What was found
DURING SCHEDULED OIL CHANGE, OWNER REQUESTED A COMPRESSION CHECK BE DONE. NR 1 CYLINDER WAS LOW AT 28/80. FURTHER INVESTIGATION REVEALED THE FOLLOWING: PISTON CRACKED FROM SKIRT TO FACE AT 6:00 O'CLOCK POSITION. TOP COMPRESSION RING BROKEN AND CYLINDER WALL SCORED. THIS ENGINE ONLY HAD 30 HOURS SINCE PREVIOUS COMPRESSION CHECK WHICH WAS WELL WITHIN TCM CRITERIA. SUBMITTER RECOMMENDS COMPRESSION CHECKS BE DONE ON THESE OLDER ENGINES ESPECIALLY IF TOTAL TIME IS UNKNOWN AND TSMOH IS MID-POINT OR BEYOND.