On Thu, 23 Feb 1995, Greg Schulz wrote:

> Mike Catlin ;
> 
> Looks like you have a fair amount of experience with diesel 
> Vanagon's.  Mine runs at what I feel is on the high end of safe on the 
> temperature gauge.  I posted the following on rec.auto.vws a few 
> days ago, no answer yet, do you have any thoughts on this?

Greg, my diesel has been not running for so long that I can't remember 
exactly where the guage reads while cruising on the flat.  I assume that 
somewhere between those two middle marks is fine.  In hot weather, I 
recall the guage reading one or two needle widths more toward hot on the 
scale.  While climbing a grade in 100 degree F weather and floored in 
third at 42 mph for 20 minutes or more, the guage will reach the bottom 
of the red zone.  Upon descent or stopping to idle the guage returns 
rapidly to normal.

> 
> My 1984 Vanagon diesel temperature gauge goes to about 3/4 over 
> to high when driving.  Even on cold Iowa mornings, -10 degrees.

If that's half way between the upper normal mark and the bottom of the 
red zone, while driving 55 to 64 (my top speed) on the flat, then I think 
it's too high.  I'm not sure if you and I have the same guage face, though.
  
> When I idle for an extended time at 50+ degrees I read just under 
> high.  Is this normal? 

I don't think so.  Mine used to be able to idle for a long time without 
heating up.  When idling in traffic it would usually cool down a little.

 The front cooling fans are running after the 
> temp gauge is about 1/2 way to high.
> 

This is normal.

A complete cooling system checkout would be a good idea.  There could be 
blocked tubes in the radiator.  Some aftermarket water pumps develop a 
loose impeller.  The wrong type thermostat could be fitted.  The correct 
one has an air vent hole and also when it opens it will block the bypass 
circuit, while a wrong type that happens to fit might not work.  Then 
there is the big problem with diesels.  You could have a combustion leak, 
where, under load, gases leak around the head gasket or sometimes through 
a crack.  The resulting hot bubbles severely reduce the effectiveness of 
your cooling system.  I don't mean to scare you, it's just that these are 
some possibilities you need to eliminate.

> PS
> My Vanagon has 114,000 miles on it.  I bought last summer, sight 
> unseen.  I have replaced the starter, timing belt, and all the filters.  
> Everything seems fine, one of CV joints was replaced at about 
> 100,000 and something on the head was work on but the previous 
> owner did not know what.  Is there anything else to look for to fail?
> Thanks for any help this.
> 
> Greg Schulz e-mail gschulz@squeaky.free.org  
> 
> 
 Anything else to fail?  Yes, those three seals on the pulley side of the
engine are due to start leaking, and the VW replacements are a superior
product.  If you ever have the head off, get it measured for straightness
and use high performance studs and nuts instead of the VW stretch bolts. 

Anyone else out there have ideas?

Good luck, Greg.

Mike <mjcatlin@wheel.dcn.davis.ca.us>