Have you measured the cylinder diameter with an inside micrometer? The paperwork that came with the piston should give you a reccomended skirt clearance, and the cylinder might need to be honed for a proper fit. Never, ever assume a part will fit just because it's marked the same as the one that came out. Correct piston fit is extremely important and the normal clearance is approximately the thickness of one strand of hair. Not much room for error! We used to check piston fit with a long feeler gauge blade and a spring scale. Now it's usually done with a dial bore gauge and a micrometer.
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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