Paul wrote,
>
>What is the concern with the thrust washers? How big a job is it to
>it/them? Is the 'falling RPM' test a definitive test, or should I
>perform=20
>other tests before wading in here? How long will the engine continue
>with=20
>the worn washers, and what is the failure mode?
>May I suggest this phenomenon be added to the 'Alpine buyer's guide'
>on the=20=
>SOL web server - Daniel Levitin was the author of that page. Are you
>still=20
>with us, Daniel?
>Thanks again for your help, people. I guess I really need to find
>that=20
>Practical Classics article on the 1592 rebuild now...
>Cheers,
>Paul.
If the motor has good oil pressure and compression, dont rebuild it.
I dont think that there is a definative test here for the thrust washer
prob.
Many of us have seen the problem just go away after a quality rebuild.
The rest is probably well seasoned folklore.
Some of the time, worn thrust washers will show a marked reduction in oil
pressure when the clutch is pressed, but the drop in RPM probably has
more to
do with the wear state of the TO bearing, and the type of clutch than
anything else.
The TO bearings can be worn clear down to the metal backing without
making
a noise. The friction that the iron carrier imparts on the clutch is
somewhat higher
than that of the graphite ring, so this is also a possibility.
Knowing when the clutch should be pressed, and for how long to press it
is really
important toward making the carbon TO bearing, and the thrust washers
last a long
time. Clutching is the only significant force that the the thrust
washers ever see
"anyone out there with an automatic have a thrust washer failure?".
You should NEVER start an alpine with the clutch pushed in.
The engine has NO oil pressure, so the crank is hard up against the
thrust washers,
and there is definately metal to metal.
The good news is that the thrust washers can be checked and replaced
without
pulling the engine of even the crank from the car.
The whole affair is probably a six pack job, so buy 9 just in case.
You will have to drop the sump, pull the center main cap, then use a
feeler
gauge to measure the end float of the crank. You will have to push the
clutch to
be certain that the crank is butted against the thrust washer on the
tranny side of
the engine. Measure the end float between the crank and the thrust
washer
toward the front of the engine.
If the end float is greater than .004 inches, you ought to replace them.
After the end float has been measured, slide "rotate" the old thrust
washers out
of the crescent recesses in the engine block. Measure each one for
refference.
New thrust washers are available with .005 and .010 oversize. You can
also
mix your warn pieces with new pieces or you can machine down the
backsides
of the new washers to get that "just right" fit.
The correct end float wil be .002 to .004 inch.
Remmember that the copper/grooved sides go against the crank, and the
white
metalic side goes against the block.
Later,
Jarrid Gross.
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