Date: Sat, 1 May 2004 10:56:05 -0400
Reply-To: walt spak <b20swalt@CITY-NET.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: walt spak <b20swalt@CITY-NET.COM>
Subject: Re: Cooling strategies, color coded, etc.
Content-Type: text/plain; charset="iso-8859-1"
List,
Just my experience and my own theory as to why the heads corrode.
I have had at least 6 Vanagon engines apart and have successfully replaced
head gaskets in 4 of them. I have never seen any corrosion on the surfaces
that the coolant normally comes in contact with. All of the corrosion has
been on the "dry" areas of the head that are in contact with the rubber head
gasket.
I believe that as the head gasket goes through heat cycles it gradually
becomes hard and does not seal against the head as well as it did when it
was new. I think that condensation builds in the areas that are not sealing
as well as they did. I would think that this would happen after an engine
cools and would be affected by ambient temperatures as well. I would also
guess that short trips would accelerate the corrosion. In other words, I
think the leaky head gasket comes long after the corrosion.
Eventually between the gasket hardening and the corrosion you begin to see
coolant seeping out of the gasket seam.
I have never used VW Autobahn brand coolant so I won't comment on it. I
have used a couple of major brand phosphate free "orange" coolants. My
experience with them is that they find leaks all over the place. Every time
you turn around, you find a different hose connection or thermostat housing,
or something else leaking. I have since just returned to using a major
brand "green" coolant and the leak problems have gone away.
I have put over 60,000 miles (trouble free, by the way) on my Boston Bob
rebuilt 2.1 and 40,000 miles on my 84 Westy with green coolant and have no
leaky head gasket yet.
Walt Spak
Pittsburgh PA
b20swalt@city-net.com
----- Original Message -----
From: "David Brodbeck" <gull@GULL.US>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Friday, April 30, 2004 10:29 AM
Subject: Re: Cooling strategies, color coded, etc.
> On Fri, 30 Apr 2004, John Runberg wrote:
>
> > Something causes vanagon heads to corrode, causing pits and the
> > resulting leaks which make otherwise decent vans dirt cheap. The cause
> > could be anything, but spending a couple dollars extra for coolant which
> > matches VW specs is cheap insurance for me.
>
> I tend to think the leaks happen first, and the pitting is caused by the
> leaking coolant. It doesn't make sense to me otherwise -- how can the
> coolant pit a surface it doesn't touch?
>
> Complicating this is that the early, slow leaks will evaporate before
> dripping to the ground.
>
>
> David Brodbeck, N8SRE
> '86 Volvo 240DL wagon
> '82 VW Vanagon Westfalia Diesel