My engine a Lycoming 320 used a liter of oil in the last two hours.
I pulled the plug and oil ran out. The bottom plug was soaked in oil. The last flight it ran fine, made the normal amount of power.
Pulled the valve cover and there was not an unusual amount of oil in it. Checked the drain tube, not blocked.
Checked compression good, same as the other three.

Puzzled, how did the oil get past the rings if the compression is normal?

Could a valve guide seal leak that much??

Ray
Grumman Cheetah, OM