LML Gang,
Doing the annual on my 320 this week. Compression
check shows 77-78 on cylinders 1, 2, 4. #3 is 75 and I hear pretty good
leakage through the exhaust, indicating a leaking exhaust valve. I’ve
had no indication of sticking valves or morning sickness. I pulled the
rocker cover and there is no abnormality there. This engine is typically
run lean of peak at power settings of 55-65% power. Oil changes every
25-35hrs. Engine has 623hrs since new.
My question to those of you who are much more experienced
with the Lycoming 4-cylinder engines, is what should be my next course of
action?
·
Do the valve lapping procedure per the Lyc
service instruction?
·
Start using TCP and re-check in a few
hours?
·
Go run the engine hard and re-check the
compression?
·
Something else?
I really want to nip this in the bud and not end up with a
burned exhaust valve, requiring pulling a jug.
Appreciate your thoughts and responses.
Cheers!
Dan Olsen