Oil pressure gauge reading

[Just Jim]

I have the 500 hp Cummings engine and while driving over the weekend I noticed the oil pressure was reading between 30 and 40.  Is that a normal operating pressure?

[DavidL]

"The oil pressure you “see” on the gauge at the panel may or may be the actual OIL PRESSURE in the main oil gallery or the OP going into the oil filter. Between the sender wearing out over time or the gauge “sticking”, use that gauge as a base indicator only..

To your question:

Seeing 40-80 PSI at medium to high RPM’s seems average and 10-20 PSI when idling (engine hot) is normal. going below an actual 10 PSI when hot at a low idle below 700 RPM is quite normal–Nothing to worry about.

The only way to really know is to install a high quality liquid filled 0-200 PSI gauge on the engines main oil gallery—- Use a High Pressure #4 hose hose when doing so."

 

Cummins...not Cummings 🙂

[vito.a]

Most of our Monaco dash gauges use a Monaco installed oil pressure sending unit.  It's a dual output VDO part number 360 023.  One output is for the idiot light and the other is for the gauge.  You might try reversing the wires or installing a new sending unit.  The sending unit is on the passenger side down near the starter.  I accessed it through the rear bedroom access hatch.  

VDO 360-023 150 psi Pressure Sender 754059004761 | eBay

[Ivan K]

If yours is an ISM, the sender is near oil filter, driver side. I typically get 37 PSi on Scangauge with operating temperature 187F usually, while cruising around 1600 RPM. The analog gauge does not have that fine calibration readout but appears to be correct.

[philcarrell]

My 525 ISX runs 34-35 at 1500 RPM.  I called Cummins after I bought it and they said that was normal.  My 400 in the 04 Windsor run about 50.

[Just Jim]

Thanks everyone.  It is the ISM and it looks like 35-40 is about right.  Still fussing with the fuel gauge, so just wanting to make sure the others are working.