Date: Sun, 20 Aug 2000 14:12:00 EDT
Reply-To: Wolfvan88@aol.com
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Robert Lilley <Wolfvan88@aol.com>
Subject: Re: care of our Wasserboxer/WaterLeaker engines
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There is one other factor that was not mentioned.
It is: Pressure: The head gasket pressure on the sealing surface.
The head gaskets I saw, from the engines I took apart, had corrosion damage
on the sealing surface UNDER the head gasket area only and on the area where
the various water pipes are bolted to the head that had leaked. The
corrosion buildup actually cuts into the head gaskets, slowly cutting the
gasket into two in areas, and in other areas the corrosion build up reduced
the space the head gasket had to compress under thermal expansion of the
engine and CUT the sides of the gasket OFF, leaving nothing to hold the
gasket in place and the cause of sudden gasket failures.
On one head from my original engine had been replaced at 57,000 miles. When
I looked at it, they had spread the head gasket glue on the entire surface of
the head exposed to coolant. The corrosion was only in the area of the head
gasket under compression.
I think that over time, as the coolant is trapped under the head gasket, the
corrosion process starts and develops pocket of corrosion that slowly destroy
the gasket and sealing surface. The time to failure in a stock engine
depends on coolant type, time until coolant is flushed with new and HOW the
engine was put together.
Some fail early and others never fail.
This is WHY I and others have coated the sealing surface with some type of
aluminum sealant to prevent the problem from happening. I choose the ceramic
coatings to get an additional measure of thermal protection to length the
life of the rubber head gaskets.
The head studs breaking is from not using the proper coolant AND NOT CHANGING
it annually so the metal protecting properties of the coolant are USED up and
then the coolant starts attacking the engine as the coolant flows.
Resolution 3: RaceWare studs
I am leary of using different other than stock head studs because of the
different growth properties in the metal alloy used vs. stock. This can lead
to problems with the head sealing correctly after many heating cycles. The
studs do not stretch the same as stock. IN T1 engines VW went to larger
stronger 10 mm head studs from 8 mm to try to fix the studs from breaking.
Then the 10 mm studs started pulling out of the case.
VW went back to 8 mm studs but with 10 mm tapered ends and there was no more
breakage or pulling out of studs. I feel that stock is BEST JUST change the
coolant AND with the correct kind.
The studs cause the tolerances VW built in to decrease during thermal
expansion to be tighter. This increases the head bolt torque beyond design
and as the engine cools, gaskets will be compressed beyond the normal crush
and can become damaged over time causing failure of both head gaskets: metal
compression ring and/or rubber head gaskets. The studs will put more stress
on the case, as they try to keep the head on tighter, and may start to
actually pull out of the case over time causing a failure.
Using bigger head bolts is needed in a RACING engine on a DRAG strip with a
BIGGER engine, but can be detrimental to the life of a street engine.
With proper care and preventive care the WBX engines can see a LONG life.
Robert