8/10/2019 Ajustar Vlvulas VW

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COST:

Approx 2

TIME TAKEN:

1/2 hour - 1 hour

DIFFICULTY:

@@TOOLS USED:

flat blade screwdriver, 13and 21mm spanners, feeler

gauges, Tippex

Toptip

2 8 KYLA

AdjustingtappetsTHERES NOT MUCH that needs regular adjustment on a VW engine,

but the valve clearances do. Its easy once you know how

A

djusting thetappets on anyair-cooled VWis a relatively

straightforward procedure,but its one that many peopleeither fear or simply dontbother doing. Once youvegot your head around theprocess though, youll fndit comes as second nature.Remember though, it mustonly ever be done with theengine stone cold, so if youvedriven your car that day, leave ituntil tomorrow to do this job.

Weve only shown half theprocess here as its exactly thesame for the other two cylinders

on the other side of the engine,just remember to turn the engine180-degrees anti-clockwisebetween each cylinder.

Just so you know what youredealing with, the tappets arethe parts that operate the inlet

and exhaust valves and allowa carefully calculated amountof valve lift. Hence why youllalso hear this job referred to as

setting your valve clearances.On a stock engine they shouldbe checked regularly and set to

the factory settings every 3000miles for optimum performanceas if the tappet gap is allowedto stretch, valve lift will be

decreased and performance

will suffer. Plus your enginewill sound like a bucketof nails being rattled.Alternatively, if the tappetgap closes, the valve will belifted off its seat, which willsoon damage the valve andvalve seats. In short, keep

on top of tappet adjustment andyour Beetle will run happilyever after (hopefully).

This clever tool called aClickadjust is available from FrostAuto Restoration Techniques(see www.frost.co.uk) and makesdoing this job a doddle

Never be tempted to re-use oldrocker cover gaskets, buy twonew ones before you start the job

Once youve found the TDCnotch on the pulley clearly markit with Tippex, then mark it at180-degrees from there as well

Youll also hear thisjob referred to assetting your valve

clearances

TAPPETCLEARANCESAccording to VW, pre-1971air-cooled engines shouldrun 0.004-inch clearance, with the engine stone cold.

Post-1971engines should be set to 0.006-inch.

Heres what youll f ind underyour rocker covers. And yes,it should be covered in athin film of oil like this

H O W T O A D J U S T I N G T A P P E T S

8/10/2019 Ajustar Vlvulas VW

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Q: Can I use a

cigarette paper or somecard to set my tappets?

A: No, you tight-fisted git ,buy some feeler gauges

and do the job right!

Q: How oftenshould I check the tappets?

A: Ever y 3000 miles, so whynot do it each time youchange your engine oil?

KYLA

2 9

01 Pop off the dizzy cap, then rotate the engine by the top pulley nut untilno.1 piston is at TDC. This is when the rotor arm lines up with the notchin the body of the dizzy and when the notch in the lower pulley lines up with thecentreline of the crankcase (see close up pic of pulley on the opposite page)

05 If thegap isincorrect, loosenthe 13mm lock nutand adjust the valvegap by screwingthe adjuster eitherin or out . Hereswhere the thirdhand comes inhandy as you needto check the valve

clearance with thefeeler gauge whileyou re-tighten thenut. Do both theinlet and exhaustvalve on no.1 in thesame way

06Once yourehappy withboth valve clearances onno.1 piston, rotate thecrankshaft anti-clockwiseby 180 degrees, untilthat second mark youmade on the pulley (seetop tip) lines up with the

crankcase centreline

08With the tappets on pistons no.1 and 2 adjusted, clean your rocker coverand fit a new gasket. If you have any trouble keeping it in place whileyou re-fit the cover, try a couple of small blobs of Vaseline or similar

02Now remove the rocker cover for no.1 and 2 pistons (the right handside looking into the engine bay) by prying the spring clip down with ascrewdriver or pry bar

03 Be preparedfor a smallamount of oil totrickle out of thecover and cylinderhead. Try not to letit drip all over theexhaust below

04No 1cylinderis to be checkedfirst that s theone on the righthand bank nearestthe flywheel. Feelfor movementby hand first andthen insert thefeeler gauge andcheck for furthermovement.

[NB Youll notehere that theseare bolt-up rockershafts, just to showyou the processdoesnt vary]

07Returning to the same side underneath the car, you now have to repeat

the process on the no.2 valves the two nearest the crank pulley end

ENGINE

H O W T O A D J U S T I N G T A P P E T S