[s-cars] Pressure Test

Djdawson2 at aol.com Djdawson2 at aol.com
Sun Apr 27 23:40:31 EDT 2003

[ Picked text/plain from multipart/alternative ]
Regarding pressure testing....  You don't "need" to block off anything.  You
do need a sufficient, regulated supply of air.  You will be pressurizing your
crankcase, and as a result, may hear slight pressure leak noise at the oil
cap and/or dipstick tube.  Yes, air will pass by valves (exhaust only) that
are partially, or fully open, allowing some air pressure to go out the
tailpipe.  But the noise made by this is nearly inaudible under the hood.
Open intake valves don't allow air to go anywhere, except past your rings,
which contributed to crankcase pressurization.  I've never encountered an
overlap situation.

I have done this on many Audis, and it works very well.  Most recently with
Hap, and he can certainly attest to its effectiveness.  We blocked nothing
off, and the crank position was simply as it shut off... we didn't try and
insure that valves were closed.  I think the biggest problem you are having
is a lack of air volume sufficient to cover the losses that occur during this
type of test.  My compressor has a 60 gallon tank, and we regulated it down
to about 15 psi, so volume wasn't an issue.  Readings should appear at the
regulated pressure on any gauge you have installed.

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