Date:         Wed, 15 Feb 95 11:21:09 PST
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         wall@orangeu.mcm.com (Steve Wall)
Subject:      Cooling system drivel (long, sorry)


Cassie ('89 Westy GL, 101k miles, head gaskets replaced at 81k miles)
has a cooling problem whereby she runs a bit hot (according to the
temp sensor, which, I assume is accurate...). Blue Goo coolant has to be
added once a week (just a top off, no huge leaks).

I've been told by VW dealer #1 that I need:

	Thermostat
	Water pump
	Radiator

	$930.00

and by VW dealer #2 that I need:

	Radiator

	$530.00

In order to educate myself about my new pal Cassie, I've invested in
the Bentley book, and it was useful in understanding the cooling system.
The questions now are, am I smart enough to 1) diagnose the problem in
more detail and/or 2) do some/all of the work myself?

Diagnosis of Water Pump:

	I have no signs that the water pump needs replacement.  The system IS
	cooling, just not at peak efficiency. If the water pump is
	out/flakey, then I'd think I'd have SIGNIFICANT cooling
	problems.

	Diagnosis: I don't really need a water pump at this time,
	although it might be a good precautionary move.

Diagnosis of Thermostat:

	The thermostat seems to be operating ok - opens at 85 degrees C,
	no heat in the heating system until it opens, etc. There IS a 
	white residue around the thermostat housing, but no obvious
	leaks.

	Diagnosis: I don't really need a thermostat at this time.

Diagnosis of Radiator:

	Since all other parts of the system seem to be operating well,
	it'd seem that the radiator is having trouble cooling well. It
	could be corroded (non-VW Blue Goo used by prior owner?),
	leaking (no visible signs, however...), or something.

	When Cassie is in motion, the radiator fan never comes on (it
	does when running hard and then we sit at idle [makes sense]),
	so the radiator is doing some cooling, just not sufficient to
	keep the temp sensor at or below midpoint. The fan sensor
	seems to switch on at the right time, etc.

	Diagnosis: Radiator should be replaced, probably is corroded
	inside which keeps it from allowing enough coolant flow to pass
	through, raising the overall temp of the coolant in the entire
	system. Could also have a leak which is where coolant is
	leaking, thus the need to top off weekly (wouldn't this
	introduce air into the system?). Could rod out the existing
	radiator as David Garth did on his '86 if it was corroded
	but not leaking.

So, if it's the radiator, can I replace it myself?

	VW sells a radiator fo $420. Other parts stores sell OEM
	for $275. I'd probably buy the OEM - is this safe?

	The drop, install, refill coolant appears to be pretty
	straightforward according to Bentley - anybody ever done
	this - if so, any warnings?

Thanks for the feedback - sorry this is so long, but when you're just
learning about this stuff, you tend to go on like this....

Steve

-------------------------------------
Steve Wall (wall@mcm.com)
Mellon Capital Management Corporation
San Francisco, CA