Update....
Giving the engine longer runs at full load.
The vapor from the breather tube is disappearing. Piston Rings seem to be seating nicely.
http://www.youtube.com/watch?v=FW-0-zmljT8 (http://www.youtube.com/watch?v=FW-0-zmljT8)
veggie
How many hours did it take for this to occur? I've got a fresh liner and rings in mine too and things at the breather seemed to settle down around 100+ hours.
This one was fairy rapid. About 5 hours of running at 80% to 100% load.
The GM90's have an aluminum piston with 5 rings.
veggie