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Hi all,

So in my infinite wisdom, I've decided to remove the oil cooler and welded a piece of curved pipe to the inside of the oil cooler cover. I also replaced the oil filter and changed the oil and now I have no oil pressure - zero ...

So my question is does anyone know whether the oil cooler has an effect on oil pressure. I'm starting to think that the restricted flow through the cooler might and by me allowing it to flow freely through a 1/2" diameter pipe I 'broke' it.

Any thoughts would be greatly appreciated.

Thanks!
Crin

Yes, the cooler (and full-flow filter) is in series between the pump output and the engine oil galleries.

So by me allowing the oil to free flow (bypass the filter) it's affecting the oil pressure? Just want to make sure I fully understand this before I break something else... Lol

Thanks
Crin

Crin, it's easy - just follow the oil flow. Pump output exits the block at the pressure relief valve, thru the cooler and filter, and returns to the block again. The relief valve has dual relief systems, the primary one to regulate the maximum output pressure (set to 55 max) and the secondary one to bypass the filter/cooler loop should the filter clog.

And just what is it that you are trying to accomplish? And maybe you can explain your modifications more clearly, perhaps with some pix.

OK new question -

I think it's my oil pump. I think it gave out. I removed the oil pressure regulator and started the engine and I expected to see a strong stream of oil come out the side of the block. I didn't see anything other than a small trickle of oil.

Would you agree that it's the pump? And if so, who rebuilds these?

Thanks again,
Crin

Well, if somehow the flow from the pump was completely blocked off it is possible for pump pressure to blow a hole in the crankcase. That can happen using heavy oils in very cold weather as well.

I would start by seeing if you can blow through the external plumbing that you modified. I don't know what kind of filter is on the engine, but they aren't supposed to flow backwards.

I know those coolers can be a problem, but usually after excessive oil pressure damage. I remember Billy Hirsch had a 34 Su8 and they thought that the higher the oil pressure the better and they blew the thing up with the resulting oil spraying out of the radiator cap.

The V-12 units are far more robust. Packard was learning.

If the plumbing is clear in the proper direction, the pump can be tested on the bench. Just pour some oil in it and start turning the shaft. It should spray out.

Is there any kind of a pin only arrangement holding the cam gear and pump shaft together or is it one piece or somehow keyed?

Not familiar with the plumbing between the pump and relief valve or the valve operation but If the output was blocked possibly excess force needed to turn the pump or open the relief valve could have caused a pin to shear.

I'm just now getting ready to pull the pan off the car. Got a newly rebuilt pump ordered from Max Merritt so off I go ... what are the odds that the day I decide to make some major mods to the car is the day the pump goes out on me ...

Thank you everyone for your input. I appreciate it.

Slightly off this subject but maybe a place for an answer.
I posted pictures and details of a replacement filter for the 39:Packard six but a comment by Tim Cole on this post raises a question that I would like answered before I fire my engine.
The lines for the original disposable filter on the 39 both were located on the bottom of the canister.
The new canister for the drop in flitter has one port on the bottom and one on the side.
I ran the higher fitting on the block to the upper fitting on the the filter.
If this is backwards and could affect filtering or oil pressure…simple to reverse lines

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