Date: Fri, 21 Dec 2001 10:56:01 +0000
Reply-To: Paul Mayfield <paulmayfield@EARTHLINK.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Paul Mayfield <paulmayfield@EARTHLINK.NET>
Subject: extremely high coolant pressure
In-Reply-To: <200112201900.u259et.21b.37tiu8v@emu>
Content-type: text/plain; charset="US-ASCII"
First of all, I'm an artist, not a mechanic.
1987 Westy
My pressure tank blew up once. It might have been a faulty unit,
but I've always wondered if the cap with it's tiny orifice could
get partially sealed by deposits from coolant and overpressure the
system. It doesn't make sense that the tank would fail if the cap
allowed the pressure to vent. Is the Vanagon cap design unusal compared to
other cars?
Questions: Is it possible to
1) replace the pressure cap from an Asian or 'Merican vehicle ?
2) could a pressure gauge be fitted to system to monitor the pressure
when hot? (I have noticed that the overflow tank level doesn't change
much from cold to hot)
and 3) could excessive pressure be a factor in the leaking head problem?
If the system has enough pressure to bulge the hoses, does it make sense
that it would push past the head seals over time?
- - -
BTW, I thought my heads were leaking last summer.
After driving a distance, a large puddle of coolant was dripping from
the engine area. Got under and saw coolant dripping from the
head-to-cylinder junction with whitish coolant deposits all
along the bottom of the head.
S(*&T!!! A leak from the right side head! 300 miles from home!!!
Hours later, after cursing the mickey mouse water-challenged VW engineers,
I got under it again in futile hope that I could band-aid it to get home.
After three hours of driving, dripping, looking- EUREKA! it turned out the
smaller coolant pipe above the head area was leaking and flowing down the
case to the head gasket area, then flowing down the side of the head gasket
to the bottom of the head gasket, where the deposits and leak became
visible. The leak creeped along the aluminum and was nearly impossible to
see until it hit the rubber head gasket.
Replaced the pipe junction gasket and no more leaks!
I wonder, how many heads have been replaced when the real problem was
this situation?
Paul Mayfield
'87 Westy
'81 Land Cruiser (also not-a-Heep)
> I got a quick question. I have been having problems with hoses rupturing
> and most recently the end blowing out of the big plastic tee on the right
> hand side of the motor. I am getting ready to order the replacement tee and
> want to get all the parts in one order if possible.
>
> Here is what I have going now. I have gutted the thermostat so it is
> running wide open. It was bad and had to cut it out on the side of the
> expressway...wasn't opening up.
>
> I am thinking that the problem (aside from the thermostat) is the pressure
> cap on the expansion tank not properly keeping the pressure.
>
> Am I on target with this assumption or is there more I should look at. I
> have already blown 4 hoses and t-stat and a tee fitting and gallons of
> coolant.
>
> All this just started happening in the last month. The engine is a brand
> new 2.1 rebuild from VWoA. I have 10 month/10,000 flawless miles on it.
