hertz audis

[QSHIPQ@aol.com]

Phil writes:
> > I'm not a good enough mechanic to do that myself, but my mechanic is te>
lling me
> > that the marks on my flywheel are at the wrong place.
>
> ???? Never heard of such a case.

>>Neither have I.

>>However, it's pretty easy to check.  The flywheel mark corresponds to
>>TDC on cylinder #1.  Just whip out the plug, drop a stick down the hole,
>>and move the flywheel around either side of the mark.  If you get a
>>friend to sight over the top of the stick at a distant target, you'll
>>be _AMAZED_ at how sensitive the technique is.  With practice, you can
>>get the flywheel mark +/- 5mm - enough to verify that it's roughly
>>correct.

>>And if it's roughly correct, odds are it's _exactly_ correct.

Sometimes.  There is a huge production tolerance in the TDC of audis.  In
fact, if you ever do any engine work, you owe it to yourself to ck the
accuracy of TDC.  I and several other folks have found that the "exactly"
correct is more like not exactly, just kinda roughly.  A couple degrees either
side of TDC has been found by many, I have measured no more than 2, but that's
plenty to create quite a difference in motor output.  Remember, you have
machines that need to punch 8 holes in the flywheel, mount 1 pin, and whack
one "O", all with the same #1 cyl TDC reference point.  "Exactly" is a pretty
big assumption, considering all flywheels mark the same regardless of engine
(specifically crank) tolerances.  Check around at the shops that do the motor
work, you might be somewhat surprised.

My .02

Scott Justusson