How about a little history on the engine? Has it been run regularly, or is it a recent "wake up" from a long period in storage? It's possible you've got rings that aren't free in the piston grooves from being stored long term. If that's the case, try adding 2-3 quarts of Diesel fuel to a full crankcase of oil, and run the engine at a fast idle for 30 minutes or so- - - - -no driving or loading of the engine, just let it spin freely at 1500 RPM or so for a half hour, then drain the oil/diesel mix while it's hot. The rods and crankshaft splashing into the solvent mix will wash the inside of the engine better than any amount of scrubbing can do, and if the rings still have any tension left they might re-seat themselves on the cylinder walls. If not, you've just done a good cleanup before a re-ring job gets done.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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