If the truck didn't start right after the oil change then maybe there is another problem. The hpop reservoir holds oil for on demand and startup. There should have been enough oil in the reservoir to start the engine and allow it to run for a short period. If the relief valve is missing the oil will bypass back to the pan and not allow oil to go up to refill the res. top up the res and check battery voltage and see if it will fire up
I read on another thread that the high pressure pump has a check valve as well to prevent oil draining out. I pulled my new filter and it is full of new oil so I think at the very least the low pressure pump is working. I looked at the high pressure pump and it is not leaking. How do I prime it to see if I can get the engine to fire?
Remove the plug in hpop resivour and if the level is within a half inch then you are primed.if low then just fill it up manually.if real low then some cranking may be needed but my bet is its just fine.
Ok here is an update. Took the truck to the shop. Bypass valve is still there. Shop checked oil level in high pressure pump,was low so they filled. Then cranked and no pressure no fire. Cranked with cap off high pressure pump and no oil shooting out. So next is to check low pressure pump. Wow all I did was change the oil! Will keep you guys posted.
If there is oil in the HPOP reservoir after you have been cranking the engine then either the LPOP is fine as well or the HPOP isn't moving oil. If there is oil in the res and you're not getting pressure in the HPO system then the problem is likely with your IPR or ICP The IPR is in the back of the HPOP way down in the valley in front of the fuel bowl. You should be able to follow the wires down to it. There should be a tin nut on the back of it to hold the solenoid on. If there is not and you can move the solenoid around on the valve, then it has fallen off and into the valley.
Here is a pic for reference.
As for the ICP, it is threaded into the driver side head at an angle up closer to the front of the engine. You can try unplugging it and cranking the truck to see if it will fire. If it does, the ICP is bad.
Thank you for the information. I will get in to the shop first thing Monday morning and check this. I am getting no oil pressure when cranking. When I pulled the oil filter it was full of new oil so I would think the low pressure pump is working. I will let you know what we find.
If there is oil in the HPOP reservoir and you're not making any HPO then the issue is that for some reason the HPOP (High Pressure Oil Pump) isn't making pressure. Generally that is because the IPR isn't working. Now it could be either that it isn't working (or can't work) for some mechanical reason or that it isn't working because it isn't being signaled to do so electrically (which could be because the ICP is not working). If there is no pressure at all there though, then I tend to lean more toward the IPR than the ICP. If you were making pressure in the HPO system but it wouldn't fire then I would look at the ICP, but since it isn't making HPO at all I think the IPR is the culprit. It could just be stuck too, but that's not all that likely.
ok so here is the scoop. Shop was doing a compression test on the motor and in the process of doing that the engine finally started pumping oil. So we are back up and running. All we can figure is I let the oil drain all night and half of the next day and the pump just lost prime. Tho they did find my turbo is going out so I have a replacement on the way....ouch
I think they had it off when checking compression and glow plugs. Looking at about $1400 installed for a rebuild. Said it had play in it.Bearings probably. They are eagle eyes lol.When inspecting my front diff on my last visit they found a bad cardigan u joint on the front drive line and I have a bearing going out on the front out put shaft in my t case. That only spins when in 4 wd so at least I have some time on that one.
Yeah no kidding. You can rebuild a stock turbo for around $400 so the rest of that is labor and markup. For that kind of coin, there's no way I would have gone with a stock rebuild. Sorry bro, but you're getting hosed!