Increasing oil pump pressure

[Dr Morbius]

I have 2 1954 senior Packards, one of which has a rebuilt engine. I recently added 2 oil pressure gauges on each and found on my rebuilt Packard an oil pressure of 32-34 lbs. cold and 23lbs warmed up. On the other non-rebuilt engine I get 19-20 lbs. cold and 8 to 9 lbs. warmed up. I noticed there's a spring attached to the top of the oil pump and wondered if , for now I can stretch the spring out a bit and would increase the pump's pressure. Would that work? .....Steve <img src="http://forums.aaca.org/images/graemlins/crazy.gif" alt="" />

[Guest Randy Berger]

You can add a washer(s) of proper dimension to increase the pressure. I wouldn't attempt to stretch the spring as that is too imprecise a method.

[Dr Morbius]

Just an update, a question, and a thank you. The thank you is to Randy for suggesting washers instead of stretching the spring. I should have thought of it, but I didn't and that's what makes this forum great! Adding springs is simple and elegant. The update is I put first 3, then 2 more small washers for a total of 5 and my pressure went from 20 lbs cold to 38 lbs cold which is good and after 25 miles of driving {hot oil} at idle went from 7-8 lbs to 11-12 lbs. Not as big a bump as I would have liked at idle but still better as it has increased. Now my question and this includes V-8 owners too! What is the correct pressure at hot idle for Packard cars? The good book says 40 lbs for driving conditions but that's pretty vague to me. How 'bout it guys? .................Steve

[Dr Morbius]

Like I said , does anybody know what the correct Packard oil pressure at hot idle is ? <img src="http://forums.aaca.org/images/graemlins/confused.gif" alt="" /> I'm using 15w-50 synthetic. ................... Steve

[Guest imported_Speedster]

Enough to keep all the moving parts Oily, is all you Need.

As long as it Don't get below 10 psi (actual pressure at bearings), I Don't Worry about it. <img src="http://forums.aaca.org/images/graemlins/smile.gif" alt="" /> (Dash gauges and senders are sometimes Not very accurate)

Don't forget 'Too Much Pressure' can be Bad also. (gaskets and seals don't like it) <img src="http://forums.aaca.org/images/graemlins/frown.gif" alt="" />

[Clipper47]

I agree that hot oil pressure at idle is not a big concern. I have T'd in a pressure guage at the line where the pressure sender unit is located. The guage pressure using 15/40 Shell Rotella T is 40lb.@ cold idle but after a highway trip in summer heat the dash guage shows about 15lb. and the inline guage shows only about 5. The engine doesn't seem to mind as the lifters and bearings all run quiet.