Packard Forum Index » Post-War (1946-54)

Hi folks,

I am just getting ready to start my 1953 327 with the hydraulic lifters.

I installed an aftermarket mechanical oil pressure gage (temporarily) on the very last (closest to the firewall) oil gallery tap.

When put together (but that was a long time ago) the oil pump was packed with grease. Of course when I was trying to figure out the distributor install and various things, it got rotated probably more than one revolution. The shop said that they "took the oil pump apart, it looked fine, so they just packed it with grease and put it back together".

I then took off the tee for the oil pressure sending unit, and back-pumped oil using a manual oil pump can and a hose and a barbed 1/8 NPT fitting, until the oil was going in without any bubbles. Not sure if that was enough.

Then I spin the engine some with the spark plugs out. I don't see any oil coming to the far oil galley. It's hard from where I am to see the oil pressure light.

Any thoughts? Should I take the oil pump out? Should I try to just take the oil pump cover off and re-pack with grease? (I think I have to take all the bolts off, but then just pull the cover off, don't try to take the entire oil pump out, I imagine I have to be careful the gears don't come out).

In the '1948 zero oil pressure' thread, it is discussed trying to turn the engine backwards while you pump oil into it. Is this necessary? Pump oil, turn pump backwards, pump oil, turn pump backwards, that kind of thing?

Thanks and Happy 4th!

I’ve never packed a pump with grease or primed it in any way, yet they always seem to work. I do use plenty of assembly oil on everything and make sure the pump gears are wet but would never use grease.

I think packing the pump heavily with grease runs a high risk of clogging the oil galleries. Perhaps you should take the pump out, clean it, and reassemble with assembly grease only.

I never found it necessary to pack an oil pump with anything other than a liberal coating of internal parts with heavy motor oil, or GL-1 gear oil.

Well, I took the pump cover off and i found there was some oil in there (along with some residue that looked like assembly lube, that's maybe what the shop used), hard to exactly tell how much. I tried to pump oil into the "inlet" and "outlet" holes and kinda made some progress, but most of it just came out the open side.
Then I tried again, and same result, no oil pressure. Then I took the pump off again and tried again, same result.

I just don't know how long I am supposed to wait. This engine was assembled with assembly lube everywhere, but the oil galleys are all dry, I presume it takes some time to fill them. Maybe I should consider filling those up?

I guess my next step would be to drain the oil and taking off the oil pan, which I am so not looking forward to. But I cannot figure out what could have gone wrong there.

Cheers!

JS; This is a very long shot, years ago I replaced a block in one of my 48 Packards with a marine application block. The block had a plug to prevent oil from going from the pump to the engine as it must have gone to an external cooler. Lots of gray hair arrived before I found the plug.

I'm not sure you can get enough speed to create oil pressure without some mechanical means like a drill that's commonly used to prime oil systems down the dist. hole.
If you did dislodge a "bunch of grease" into the galleys, that could also be your bane.

A long shot, but is the pressure relief valve stuck open? This is easy to check as the plug for it is on the outside of the pump housing. Inside should be a spring and the valve.

The oil pump is a positive displacement pump, and designed to be self-priming. With the pump and engine internals in good condition, even at cranking speed on the starter motor it should be able to deliver a small but measureable positive oil pressure.

Good point by JWL, an open relief valve would explain your condition.

"spin the motor some" was stated.
The oil light should go out, if it's pumping - he could not verify that, nor observe oil flow? Plus the grease where it didn't belong makes one wonder what's going on?
Sounds a lot like not pumping or turning fast enough or long enough. PD(gear) only pumps a small volume per revolution. Not enough revolutions, not enough oil flow.
Agree grease could've got in the PRV causing malfunction. I would still expect some flow with the PRV open?
One can rig a temporary light or DVM to the oil PS and observe if it's goes "on" from inside the engine bay. Or get some help.