Re: Zero Oil Pressure 1948 Packard

Posted by JWL On 2020/10/7 10:20:32

Before going to all the work of removing the pan to check the float pick up screen and pipe, I have a recommendation.

I think that when you installed the new oil pump the pump may have lost its prime even though you squirted oil onto the gears. I recommend re-priming the pump. This can be done two ways.

One is to remove the pump cover and fill the gear chamber with a light grease.

The other is to pump some oil back into the pump.

Remove the fitting and tubing that supplies the filter and gauge sender unit.

Screw in a ⅛" NPT barb fitting. Slip a 5/16" or ⅜" hose on the fitting.

Then with an oil dispenser (pistol type oil can or other) pump about a quart of oil into the hose.

Reconnect the fittings, tubing and gauge.

Regardless of the method used crank the engine over with the spark plugs out. Watch the oil pressure gauge for a reading or remove one of the oil gallery plugs on the lower RH side of the engine and watch for oil to be pumped out.

If this does not work, check the pressure relief valve in the pump. It could be stuck open.

If none of this works then drop the pan and see what is going on with the oil pick up float screen and pipe.

One more thing: The pump cover gasket is very thin - like printer paper thin. The pump may not be able to prime if a too thick of gasket was used.

Hope this helps.