Hi List,
I am helping a friend research a problem with his TR6 and need your help.
A Little background first.
The engine was recently rebuilt and part of that rebuild was new std. size
pistons and rings. The engine uses massive amounts of oil. He drove from
Cincinnati, to a meet in Michigan this last summer and it used 5 quarts of
oil on the way up which is probably about 4-5 hours away I am guessing. The
engine seemed to run fine otherwise, no excessive smoke or leaking.
Our group disassembled his motor last weekend and found a lot of carbon on
the valves which is understandable with the oil usage. The pistons looked OK
with no broken rings. The ring gap is huge though, over 0.025 which was the
largest feeler gauge I had. I seem to remember the ring gap should have been
0.012 to 0.018. We are thinking the problem lies in either the
piston/cylinder clearance and/or the ring gap. Talked to Ken Gilanders and
he suggested that we should measure the piston to cylinder gap which we are
planning on doing ASAP. He thought that 0.006 piston to cylinder gap at the
piston skirt would be optimal.
We want to measure the cylinders to see if they are in spec. diameter wise
first. Then determine if he needs new pistons or just correct rings.
In looking in two motor manuals, there was a reference to a Class A and
Class B cylinder diameter but no specs for 0.010, 0.020 diameter tolerances.
Does anybody have that information and be able to email it to me off list?
We are planning on getting together again soon to do some more measuring and
that information would be great to have.
Thanks,
Dave Connitt
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