Date: Mon, 13 Apr 1998 03:42:45 -0400
Reply-To: Mark Rokus <marokus@VOYAGER.NET>
Sender: Vanagon Mailing List <Vanagon@vanagon.com>
From: Mark Rokus <marokus@VOYAGER.NET>
Subject: Re: Head Leak ?
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The Martins wrote:
> My 85 1.9 Vanagon has 122,000 miles on her. The P.O. did the heads himself
> (reseal only, I think) less than 20,000 miles ago. a minute after start I
> get so much condensation spitting out of the tail pipe, it will actually
> wet your hand. Is my head leaking ? What stage of severity is this ?
> About how long can I wait to fix it ?
> Also, I believe my refill tank cap is bad as water will flow into it
> but not come out of it. However, when the expansion tank ( the one under
> the hood is less than full and the engine idles, I get a hot( overheat )
> indication. As soon as the engine runs up 2500rpm or so it goes back down.
> The rad fan does not come on, I can force it on with the AC switch, but
> the condition doesn't change. I believe that there must be a "local"
> overheat as the rad sensor doesn't detect it. Can the water pump be
> "weak".
>
> Any in puts are apprecaited.
>
> Thanks,
> LJ
First....The good news... The seal between the combustion chamber and the
coolant area of the head rarely leaks. The moisture you are seeing is simply a
combustion by-product. Is Should decrease as the engine warms up. The leak
everyone has problems with is between the head and the water jacket portion of
the block. Usually manifested as a squirt from the head area when the engine
is reved up and warm.
Second... the probably good news... The symptoms you describe about low water
level warning that goes away when reved is probably just that... low water in
the system. Fill the expansion tank and when the system is warm, vent the
radiator. This may take a few attempts to get most of the air out but
eventually most of it will be gone. Low coolant will also prevent the fan from
kicking on. All of this stuff can be found in the manual (Bentlys) or in the
archives but that is the jist of it.
Third.... the bad news... If after you bleed the system to the point that the
expansion tank stays full for a while, and then start to experience these
problems again, start looking for the leak. Rear or front heaters, coolant
tubes ( metal near the engine especially), water pump, and radiator are all
known to be areas of concern. BTW, my heads wouldn't leak at idle. I had to
rev up the motor to build some pump pressure before it would squirt.
Hope this helps
Mark Rokus
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