Just picked up this old pole saw and want to know what I should look for. Looks like some play were the shaft off the power head meets the large boom shaft. Gonna take that apart later. Compression is 75 PSI, piston moves around a MM or so by feeling in the exhaust port. Figuring I'll run it for the rest of the season (bush trimming) and then should I replace piston and rings or do these usually need cylinders, crank bearings? I didnt' see any scouring on the piston or cylinder through the port.