Archived Oil pressure

[DavidBates]

Oil pressure gauge drops to 0 . After a few seconds returns to 40lbs. change d oil and filter. Still same problem. Any suggestions??. Engine has no knocks or strange noise's. Run's fine.

 

[JLandry]

David,



This is most likely a failing oil pressure sending unit. Failure is pretty common.



My truck is on the 3rd one in 120,000 miles. The first one failed around 7,000 miles.



Good luck,



John L.

 

[GAmes]

Do us a favor and post what year/model you are asking about. There are only about 5 different reasons.

 

[Sticks]

Plumb a mechanical gauge into the filter housing and verify pressure. Do not run the engine again until you can verify.

GAmes is right, if older model, you might have had the "Jelly Bean 'O Death" run through it.

 

[SRadke]

Sending units were common failures on 12 valves.

-Scott

 

[Bill Weber]

Mine does that about 30 sec. after starting in warm weather. Soon as I start the truck moving the press indication comes back up. It's probably a bad sender - just haven't got around to changing it.



Bill

 

[AH64ID]

To the OP, we need to know more about your truck.

Bill Weber, its due to that Amsoil Dual Filter in your sig, they are known to cause oil psi issues on 3rd gens, and aren't supposed to be used. The oil psi gauge on a 3rd gen is fake, there is only a 6psi switch on the motor so either the ecm sees pressure or not. It takes about 30 seconds of zero pressure to show on the dash. I would look into a different setup!

 

[Bill Weber]

AH64ID: Thanks for the thought, but I don't believe the press is really dropping. The filters are located below the original filter and are always full. There is no change in engine sound when press drops to "0" and no change in sound when the press comes up. Need to hook up a mechanical gauge but this only happens once in awhile.



Bill

 

[AH64ID]

AH64ID: Thanks for the thought, but I don't believe the press is really dropping. The filters are located below the original filter and are always full. There is no change in engine sound when press drops to "0" and no change in sound when the press comes up. Need to hook up a mechanical gauge but this only happens once in awhile.



Bill

What you are experiencing is exactly what happens with the Amsoil Dual Remote systems. It is possible its just coincidence that its a bad sender, but it sounds like the Amsoil system. I do agree it seems odd that the engine will react this way, but the oil psi switch is a 6psi swith, and idle pressure is 20 when the oil/motor are hot, and over 40 when cold thats more than enough to trip the switch. I have also read the Amsoil setup will send an air-bubble thru the system, but how big is that bubble? The psi switch is on the side of the block, not in the top of an oil passage, despite the fact that 20 psi of oil can easily compress air to over 6 psi. There is a reason Amsoil stated not to use the dual remote systems on HPCR Cummin's motors.



I would certainly add a mechanical gauge.

 

[Bill Weber]

AH64ID: Thanks for the further info. I will install a mechanical gauge and see what happens.



Bill