Quick oil pressure Q

[Devilfrog]

So since adding a mechanical oil pressure Guage ... I've been seeing some interesting values. Factory Guage reads around 40psi unless idling,(it does read higher cold though).
So just thought I'd ask the masses, trying to decide if I need to swap out the oil pump or run till she's done.

Hot oil pressure, after 165km on highway
Idle


1500rpm


2000rpm


2500rpm


Motor has 238K km's and saw a poor life before me. Idles fine hot, surges a tiny bit cold, has loads of power despite mirror polished cylinders, 32" tires and 3.07gears...

Some valve train noise (due to old 92 head used).

And advice?
Thanks

 

[iluv83vettes]

I think I remember reading the value for needing work done is 13PSI for a hot idle, so you might be close. I also think that was for rebuilding the engine (you mentioned the mirror polished cylinders) not replacing the pump, but I could very well be wrong.

Also, is your alternator working?

 

[Devilfrog]

Yeah, it does that when the lights and fan are on. Battery voltage was actually 13.7v with the motor running. If I cut the accessories it comes up again. Just another electrical gremlin I have yet to get to (the radio circuit is only pushing 5v so they may be related).
It's all in my 88 so ... I'm slowly picking away at the issues. Currently everything works, but the fuse box shows the tales of previous owners with low brain cell content (looks like they hammered at it with a screwdriver).

Other than the valve tapping, an exhaust leak she runs like a raped ape.

 

[DieselSJ]

Trust the mechanical over the electrical.

That being said, you are within spec. More likely that your mains are worn than the oil pump being worn out, so swapping the pump probably won't gain much.

The cool thing is that you can swap main bearings with the engine in the vehicle. If you are tearing in to do the pump, throw a new set of mains in at the same time.

 

[87manche]

your volt gauge sucks like all renix ones do.

Fix the bulkhead connector, take a hard look at the ignition switch connector, bond the dash frame to the chassis with the extra stud by the parking brake mechanism.
Will likely get your gaue reading correctly and make everything in side the cab work betterer.

as to the oil pressure, if it's not clacking in the bottom end, i'd run it.

 

[IllianaXJ]

My 95 XJ shows just above 0 at hot idle on the factory gauge. It doesn't make any noise, so I don't worry about it. The early XJ/MJ gauges aren't really known for accuracy.

 

[old_man]

Don't worry, your numbers are fine and pretty much typical for XJ's.