black924S

I have zero oil pressure. To prime the pump I decided on the air compressor method. I pressurized the crankcase with OAS tube plugged and oil filter off and got air out of the center hole. So I plugged the center hole and got oil out of the perimeter hole; a steady stream with no air. Does this mean that my pickup tube is intact and that my return tube is broken? Is a broken return tube need necessarily be fixed? I never had one of these engines apart before so I could use the help.

1. OPRV seems OK
2. PS pulley aligned and bolt torqued to 155 ft(lbs)
3. Still cannot get the pump to move oil

mytrplseven

Did you replace the oil pump drive gear and the green shaft seal?

thomasmryan

While you are under pressure, spin the crankshaft with a socket. If you are trying to move oil through the oil pump assembly, it must rotate.

Edit...I am going to retract my prior statement. Pressurizing the crankcase really is NOT going to force oil through the pump and galley unless all returns to the pan are blocked. If you are putting the entire block assembly under pressure, there is no pressure differential to force the oil to go anywhere.

black924S

Thank you for the replies. But pressurizing the crankcase with the oil filter off definitely causes oil to flow out of the peripheral hole. I assume this means that the pick up tube is good and that the pump is primed. Please correct me if I am wrong. I am only beginning to understand the the design of this car. This car has been under neglect by past owners.

Update: The power steering pump is missing a bushing. The pulley on the crank seems to be in good shape. The bolt is tightened to specification. The thrust washer is dished side facing engine.

black924S

I haven't replaced anything yet.

thomasmryan

Right on....read this little tidbit on the oil flow. oil flow

Ian, Lart or plyhammer may have your power steering bushing. Ian probably has a kit.

Edit...looking at the cooler housing, the perimeter of the oil filter does run through the pickup, cradle, pump and cooler before it arrives but that could not confirm that is the only place oil is coming out. Can you hear any bubbling inside the motor while the pressure is applied?

This thread also. http://forums.pelicanparts.com/porsc...l-pump-qs.html

Tiger03447

@ my tripleseven: Is this mandatory during an engine rebuild? I can see replacing the seal, but the gear also , even if it shows no sign of wear? Is this in the WSM? Please enlighten me...Thanks

black924S

No bubbling. Just a smooth stream of oil. I would think that would adequately prime the pump.

odonnell

When you say you have no pressure, are you going off the electronic gauge or a mechanical gauge added for verification? The electronic senders are known to fail sometimes and shouldn't be relied on in times like these.

thomasmryan

If you have oil there, it is primed.

This thread is another method http://www.944online.com/cgi-bin/yab...num=1328734487

black924S

The engine sounded rather unoiled. I get the red light as well. And on top of that, I cannot get oil to come out of OPRV hole or oil filter hole while cranking. It think we have a true no pressure situation. Can we rule out the pickup tube based on the pressurized air experiment? I will remove the oil pan if I have to, but to do that unnecessarily would seem like such a waste of effort. How to tell if the pump is spinning?

Van

Absolutely not... If you have a cracked oil pickup tube, and pressurize the crankcase, oil will go up the tube to the break, then *some* oil will dribble out and back to the crank case, and *some* oil will keep on going to the filter (as you are observing).

However, if you try to move the oil via the oil pump, the pump will just suck the much thinner air through the crack, and no oil will get to the oil filter.

Did you rebuild the engine or something? If so, did you mix & match parts?

Dare

Are you sure about that, Van? I would think any crack in the tube would also be exposed to the increased air pressure in the crankcase (presuming the crack is above the oil fill line). If that's true, then I think the pressurized air would be forced through the crack, through the oil pump and out the filter hole, without moving the oil at all.

thomasmryan

most pick up tube cracks shown online are up near the bearing girdle...if it where my car, the pan and at least the oil pump cover would be coming off.

did you look at the pictures of the failed/scored pump?

StoogeMoe

I agree with Van. Any small crack will draw mostly air when under vacuum. Did you ever try sucking on a straw that has a crack in it? You get no soda!

You either have a crack in the pickup tube, or the sealant of the girdle or oil pump is compromised. Oil pump failure is also possible, but less likely. It could be so worn that it is not able to draw oil. All of these problems require major engine disassembly, so definitely double check that your oil pump drive gear is actually working.