Oil Pressure Low

[GCK]

Once I get the car warmed up the Oil pressure gets very low when ever I'm stopped and idling. When I start to go again the oil pressure gauge returns to normal. I recently replaced the oil pump and put in 20/50 oil but the problem is persisting. Any advice? Solutions?

 

[Seabronc]

That is a common problem with aging engines. It could be as simple as the oil filter you use. a cheep one can go into bypass easily due to poor quality control in the build process. It could also be your sender unit which also has a reputation for being flaky. My engine has the same problem but runs strong other wise. I use 20/50 and 2 quarts of Lukas and it never goes below 15 lbs. That is a little heavy for Northern engines in the Winter. If your engine doesn't start making knocking noises when at idle then there is enough oil being distributed. As a rule of thumb, you need about 10 lbs per 1000 RPM. You might want to do what many of us have done and that is to add a wet oil pressure gauge so you can see what the pressure actually is. If you change the sender unit DO NOT use Teflon tape on it. It depends on the thread to intake manifold contact for proper grounding. The threads are designed to make the seal.

Good luck,

>-

 

[GCK]

That is a common problem with aging engines. It could be as simple as the oil filter you use. a cheep one can go into bypass easily due to poor quality control in the build process. It could also be your sender unit which also has a reputation for being flaky. My engine has the same problem but runs strong other wise. I use 20/50 and 2 quarts of Lukas and it never goes below 15 lbs. That is a little heavy for Northern engines in the Winter. If your engine doesn't start making knocking noises when at idle then there is enough oil being distributed. As a rule of thumb, you need about 10 lbs per 1000 RPM. You might want to do what many of us have done and that is to add a wet oil pressure gauge so you can see what the pressure actually is. If you change the sender unit DO NOT use Teflon tape on it. It depends on the thread to intake manifold contact for proper grounding. The threads are designed to make the seal.
Good luck,

>-

It's a '91 with the 351, and I'm new to Bronco ownership. When you say Lukas, is that oil treatment? What is a sender unit? Sorry I'm not that familiar with engine parts.

 

[Bronc76]

Could also be cam, rod, or main bearings wore out. a sending unit is a device that sends or transmits info to a gauge. it could be mechanical or electrical.

 

[Seabronc]

It depends on the thread to intake manifold contact for proper grounding. The threads are designed to make the seal.
Good luck,

>-

OOPS! I meant thread to engine block contact.

Right about the engine treatment, comes in a quart bottle.

And yes, it could be and most likely is due to worn parts, but if the engine is otherwise strong you can keep it going for several years while you either save up for a new / re-manufactured engine. I say re-manufactured rather than re-built because a re-manufactured engine is near to new when it comes to tolerances and more parts are replaced.

>-

 

[GCK]

Thanks for the help. Hopefully it is electrical but I have a feeling it is mechanical.

 

[MotoRyan]

I recently replaced the oil pan and gasket in my 95 302. Had to rebuild oil pump in the process. Maybe it was paranoia but I found my oil pressure gauge dropping at idle for the first 250 miles. Was using the old FRAM oil filter for the first 250 just to flush out any debris from working. I heard that those filters sometime collapse, and I think there was debris in mine.

I also noticed oil gauge would only drop when the defrost was on, due to the compressor clicking on.

Set the idle to 800, changed oil (motorcraft synth blend 10/30) and new fram oil filter, haven't seen it do it since.

 

[Shadow_D]

I'd say it is the bottom of the motor... I had this happen with my Beast and I had to put a new motor in it. I could have rebuilt the motor myself but at the time I didn't have the space or equipment to do that so I had the Stealership do the work thinking I would have a good Ford Warranty HA! what a waste that was!