Some may recall that I've been anxious about the issue of valve/head/piston
clearance in my newly machined engine. Tonight it passed the modeling clay
test. What's that, you say? I put a layer of modeling clay on top of the
head/piston, within the head gasket opening area, in the vicinity of the exhaust
valve, i.e., over the 'eyebrows'. I then installed the head and valve train and
torqued it to spec. Adjusting the valves was done very carefully using the rule
of 9 so as to minimize the crank rotation. After the last valve was adjusted I
turned the engine (by hand) two full revolutions. I then removed the head and
checked the clay. BTW, before installing it, I sprayed the head combustion
chambers with WD-40 to avoid having the clay stick to the head
or valves. Inspection of the clay shows a very slight impression from the edge
of the exhaust valve. There is at least .100" of clearance.
The reason for doing this was because I had to install .060" over pistons
and discovered that the head had been milled by at least .100". Many thanks to
those listers that helped me with this issue. As usual, Barney's encyclopedia
was invaluable.
--
Bud Krueger
http://home.ici.net/~bkrueger/
52TD
77MGB
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