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Re: Valve noise

jrd@po.cwru.edu (John R. Daker):
>I have an 86 4000CSQ.  When started, it makes a bunch of noise.  SOunds
>like valve clatter.  Problem:  They're hydrauli and non-adjustable.
>So, the problem must lie elsewhere.  It does quit after the engine has
>run for a while.   Any of you geniuses know what this is?  WHat should
>be done?

This is a fact of life with these engines as far as I can tell.
Speaking only from memory, I believe the book says to rev a warm
(radiator fan has cycled) engine at 2500 rpm for two minutes.  If
lifters don't quiet down, then replace lifters. I have an 84 with
over 200,000 miles that has always been a loud clacker on startup,
but generally passes the test.  Else a treatment of Rislone or MMO
will quiet them in minutes.  Same with the 86 @ 120,000.

It might even be worth speculating that Audi was pursuing a design
goal in making the lifters weak, intended for Autobahn and all that,
but they supplied solid lifters outside the U.S., so maybe a little
less overlap at low rpms help emmissions.  Maybe they just botched
it, as with the exhaust manifold/gasket situation.  Nonetheless
they do work as advertised when held to the specification supplied.

>Yes, I have come to the realization that I need the Bentley book, but
>can't afford the admission price yet.  Besides, what could a book tell me
>that you guys (and gals) couldn't?

As a how-to book I'd rate the Hanyes much higher than the Bentley.
Although it doesn't cover the quattros I wouldn't say it matters.
In fact, if I recall correctly the Bentley doesn't have a section
for the quattro transmission itself. 

Eliot W. Dudley                       
3388 State Rt 370  
Cato, New York  13033
315 626 2878