Oil Pressure

[CptTom]

Need help- I re-assembled my series V after a nine month pause. Changed the oil and filter and I now have no oil pressure. When the car was disassembled to replace the transmission it had 40 psi. I didn't distrub the internals of the motor. Any guidance what may have happened to the oil pressure would be appreciated.

Tom

 

[sunalp]

Check you oil pressure relief valve, it's probably stuck.

 

[DanR]

Odd that you should be having "no oil pressure".....

I was just reading of a major culprit "pressure valve".... might not be your problem but would be worth checking out.

The article I just read was in the new "HORN"

 

[CptTom]

Thanks for the response. I removed the oil filter and it was empty. It would appear the oil pump has expired . Why it would function perfectly until the car was laidup for repair and not function after repairs were completed, baffles me. I hope the motor is OK. As a matter of practice I never start the motor after any prolonged stoppage without removing the spark plugs and cranking her until pressure builds. Next week the pans comes off and we go from there.

Tom

 

[bernd_st]

Empty oil filter is bad news. If the oil pump worked before you may try the following:

- Take off the oil filter
- Fill oil into the holes in filter block
- Turn/ prime engine backwards
- When the first fill of oil dissapeared refill a bit again
- Screw filter back on
- Start the engine and watch the oil pressure instrument

In 9 out of 10 cases you'll have oil pressure afterwards unless your pressure valve is stuck open...

 

[Alpine Addict]

Silly question. Have you checked the oil level?

 

[Shannon Boal]

Oil pump parts maybe worn: gear end clearance/float and gear to gear clearance excessive. Figure out how to prime it and it should last a while....or repair pump to specs.... or prime it with motor honey maybe, remove distributor and spin pump backwards, sucking in STP or heavy oil from squirt pump. Maybe preventative help from Amsoil AME 15W-40: this does not shear-down and thin out, good for antique motors....My two cents, after inflation, Shannon
PS, if you pull that pump apart, the gear end clearance can be corrected with a flat block and sandpaper....measurements made with feeler gauges and straightedge..0.002-0.004" including any gaskets.... please confirm this info, (I forget stuff....)

 

[RootesRooter]

Unless you put in the wrong dipstick after the re-assembly, this is about priming the system beforehand. It is NOT about stuck PRV's or sudden excessive clearance in the oil pump.

Prime it as two posters have suggested. Then start it again. I've run mine for no more than 10-15 seconds without seeing the needle kick, then let it sit for a few minutes before re-starting. Have patience. The needle WILL eventually pop up to the normal cold psi you had previously.

 

[Shannon Boal]

There may be risk in running the engine to prime it, and, to be fair, I have seen it work with no problems.....Have seen two engines damaged that way; an Oldsmobile 305, and an Alpine V. Both stuck, with babbit metal transferred to crankshaft. Now, a "dummy shaft" can be used in place of the distributor, powered by an drill motor, will give you fast pump speed and no risk.

 

[CptTom]

Great feedback, thanks to all who responded.
The oil pump is almost new, installed 2 years ago during an engine rebuild. Since the rebuild the car has been driven only about 200 miles. Oil pressure has been a rock solid 40 psi. This year the motor was removed to install a rebuild transmission. I did drain the oil and replace the filter after the engine was bolted back into the car. I think I will try the prime the oil pump suggestion first, before removing the pan and checking out the oil pan.

Tom

 

[Mike O'D]

You absolutely can not use a dummy shaft to turn the oil pump on the Alpine engines! The pump gear is driven off of the camshaft.

 

[Tim R]

Remove the plugs and quirt some oil down the bores, remove the power feed to the distributor and turn the engine over on the starter. You will start to see the oil pressure gauge rise. Once you start to get pressure put plugs back in, put power to the distributor and I suspect that it will run properly. This is what we do and it never fails.

Tim R

 

[Shannon Boal]

Well I did not remember that at all! I guess you could disconnect rocker oil pipe and pump it full of oil....or the oil gauge tube. It is weird, to me, that a newish pump would lose prime like this. It has to fill the oil filter after it primes and begins pumping.

 

[Gordon Holsinger]

Well I did not remember that at all! I guess you could disconnect rocker oil pipe and pump it full of oil....or the oil gauge tube. It is weird, to me, that a newish pump would lose prime like this. It has to fill the oil filter after it primes and begins pumping.

Old time mechanic trick pack the rotors in the oil pump with Vaseline it causes the pump to pull suction !

 

[CptTom]

Unfortuately I have to put this project off a couple of days due to the need to keep peace on the home front and attend to Christmas lights etc.. After i'm caught up I'll have anothe go at the car and update the progress.

Tom

 

[Tom H]

As others have noted you'll need to prime the pump. But first clarify that the engine DID run at least briefly when you saw no oil pressure, It's not 100% clear IF it ran or how long you let it run before shutting it down due to no oil pressure.

Assuming it did run, then follow Bernd's suggestions. But I must admit I don't understand what he means by "Turn/ prime engine backwards". Backwards??? Also I suggest you put some oil into the filter. And assuming the oil cooler hoses were disconnected during the project I suggest you fill the hoses with oil as well. 99% likely you have an air block somewhere in the oil path,

Tom

 

[CptTom]

The saga continues - Yesterday I disconnected the oil cooler return hose , elevated the end of the the hose and filled it with oil. This filled the oil cooler and the oil cooler supply hose with oil.. The oil cooler supply hose connects directly to the discharge flow from the oil pump. I put a clear plastic bag over the end of the oil cooler return hose , removed the spark plugs then cranked the engine over. No oil discharged from the oil cooler return hose. This would seem to indicate no discharge from the oil pump. Now today I dropped the oil pan and removed the oil pump. I opened the oil pump up and it appeared to be in great condition as it should as it is a new unit with very little time in service. Next I assembled the pump, place the pump in a container and added just enough oi to cover the pickup pipe for the pump. Now I turned the pump by hand and the pump picked up the oil and discharged it from the pump discharge pipe. When I cover the end of the discharge pipe with my finger the pump became very difficult to turn by hand due to the discharge obstruction caused by my finger.

Where to go now. It appears the oil pump is functioning properly but the discharge stream of the pump is not getting past the oil cooler. I think I will take the oil cooler and oil cooler adaptor out of the system and see if that resolves the problem.....

 

[husky drvr]

Tom,

With the pump out, did you check to see if the pins holding the drive gear had sheared? I think that to be unlikely but worth a check if the pump is out.

Also, any possible damage to the gear teeth on both the cam and oil pump? Again, not likely if the engine has been running as assembled, but easy to check if things are apart.

If your engine was running successfully with the oil cooler previously, I'm not sure how it would stop working due to a short period with no use. On the other hand, if the oil filter is defective and not allowing oil to flow in due to a rusted or otherwise sealed anti-drainback valve, you could have the same apparent problems.

Just a few thoughts - HTH,

 

[alpine_64]

Did you put a new gasket under the oil filter base?... There are 2 types one for early 1 for late.. And they will fit on either.. But passages are different and would block some ports....

Just a thought

 

[Tim R]

As Alpine_64 says, also if you get the gasket incorrectly positioned beneath the oil filter base (the wrong way round) it can give you this problem.

Tim R