Getting head Gaskets to seal correctly:
Figure 8 and head gaskets
I have found that the OE copper figure 8 gaskets do not compress
one bit. The old ones that we have removed from engines are the
same thickness as the new ones that come with new sets of AE powermax
pistons and liners. They all measure .018" thick.
The steel gaskets measure .002" thinner and not only do they
have a tendency to corrode, they don't lift the liners up high
enough so they don't have the necessary projection and the engine
will blow head gaskets.
We used to have a lot of problems with high compression race
engine when there was .002" difference in liner projection in
any two adjacent cylinders or if a cylinder measured higher on
one side than on the other. We now glue a piece of copper wire
that is .012" thick into one of the groves of the steel racing
gasket with contact cement before we install the head gasket and
use silicone sealer sparingly around the coolant passages.
Since we have been using this procedure, head gasket problems
have totally disappeared! We torque the head bolts to 95# with
permatex "never seize " on the threads and then retorque the head
hot as soon as it is warmed up. It never needs to be tightened
again. It is a sure fix. It even will seal a head that is a lightly
wavy or weak.
In an emergency we have glued wire onto both sides of the gasket.
With a steel gasket, we have found that .012 " is the ideal thickness,
thicker will have a tendency to allow water to leak out the sides
of the head gasket and up the head studs, thinner won't seal as
Regards, Greg Solow
Then again in 2013:
.020" copper wire is really to thick. It does not compress enough, holds the head up to high, so there is a tendency for water to leak out the sides of the head and up the studs. We have found that dead soft copper wire between .012" and .015" is the ideal thickness to use. We glue it in place with contact cement or "gask-g-cinch" which will work like a contact cement. We still run thin beads of Silicone gasket maker around the two long head studs on the manifold side of the head to keep water from getting around the studs and causing them to rust & pit. 85 lbs ft. of torque is enough, with "permatex anti-sieze" on the threads and under the nut. It is important to use good hard head nut washers, like those from ARP. Retorque the head when hot after starting and warming up the engine, also to 85 lbs. ft. of torque. We use .003" to .006" liner projection with no more than .002" difference in hight between any tow adjacent liners.
The Engine Room
Morgan & Triumph Specialists
Santa Cruz, CA 95060
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