Oil Pressure Gauge

[k20]

Ok, buttoning up the last few problems on my truck before I start DD'ing it again. Anyway, the oil pressure gauge is giving me a headache. Installed my rebuilt motor, fired it up, stock gauge shows about 30psi. Ok fine, little low in my opinion, but it works. I test drive it, and I notice at hot idle its 15...hmm pretty dang low imo, then at one point it hits 0 and Im like . So pull valve cover, gettin plenty of oil, so I change the sender for the guage thinking it has gone bad. No dice same problem. Today I install a mechanical gauge out of my CUCV, install it in a different port on the block, and the factory gauge is reading about 28, mechanical is showing 65

So, Im gonna try swapping ports between the guages and see if that does anything, maybe I f'd up when I reinstalled the motor and stuck the OP sender in a water passage or something. If that doesnt make the factory gauge work correctly, is there any kind of test for the guage or should I just bite the bullet and put in all autometers.....there goes my tax return...

 

[obijuan]

my aftermarket gauge will read about 25 at hot idle and the stocker will never move from straight up and down. mines screwed in near the oil filter. ive got well over 150k on my motor though. did you possibly have air in the line?

 

[dyeager535]

Just go get another factory gauge if that's the problem. They really don't go bad that often for how old they are. At one point I had about 6 of them, tested each one, I don't believe any of them had a problem.

Of course, you didn't change the sending unit did you? There are 80 and 60PSI units (80 is diesel) and the gauges themselves are different, so you can't mix and match.

 

[k20]

Yeh I changed the sending unit but put in the same sender that should be in the truck, so that shouldnt be the problem.

 

[bradshawtech]

Same story on my K5 when I put in the new engine. My problem went away when I swapped in a different factory guage from a used cluster that I had. How about the different ground straps on the block to the body and frame?

 

[4X4HIGH]

Did you use teflon tape on the threads of the sender when you installed it? If so remove the teflon tape as it can make the guage not read correctly. GM relies on grounds to activate things and if there is enough teflon tape or some other kind of sealer that might be your problem.

 

[tRustyK5]

My factory OP guage read 5 psi max with my 6.2. It was getting plenty of oil though. I swapped in a new factory OP guage from another diesel cluster and it reads 70 psi cold, 50 psi on the highway and 35-40 at idle when warm.

Factory guages do go bad. I had the saem issue with the fuel gauge in Canmore's pick-up that I bought off of him. I never read more than 1/4 tank when full, and didn't matter which tank I was on. I swapped in a spare diesel fuel guage i had and it works fine now. Full when full and empty when empty.

They're cheap enough that it's worth chucking another one in and seeing what that one reads.

Rene

 

[k20]

Sealer on the sender is just the crap that comes on the senders, IIRC its a reddish color, and yeh I know the factory gauges are easy to find, I think I have one in my garage, but there are 2 problems with that, first I have white overlays on my gauges, and I dont think Id be able to transfer it (yeh I know I know mallcrawler), and the next problem is that if I open it up, Im gonna wanna start modifying stuff, hence the thinking about autometers.

Oh, another question, does anyone know of an a-pillar pod that will work with 2 5/8" guages that is a close fit for our trucks? I know some of yall have used the jeep cherokee pod, but it is for 2 1/16. I already have a couple 2 5/8 in an overhead I built and was never happy with.