What was found
(CAN) DURING RT ENGINE VALVE GUIDE INSPECTION, SB 388C, WE FOUND THE EXHAUST VALVE HYDRAULIC LIFTER, PLUNGER ASSY, PN78290, BREAK DOWN IN TWO PARTS. NO PROBLEMS WAS SUSPECTED ON THIS ENGINE. UNSERVICEABLE HYDRAULIC LIFTER HAS BEEN REMOVED FROM ENGINE. DURING INSTALLATION OF A NEW HYDRAULIC LIFTER, WE FOUND THAT THE PUSH ROD WAS INSTALLED, AT REMOVAL PN: 73547, WAS TOO LONG. A SHORTER PUSH ROD HAS BEEN INSTALLED IAW O/H MANUAL, TO GET THE GAP, AS REQUIRED IN O/H MANUAL. THIS PUSH-ROD WAS INSTALLED SINCE THE LAST O/H 996 HRS BEFORE.