What engine do you have in that 54? Oil pressure relief valve is in the oil pump on most of these. Nothing more than a spring holding in a steel ball. Do you have oil flow to the valve train? Have you changed the oil yet? A can of motor flush of some sort might help get the gunk out. I used to recommend using kerosene, but too many people don't do it properly and ruin their engine.


Fred
52 3600
69 C-10