New Cast Iron Oil Pump pressure low

[alamow]

We have fitted the new style cast iron oil pump to a 570 block and the oil pressure has dropped 4 psi to 32 psi Hot. I have read the TSB describing the +/- 6 psi difference between the old and new pumps.

Is it possible to shim the pressure regulator? What size shim is required to increase pressure by 5 psi?

[Rawze]

What else was replaced when the pump was?

[alamow]

Only the pump was changed.

The original aluminium housing pump has been refitted and oil pressure returned to normal 36 psi hot.

The engine has completed 150k on an in frame. The pump was not changed during the rebuild.

[marek4792]

Unfortunately oil pressure being in the low 30's with the new pumps seem to "normal" as scary it looks to see it that way. A fine example of engineers fixing something that wasn't broken..

[redbeard]

Curious as to why you changed to new oil pump, but then thought old one was ok to put back in. What issues were you experiencing that led you to change the oil pump

[Mattman]

I don't get how less is better.

Need to install 50psi oil pressure gauge so it will look like we have good oil pressure.

32psi on 100psi gauge is going to look bad.

Maybe we just need an idiot light.

[alamow]

The pump was not changed during the rebuild earlier this year due to Covid lock down causing parts shipping delays. We ran the new pump for 4 weeks without issue except the engine brake would not operate on MAX if the oil pressure dropped below 31.5 psi.

Did an overhead, checked cam bearing, crank bearings, filters etc before finding the TSB on this forum. Cummins neglected to mention the TSB.

Oil temp is 220 f with maximum spikes to 240 f. Hauling 80 - 130t

Fitted the original pump to see if the oil pressure would return to normal. The pump has signs of wear and will need to be changed hence the question regarding shimming the pressure regulator on the new style pumps.

When installing the new pump we shimmed the backlash as per the manual. According to the TSB shimming is not required. Not sure if that would make a difference to oil pressure.

[Mattman]

Does anyone make an aftermarket oil pump?

[Rawze]

(11-08-2020 )alamow Wrote:  ...
Oil temp is 220 f with maximum spikes to 240 f. Hauling 80 - 130t

...

High oil temps (240+) is a common sign of poor quality EGR-delete (or other custom tuning ) programming that is contributing towards excess friction. If you want the file checked/verified, just pull a copy out of the ecm some time and e-mail it to0 me and I will review it and tell you exactly what is in there.