie strapsas necessary. Then go to Step 4.


SEL-29-01(3) If no A-A59178-3 Nipple is installed over the wiring at the terminal, trim the end of the new

A-A59178-3 Nipple where the wires come out if necessary, install the new A-A59178-3 Nipple,and attach it securely in place with tie straps as necessary. Then go to Step 4.

4. Connect the airplane battery.5. Do a general inspection of the power pack installation for secure attachment, correct installation, and

hydraulic leaks.6. If you removed or replaced wiring or components, or corrected the routing of the wires for the power pack,

do a functional test of the retractable landing gear operation. (Refer to the applicable Service/MaintenanceManual.)

7. Install components that you removed to get access to the hydraulic power pack. (Refer to the applicableservice/maintenance manual.)

8. Remove the maintenance warning tags.9. Make an entry in the airplane logbook that states compliance and method of compliance with this service

letter.

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SEL-29-01

Figure 1. Hydraulic Power Pack Inspection (Sheet 1)


SEL-29-01

Figure 1. Hydraulic Power Pack Inspection (Sheet 2)

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SEL-29-01

MATERIAL INFORMATIONThe parts below may be necessary and are available from Cessna Service Parts and Programs throughan appropriate Cessna Authorized Service Facility.

NEW P/N QUANTITY KEY WORD OLDP/N

INSTRUCTIONS/DISPOSITION

A-A59178-3 1 Nipple Various Discard (If necessary)MS3367-1-9 As required Tie Strap Various

MS35338-44 1 Lock Washer Various

MS35650-3252 2 Nut Various

NAS1149F0416P 2 Flat Washer Various

S1438-17 1 Insulating Washer Various

1270717-2 1 Diode Assembly Various

SingleEngine OWNER ADVISORY

SEL-29-01TITLEHYDRAULIC POWER - HYDRAULIC POWER PACK INSPECTION

TO:Cessna 172RG, R182, TR182, 210, T210, P210, and FR182 Owners

REASONThis owner advisory is to inform you that SEL-29-01 has been issued.

Cessna has received a report of possible electrical arcing at the positive terminal connection on thehydraulic power pack motor for the landing gear.

SEL-29-01 provides instructions to do an inspection of the hydraulic power pack wiring for correctinstallation.

COMPLIANCEMANDATORY. This service letter must be accomplished at the next scheduled 100 hour/12 month(annual) type inspection.

LABOR HOURSApproximately 0.7 man-hour to accomplish this service letter

WARRANTYNot applicable

Please contact a Cessna Single-Engine Authorized Service Facility for detailed information and arrangeto have Cessna Service Letter SEL-29-01 accomplished on your airplane.

NOTE: As a convenience, service documents are now available online to all our customers through asimple, free-of-charge registration process. If you would like to sign up, please visit the "CustomerAccess" link at www.cessnasupport.com to register.

SEL-29-01July 14, 2012 Page 1 of 1

Cessna Aircraft Company, Cessna Customer Service, P.O. Box 7706, Wichita, KS 67277, U.S.A. 1-316-517-5800, Fax 1-316-517-7271,Email: [email protected]

This document contains technical data and is subject to U.S. export regulations. This information has been exported from the United Statesin accordance with export administration regulations. Diversion contrary to U.S. law is prohibited. ECCN: 9E991

COPYRIGHT 2012

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