Zero Oil Pressure (1 Viewer)

[mongoose2231]

So as of late, when I start my truck, it runs for a few seconds then shuts off. I have a mechanical oil pressure gauge and I realized that the truck does not build oil pressure right at startup. Once it shuts off and I restart the pressure builds up to 80 psi immediately. This is only when the truck sits overnight or for extended periods. I have done a bunch of searching here and on the Internets and I cannot find a concise answer. I consulted the FSM and I have a general idea of what it may based on what is listed in the trouble shooting section but before I start to delve into the problem, I figured I ask you fellas on here, maybe you can offer a shortcut to solving the issue. I just reopened the oil pressure relief valve and cut a coil off the spring and that resolved my over pressurizing issue I had for the longest time, even though I was running the extended valve. I am thinking to replace the oil filter and oil first and then see if that solves the issue.

 

[roma042987]

May be a silly question but have you checked the oil level?

 

[mongoose2231]

Yes, oil level is OK. In fact I rebuilt the engine in 2015/2016. Everything is well and there are no leaks. I am leaning to think that maybe the pump looses prime somehow. I will switch to a slightly thicker oil, I am currently running rotella 15w40. This issue started happening recently, after the truck sat for more than a year and a half awaiting a rear main seal replacement. After I added the turbo, I rerouted the crank vent hose into the intake pre-turbo, and when the engine got hot, the hose would kink and it pressurize the crank case, blowing out the rear main seal. I since have installed a Provent 200 and things are good now.
The only thing wrong right now is this issue with zero pressure at initial startup. If I give it a bit of "gas", the pressure will come on after a few seconds and she will not shut off.

 

[ceylonfj40nut]

Is your oil pressure relief valve stuck open? Dirty?

 

[mongoose2231]

Not really no, I just checked it. It did the same before I took my oprv out to cut a coil off the spring. So even with the new longer valve, the engine went well over 100psi when cold, right after starting. Then I took the valve out and I cut a coil off the spring and it now goes to 80 psi at cold startup but only after the second key. The first key will shut down after a few seconds due to no oil pressure.

 

[roscoFJ73]

Are we talking about the HJ60? This is a common problem involving the low oil pressure switch switching the edic to STOP. Disconnect the edic and hold it on RUN while a friend starts the engine. It should keep running. Lots of info on MUD if you search.

 

[duncanrm]

The thicker oil is likely to make it worse.. is the truck parked on a level surface? Facing up hill seems to make this issue worse for 2Hs.

 

[mongoose2231]

Yes, I am sure it's the edic shutting the engine down, but it is doing its job just fine because my mechanical gauge does not register oil pressure unless I coax the motor with the skinny pedal, or if I let it shut off and the restart it a second time. I did a lot of reading here on mud and the only case close enough to mine was a fella whose oprv was in backwards. That is not the case here.

 

[roscoFJ73]

my mechanical gauge does not register oil pressure unless I coax the motor with the skinny pedal

I dont think this is a bad thing to do. The moving parts still have oil inside them and the pressure comes up immediately. As engines age , they always take longer to get good oil pressure at idle.

 

[mongoose2231]

I will see what is what with time. The pressure always comes up on the second startup.

 

[gerg]

Oil filter drain back valve?

 

[mongoose2231]

Is this the same valve found in the top of the filter housing? That is some sort of pressure relief valve as well, isn't it? I don't think I saw anything in the fsm diagrams. Could you elaborate?
Thanks

 

[mongoose2231]

Made a video of the truck this morning. Starting cold, shutting down on its own, restarting and then shutting down after normal temp and testarting yet again at normal op temp. What gives?

 

[ceylonfj40nut]

Dumb Q. Have you checked if the pressure sender is working properly?

 

[mongoose2231]

Well, I can't see any issues with it. I have a 3 way installed in the factory location, which feeds mu turbo, my mech. gauge and my stock gauge. I must restate that this setup hadn't given me trouble in the past.

 

[gerg]

The rubber diaphragm on the top of the oil filter itself is suppose to prevent drain back. Might just grab a new oil filter and chuck it on.
It sounds a lot like your system is loosing prime.
Your mech gauge also seems very slow to reach max pressure although your idle pressure hot is very good. Has it always been slow to react?

 

[mongoose2231]

Since I installed the mech pressure gauge I kept an eye on it. I really don't remember how slow it was before versus now. I will install a new oil filter, I have a couple on hand.

 

[mongoose2231]

If you notice, the idle is like 450ish when cold, It should be 650 or so rpm. If i give it a tiny bit of gas to reach 650 or so rpm, the pressure climbs much faster! After the engine reaches normal op. temps it's all good.

 

[ceylonfj40nut]

Is your throttle linkage sticking when cold? Worth checking and “degreasing”

 

[mongoose2231]

The linkage is good. I just looked at it. I am going to have to replace the filter to see if that solves the issue.
I over-pressurized the engine at cold startup so many times with the bad oprv that the oil filter seal may be compromised.