Date: Mon, 15 Sep 1997 03:32:10 UT
Reply-To: Dennis Haynes <dhaynes57@CLASSIC.MSN.COM>
Sender: Vanagon mailing list <Vanagon@Gerry.SDSC.EDU>
From: Dennis Haynes <dhaynes57@CLASSIC.MSN.COM>
Subject: Re: '87 Vanagon Thermostat?
You need to check the following:
* Pressure cap, make sure the valve is not blown out and that it can maintain
set pressure. Just replace it, cheap insurance. Also make sure the cooling
system is properly filled and bleed. Must also have proper mixture. Straight
water or antifreeze is no good.
* Internal cylinder head leaks. Combustion gasses getting into the cooling
system will vapor lock the pump keeping water from flowing. Have a leak down
test performed. Also check that the heat always works. Intermittent heat is
the first sign of this problem.
* Blocked radiator. Keeps water from flowing when t-stat fully opens. I
doubt this but check any way.
* Cracked radiator baffle. This is a good one. Radiator has to be removed so
you can look inside. If the separator cracks, water can enter and leave the
radiator with out actually flowing through. This will cause all sorts of
weirdness. Overheating after highway run is most obvious. At high engine
speed, the pump moves enough water so that the radiator can still provide some
cooling. Back at idle, most of the water that flows bypasses the radiator and
the switch to turn on the cooling fan. This will result in an overheated
engine if left unchecked.
Hope this helps,
Dennis
-----Original Message-----
From: Vanagon mailing list On Behalf Of Brendan Irwin
Sent: Friday, September 12, 1997 6:31 AM
To: Vanagon@GERRY.SDSC.EDU
Subject: '87 Vanagon Thermostat?
List,
I have recently gotten an '87 Westy and have been gleaning lots of
great info from you all.
Now, I have a question. This van shows lower temps on hotter days and
hotter conditions such as in town. When out on the freeway, the temp
goes above the led, when I would think it should go down.
If I pull over after a run on the freeway, with the higher temp
reading, the overflow tank overflows. However, the hoses to and from the
radiator are not hot at all, and the fan is not going.
In town, on hot days, the rad is nice and warm, the fan operates
occassionally, and the temp is about in the middle of the led.
This leads me to believe that the air cooling of the engine while
cruising on the freeway leads to a water temp insufficient to keep the
stock 87C thermostat open. When stopped suddenly, the thermostat cannot
react fast enough to bring the radiator online before the boil-over
occurs.
My question is this: Has anyone explored this problem before? Has
anyone put the 80C thermo from the '79 Audi 5000 in? (I did this
morning, but have yet to test it)
Any suggestions?
Thanks
Brendan
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