What was found
CYLINDER ASSY HAD EXTREME CLEARANCES BETWEEN VALVES AND VALVE GUIDES WHICH IS NOT INDICATIVE OF 307.0 HOURS OF OPERATION ON A CYLINDER ASSY. UTILIZING USAF SPECS, I.E., SODIUM FILLED DOME TYPE EXHAUST VALVES AND CLOSE TOLERANCE STEEL VALVE GUIDES. IN ADDITION, PISTON ASSY IS A FAA PMA P/N WHICH WHENTHIS ENGINE WAS OVERHAULED IN 1972, HAS BEEN CHANGED ALREADY, BUT THE ENG RECORDS DO NOT REFLECT THIS. THE R2800-52/99/101/103W O/H AND PARTS MANUALS SHOW SPECIFIC AND NON-SUBSTITUTABLE P&W P/N'S FOR THE PISTON INSTALLED IN THIS POSITION. THIS CYL ASSY SHOWS IN EXCESS OF 1,000 HRS OPER USAGE.