my last two oil changes i have noticed my oil gauge has droped from the m in normal to the the o. i would like to check my pressure with a manual gauge at the hpop. warm engine temp what psi ? secound do these rotory oil pumps get weak or just quit when its time. 95 7.3 245000miles. thanks for any input.

 

Check and clean the sensor on top of the HPOP, it is the one plug lead on top of the reservoir.
That is where the LPOP Pressure is measured.

And yes, the pumps can get a bit weak, but using one of the idiot gauges to judge if its bad isn't really accurate. So, a check like you're saying isn't a bad idea.

Did you change oil types?

 

First of all the Dash guage is a glorified Idiot light....If you want to test LP oil you need to plumb a line to a place like the port beside the oil filter or the Turbo Pedestal...If you want HP oil you need to use a 0-3000 psi guage and plumb into one of the oil rail pugs on one of the heads.....

 

like thanks for the great answers . i as you say, plumbed it in and got 12 lbs at warm idle. like i was looken for the averge oil pressure. like is 12lbs too much at idle or would be 4olbs at idle be good.

 

warm idle should be around 20lbs.

 

I have a mechanical gauge and I get around 20 psi warm idle like Glenn and around 55 psi above 1500 rpms warm. I even use the synthetic Rotella T6 5w-40 oil which isn't as thick so less pressure.

 

Only 20 lbs at idle? I never knew that. I assumed 35-40 at idle....LOL

 

thanks for the suport. so with that being the magic number would we agree that i should be looken to changeing the pump. im going for majority ruleing ha ha.

 

Clay at RiffRaff diesel sells mellings.

 

I would say if your positive that you have the gauge connected good and are getting a good reading, then maybe you do have a problem. Both my PSD's are 20lb at idle with the oil hot and 50lb running down the road. Cold I get 55lb at idle.

 

ya it was a solid connection. removed oil sender at hpop.plumed in ran truck 5 mins raised and lowered rpms always setteled back to to 12 lbs.no change in oil or filter. just a few more miles.

 

Oil pressure sensor is just a switch, it's either open or closed so at idle or running hard the gauge should read the same ... unless your alternator is going out and not keeping the batteries @ 14 - 14.5 volts at idle, which it should.

 

You know.

I should know that seeing the troubles I had with mine.

I don't know what would cause it to read a low number like that, even voltage wise.

When I had trouble with mine, it just flicked back and forth the whole trip. The connection on it was bad and the vibration of the motor was putting it on and off.