A R175A diesel engine in the spring before the overhaul of the maintenance of cylinder liner replacement, piston, piston rings, valves and races, connecting rod, the supply of three precision couplings, there are still difficult to start the fault, and barely started after the operation Strenuous, no significant increase in engine speed when fueling the door. The inspection found insufficient pump oil pressure, decomposition pump, found that the valve gasket was significantly scratched, and there is a fracture. Turned out to replace the original valve when the hand with a screwdriver pry out the valve gasket accidentally broken, so that the fuel pump high, low oil collusion, resulting in the failure. Replacement of a new oil valve gasket troubleshooting. As the oil valve gasket installed pressure, reduced diameter, tight hoop in the valve seat, pry easily damaged, therefore, the replacement of the oil valve valve should be replaced at the same time the gaskets.