Oil pressure either high or low, depending

[Jeff Erwin]

So, my 71 Superbee 440 has been showing very high oil pressure, so I though I would start by replacing the oil pressure sensor on the back of the engine. Start with the simple things. I purchased a generic sensor, even had a male and female connector on top. Now my oil pressure barely moves the needle.

Hard to believe the new one is bad, but is there a more specific sensor I need or are they really all generic? I suppose I will put the old one back in, is there something I should do about cleaning it first?

Not sure now if my pressure is high or low...

 

[440Coronet500]

Get a mechanical gauge and use the copper tubing. Should tell you what your oil pressure is. 440'

 

[twecomm]

Make sure you have a good ground to the engine block where sender screws in.

 

[hunt2elk]

I wouldn't bet the farm on the original dash gauge being accurate, they rarely are. Like stated above, get yourself an aftermarket mechanical gauge and plumb it with a copper line.

 

[69Bee]

 

[1 Wild R/T]

"I purchased a generic sensor, even had a male and female connector on top."


You can't throw a sender on that is generic and not matched to the needs of the OE gauge & expect it to work....

You need a STANDARD MOTOR PRODUCTS PS59

 

[Jeff Erwin]

Perfect. Thanks. Will get one today and see what happens.

 

[70chall440]

What is "high" pressure?

 

[Jeff Erwin]

No number as I only have the gauge in the dash, but I call it 'high' as the needle is just below the last mark on the right. When I put in the new sensor it moved to just above the first mark on the left.

 

[70chall440]

Well my 440 in my Challenger runs 75+ cold and a client's car with a 440 is running closer to 100 psi cold. All this said, you really need a good mechanical or quality electrical gauge. I stopped running mechanical gauges a few years ago and now use quality electric gauges (Autometer) because I had an issue with a line breaking inside the car (fortunately I caught it when the engine was not running).

 

[whyjay]

Get a mechanical gauge and use the copper tubing. Should tell you what your oil pressure is. 440'

Agree with this. Also once you get the correct sender install with a “t” inline so you can compare dash and mechanical gauge readings. Once you are confident with the dash readings you can remove the mechanical if so desired.
I just went through this with my 71 Sixpack.

 

[Jeff Erwin]

OK, got the correct pressure sensor and installed it. The dash gauge now moves to about the 75% mark and fluctuates a little, which is what I expected. So, what did we learn?

1. "universal" isn't.
2. They do go bad.

 

[440 Charger]

So, my 71 Superbee 440 has been showing very high oil pressure, so I though I would start by replacing the oil pressure sensor on the back of the engine. Start with the simple things. I purchased a generic sensor, even had a male and female connector on top. Now my oil pressure barely moves the needle.

Hard to believe the new one is bad, but is there a more specific sensor I need or are they really all generic? I suppose I will put the old one back in, is there something I should do about cleaning it first?

Not sure now if my pressure is high or low...

What is the pressure reading?

 

[Jeff Erwin]

Well, with the old pressure sensor, the oil pressure gauge was at about the 90% mark, no idea what pressure that would relate to. It would never move, which is what caused me to replace the sensor. With the new sensor the pressure starts out at about the 60% level, then as the engine warms moves to the 75% mark, but actually fluctuates a bit when at idle, so I think things are working as they should.

 

[440 Charger]

Well, with the old pressure sensor, the oil pressure gauge was at about the 90% mark, no idea what pressure that would relate to. It would never move, which is what caused me to replace the sensor. With the new sensor the pressure starts out at about the 60% level, then as the engine warms moves to the 75% mark, but actually fluctuates a bit when at idle, so I think things are working as they should.

Did you ever get a mechanical gauge on ? Psi matters a bit like my 440 runs around 75 psi.