Date: Mon, 11 Jul 2016 23:07:34 -0400
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: Cooling system over pressurizing?
In-Reply-To: <CAB2RwfgLU7YjMNPaY7jRVrO_b1+3yXTe9hs6Yh7DYGtNYQq-7g@mail.gmail.com>
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This is a symptom of combustion gasses getting into the cooling system. The forces between the piston and heads during the power stoke is immense. Just think of the pressure created in a cylinder to deliver 90 ft. lbs. of torque with less than a 3 inch stroke.
If caught in time I say I have around a 50/50 chance of successful repair by re-torqueing the heads. Use a beam or gauge type wrench so you can feel if a stud is beginning to stretch.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Neil N
Sent: Monday, July 11, 2016 4:58 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Cooling system over pressurizing?
Hi all. This is for a 1988 westy. I'm out of town on a camping trip.
I drive for about an hour, pull over, let engine idle. I don't hear a gurgling sound.
As soon as I shut off engine, I hear a gurgling sound from small hose connecting nipple on passenger side head to long engine bay coolant manifold. While hearing that gurgling sound, I see a rapid stream of bubbles go into top connection on my coolant expansion tank. My fill tank over fills with coolant, coolant spills out top of that tank. This lasts less than a minute.
This has happened twice on this trip.
I think there is a leak between a cylinder and head and that a compression or exhaust stroke is over pressurizing my cooling system. As was suggested before on this list (thanks Dennis!) a head may be lifting during longer drive times. It doesn't happen on short trips in town.
The passenger side head may have been replaced at some point. I do wonder if head bolts need to be torqued sown more. A risky proposition for an amateur!
Am I likely correct that my coolong system is over pressurizing?
This happened before on a road trip. I replaced the blue cap on expansion tank, this seemed to cure the issue. My thought is that if engine is pumping hot exhaust gas into coolant, if coolant temps are too high, this is causing the valve in blue cap to fail.
My hope is to nurse this westy home from cle elum WA ago Vancouver bc.
--
Neil n
Blog: Vanagons, Westfalia, general <http://tubaneil.blogspot.ca>
1988 Westy Images <https://picasaweb.google.com/musomuso/New1988Westy>
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