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I'm fairly new to Packrad ownership and have aquired a '52 with a 300 8(327).
The car sat for many many years but after some minor tinkering I got it running. I dropped the pan and cleaned everything including the pickup screen. I'm running straight 30w.
At idle I have only 20lbs oil pressure and it does not rise when I bring the revs up. After a few minutes of running (and coming up to operating temp) the motor starts to "clack", I removed the side covers and noted that there was only one oil journal pushing oil.(the flow seemed a bit weak to me)
Does this indicate a weak oil pump? Clogged journals? It seems highly unlikely that every one of the journals would be plugged. How much oil pressure should I have at idle, the motor manual I have says 40lbs at 30mph, but I can't take the car up to that speed at this time.
Any help or ideas would be greatly appreciated.
Again I'm new to Packard but fairly mechanical. I understand that the oil pump has a built in regulator that cannot be adjusted?
Thank you in advance.

How is your Oil Filter plumbed? Have you checked the filter?

On the 51-54s the oil is picked up and delivered to the main gallery, then it exits out of the drivers side of the block where the oil sender is. Depending on how the oil filter is plumbed it works one of two ways:


Bypass Mode:
It leaves the side of the block via a 3 way Tee, there is a short pig tail that then connects back to the block a few inches about the outlet. This return inlet then feeds the upper end of the motor (valve-train).

The other side of the tee feeds over to the filter, and then drains back into the oil pan via and inlet below the filter. There should be some kind of restrictor in one of the filter fittings so the the valve train feed gets adequate pressure.

Non-By pass:

It leaves the side of the block via a 2 way Tee, which feeds over to the filter, and then from the oil filter connects back to the block inlet to feed the valve train. If the filter becomes clogged, or the line gets kinked, then you could starve the upper end of the motor.

As far as the oil pump is concerned, you can shim the oil pump pressure relief spring with a washer. This will increased the pressure required to open the relief valve.

Just so you understand shimming the spring in the relief valve of the pump only raises the maximum that the pump can produce before the relief valve opens. The amount of clearances in bearings etc. are the "leakages" and thus if shimming the pump doesn't raise the pressure, you're left with excessive bearing clearances or much less likely, a worn pump. But if the pump looks like it might have been off or serviced recently, you might remove it and check to see if too-thick a gasket was installed - this will dramaticaly drop the pressure by allowing the oil a "short circut" path across the face of the gears. At the same time, check to see if the cover plate is badly scored which would allow the same thing - if so it can be surface ground or a new one located. The gasket on the cover plate should be VERY thin.

The only pump "adjustment" was limited to the installation of a new spring.

Quote:
G'day JFH,
Congratulations on your new acquistion and to PackardInfo. I'm sure you'll get plenty of good advice from the experienced and knowledge members here. And I invite you to include your '52 300 in the Owner Registry here together with a pic, any known history and how you acquired it.

I removed and cleaned all the lines from the block to the oil filter canister. The filter is new, when I removed the cover to check if the filter was getting oil the canister was about 3/4 full. I did not see any kinks in the lines.
1. What should my oil pressure guage read at idle?
2. What does it indicate if my guage shows 20lbs (at idle) and does not increase with engine revs?
3. Why would only one journal be pushing oil?

2. What does it indicate if my guage shows 20lbs (at idle) and does not increase with engine revs?
3. Why would only one journal be pushing oil?

Though your hot, idling oil pressure with something like SAE30 oil should be higher, perhaps 30 or 35, it's not all that important. What is important is what the pressure is at road speed, say 25-40 mph - then it should be about 40 psi, though 35 would be marginally OK. Low pressure under those conditions with no other explanation would mean what we've indicated before, worn pump (unlikely), weak pump pressure relief spring, or excessive wear on the main and/or rod bearings or crankshaft.

The word "journal" usually means one of the crankshaft surfaces that either rides in a main bearing, or mounts a connecting rod, so I'm not sure what you mean.

I would expect bearings. Drop the pan again and plasti-gauge them. If that's not it, check the oil pressure relief spring and remove a washer, there should be several already in place. Also, it is possible that the relief valve is stuck open and too much oil is being bypassed. Take the pump apart and clean it thoroughly and make sure the parts all move freely.

Take these suggestions in any sequence you deem appropriate and good luck.

Remove a washer? Wouldnt that cause the relief valve to open sooner due to less spring tension?

I'm not sure how to quote a question from a previous poster,
Owen asked what I meant by "journal". I should have been more clear and said the oil passage hole where the lifter rides up and down.
I will remove and clean the oil pump today and let you know how that works.
1: There seems to be some debate as to removing washers (spacers) or not? Could someone clarify?
2: It seems to run quietly (when started cold) until the engine gets up to about 130 degrees and then starts to make the lifter (clacking) noise, any thoughts?
Thanks for all your help thus far.