Chainsaw Repair

These are model airplane engines. Some planes are as big as a pickup truck.

The people like to see the rings have a good vertical wear pattern within an hour's running time. The cast rings do this well.

The hard rings, you can run them a whole season and they will only show a vertical pattern half way - usually from the top. The pilots feel they are loosing compression.

Typically by the time the hard ring is fully seated, it's time for a new piston/pin bearing, crank/rod, bearings/seals