The small engines I've serviced. I've had to pull a
rectangular cover from the side of the motor, which exposes
the valve springs. The clearance is measured between the end
of the valve stem, and the push rod. Have to turn the crank
shaft so the lifting pressure is released. As the engine
warms up, the valve stems lengthen due to temperature. So,
there needs to be a gap, to compensate for the lengthening.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"Jules Richardson" wrote
in message ...

The valve clearance. Over time the valve seats wear and
the gap closes,
not allowing the vlave to close completely. If the vlave
clearance is
less than .04, the valves MUST be removed and ground down
to the proper
clearance.

Yeah, I'll check them. Visually they look good (i.e. seating
evenly and
no other obvious major drama has occurred) but that's no
guarantee that
they're not worn so much as to be inefficient.

I've found the allowed clearances for that engine - 0.005 to
0.007" on
the intake and 0.009 to 0.011" on the exhaust.

cheers

Jules