Re: quattro-digest V3 #1014

[baselope@netwide.net (Robert Riley)]

>Conventional wisdom on the list is that the valve noise you describe can
>be solved by switching to a *good* synthetic motor oil, such as Mobil 1
>or Red Line. Problem is immediately after starting, oil pressure builds
>slowly enough that hydraulic lifters don't get a full load of oil right
>away. Dino oil eventually gets fluid enough and pressurized enough to
>make it to the lifters, and the noise stops. Synth oil flows better
>cold, so the noise stops sooner. HTH.

This is one possible solution, certainly the cheapest.  I have a source 
to purchase the lifters for $11 each, so I tried replacing all of them.  
Guess what, I still had the same problem.  It turns out that the noise 
was actually being made by the Vacuum Pump on the side of the head.  I 
live in Florida, (below 1000 ft above sea level) so I did the easy thing. 
 I removed the push rod in the pump.  Noise is 100% cured.  For your 
notes, I tried just replacing the pushrod on suggestion from another 
mechanic, but the pump is the true problem.

Appearantly the pump can get oil in th air passage and this over time can 
cause the problem.
The pump is not neccessary if you live in low lying areas (below 1000 
feet), but is required for mountains or higher ground.


Justin Riley
1987 Coupe GT  156,000 miles and counting.
1988 Audi 80 (4 cyl) 263,000 miles and purring!