overheating 4000q

[Bruce Bell]

Hmmm. this is a bit perplexing....I'd hate for you to lose another head
gasket. your Bentley seems a different edition from mine as I have neither
of your page references. Mine says 8 degrees (+-2) initial advance and shows
a total max advance of 21-26 centrifugal and 10-14 vacuum. I guess that
would be a total of max 40 degrees at 5500 rpm according to my edition
(earlier I suspect). Certainly your 6 degrees advance is not a problem.

You did describe the color of your spark plugs as having "smallish amount of
light gray deposits" and while descriptions like this are somewhat
subjective, I prefer a color not unlike that of a 4-6 shot Latte (easy on
the milk please). Classically referred to as a slightly chocolate color. If
all your plugs are about the same color I'd be inclined to dismiss any head
or current gasket problems Do you have a duty cycle meter? Go to section 25
and run through the part on CO value duty cycle checking/adjusting. Your
description of the plugs color makes me think lean. And that generates
excess heat in the head. I'm not sure where else to look since it appears
you left no stone unturned on the cooling system side.

Bruce\
-----Original Message-----
From: George Nimmer [mailto:george164 at earthlink.net]
Sent: Wednesday, September 11, 2002 5:44 PM
To: bbell at surview.com
Cc: quattro at audifans.com
Subject: RE: overheating 4000q


I checked the timing today, and it's at about 6 degrees @ idle (Bentley
says it should be 6 degrees + or - 2), and at about 40 degrees @ 3500
rpm.

My Bentley manual says to look on page 28.40, however 28.37 is the last
page in the ignition chapter!  Guess my book has a printing error?

Any idea how I reduce the amount of advance?

Thanks