No oil pressure

[62 speedster]

Have 74 2.0 been in heated storage for many years. Car will start but no oil pressure. Loosen the oil filter and removed spark plugs and spun motor still no pressure. Ex track car with external oil cooler. Any help would be greatly appreciated. Is it possible for the pump to loose it prime from sitting so long???? Any ideas!!!!

[Dave at Pelican Parts]

I haven't had it lose prime, but it didn't want to prime after a rebuild. It might have lost it, though. I was able to prime it by a kind of half-*ssed method of squirting some oil up the pickup with a turkey baster.

It may be possible that the oil pressure control piston is stuck. If it gets stuck open, it could dump the oil straight to the sump. There would be very little pressure building in that case.

In that case, you would remove the plug (looks like a huge screw you would use a flat-heat driver on) and see if the piston in there moves freely.

Oh, there is an O-ring where the oil pickup tube feeds into the main oil galleries. If the pickup tube comes out of the passage there, the pump will pretty much just pull in air instead of oil.

I can't think of anything else off the top of my head...

--DD

[62 speedster]

Is it possible the oil pump needs to be replaced???

[Dave at Pelican Parts]

It is possible, but I don't think it's that likely. You can pop the pump off the front of the engine and check it for damage or excessive wear or warping or some such. I believe it is four bolts and a very tight fit for the pump in the case.

--DD

[John Rogers]

We need to consider what type of pump we are dealing with here and how the oil system in a type 1, type 4 or even a six is setup. First off, the oil pump is a gear pump meaning it is nearly a fully positive displacement pump (some leakage past the gears) and since we have a wet sump setup as far as the pump is concerned, once the pump starts turning it will pump oil. This is also true of a six even though they are a dry sump tank setup, much oil drains into the case when shut off over long periods of time. If there is no pressure either of these is not happening:
- the pump is not turning and since it is a mechanical connection I would rule that as a last resort.
- There is no oil at the suction, either the sump is empty OR the suction/strainer is plugged. This is easy to check by pulling the sump cover, The suction can be checked by pumping oil from an external source into the suction of the pump. Remove the pressure gage fitting to see if any oil comes out from the top.
- The oil pressure line is plugged, check this by putting some oil in the engine opening and see if it drains away. Try putting some air pressure into the hole and see if it blows out the bottom sump cover from the suction line.
- As Dave said the oil control piston could be stuck and this is easily checked by pulling it.

[62 speedster]

Thank you both for great info. I have already removed sending unit from top of motor and no oil pumps out of the opening. I will take some time tomorrow and pull the strainer and go from there.

[62 speedster]

Since this car has an external cooler with plated mounted under filter this bypass the stock cooler???

[Dave at Pelican Parts]

The most common plumbing setup for external oil coolers (using a "sandwich plate" adaptor between the oil filter and the filter console) will not bypass the stock cooler.

I'm not quite clear on exactly what you're asking, though...

--DD

[John Rogers]

A couple of things to suggest in addition, first make sure the coil wire has been pulled so engine will crank but not start. If you pulled the plugs, then leave them out and I'd suggest adding a bit of oil to each cylinder so the rings do not gouge up the cylinder walls too badly. Finally make sure that the batt has a charger on it so the engine cranks fast and there should be enough oil pressure from cranking to show on a gauge or make the light go out. With all the racing type four engines I had we always cranked it a minute or two until the gauge showed some pressure.

Another thought, if there is an adapter for the front oil cooler it is possible that the front trunk is filling with oil if there is a broken line or cooler so have you looked closely for pools of oil?

Finally, did the engine actually have oil pressure when it was parked long ago?

[62 speedster]

I'm on board with what you are saying. I will add oil to the cylinder I think that is a great idea. There is a deep sump with no filter with a extension on the pick up. everything looks good to me. I removed the plug from the pressure relief valve. The spring came out but not the valve. I removed filter and checked lines to the cooler, everything looks fine. The guy I bought the car from said there was oil pressure when he put the car in storage. Anyway that's the story. He owned the car since 76. Thanks for all the great info . You seem to know the motors quite well.

[62 speedster]

Dropped motor yesterday and dissembled front and removed cover from pump. Can any body tell me A easy way to remove pump from the block. I've tried everything to get pressure with no luck. By doing research it would appear the pump is the problem. Any advice would be appreciated.

[62 speedster]

End off gear broke going into camshaft. The pump has a aluminum housing with what looks like a Billet cover. Is this a type 1 pump? I want to keep external cooler, so what's the best pump to replace this with?

Which do your think is better cast iron or aluminum pump?