Re: Low Oil Pressure 356

Posted by Fred Puhn On 2014/6/19 23:31:03

My 1950 Packard had low oil pressure after I got it. I put in an auxiliary gage and found the pressure on that gage was not low and about double what the original gage said. I bought a nice Stwart Warner "wings" gage set that looks correct in the car and mounted it under the dash.

I am concerned that some of the advice you are getting may not be correct. I totally agree with getting the excess clearance out of the oil pump. However shimming the pressure relief valve will only change the pressure when cold, and the problem is when the oil is hot. Excess oil pressure when cold puts more stress on the pump and could create leaks anywhere there is pressure. I would not do that.

The oil you are using (straight 40 weight) would have more viscosity change with temperature than a multi-viscosity oil like 10W40. You could even try a higher viscosity than that depending on the weather. The multiviscosity oil should be used on any car that has a large viscosity change with temperature.

Also another thing I learned over the years in engineering is to make only one change at a time between tests. If you change more than one thing you will not learn what change did what from the test.

Good luck.