Check the cylinder taper. Turn a piston to the bottom of its travel, and insert a piston ring into the cylinder, up against the ridge at the top of the ring travel. Stack up feeler gauge blades to measure the ring gap. Write that dimension down. Push the ring down into the cylinder about 2-3 inches, making sure to keep it square with the top of the block. Measure the gap again. Subtract the bottom gap from the top and divide by 3. The result is the taper wear in the cylinder in thousandths of an inch. Any taper exceeding around .005" indicates it's time for a rebore and oversize pistons- - - - -a re-ring job with tapered cylinders is a waste of time and money.
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
Love your enemies and drive 'em nuts!