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Re: Valve noise
firstname.lastname@example.org (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
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