Truck won't build ICP

[JD3020]

So i got bored last night and since i have a massive pile of parts here ( Hydra, T4 mount with 468, some DIY HPOP stuff, and a few other things) i decided to put my 17* pump on. I pulled this pump off my project engine, i personally drove the truck before i pulled the engine out and it ran extremely well. Last time it ran was early-mid spring. Got the engine home and on a stand 4-5 weeks ago and i pulled the HPOP out then, its sat in a plastic bag on my bench since.

So last night i pulled my truck up to the garage to tear into it, truck was running like normal. Swapped HPOP's, re-used my old IPR, and had it cranking in about an hour. But thats as far as its made it. It cranked, and cranked, and cranked some more. Commanding 88% DC(IPR closed) but its only showing about 33psi on my scanguage. I have oil in the res, i've cracked the lines and plugs and i'm getting some oil to them as well. But it will not build any pressure. I've tried a couple IPR's. Cleaned and inspected everything the best i can, and i don't see any oil leaks. It honestly feels like i've been cranking this thing longer than i did when i was trying to get this engine going last winter, after i had it all tore apart on a stand and went through it.


The only "odd" thing about this is i used a Fel-Pro HPOP gasket as i had one laying here, not sure if maybe the gasket has failed and allowing a HPO leak at the front cover, which IDK if thats even possible. Just has me scratching my head as i've done a couple HPOP and IPR swaps, put an engine in it, put in 4 different set of injectors, and this is the first time i've had an issue getting it fired up.

 

[Arisley]

Did you remember to plug in the IPR?

Just kidding, sorta. Sometimes it's the little things that get us.

 

[JD3020]

Haha, i wish it could be that simple. IPR has been plugged in. The little metal plugs themselves are somewhat loose inside the plastic body, but i don't think that would be causing me an issue. All the wiring still looks good and feels pretty tight in the connector.

 

[Barnbuilder]

If the wires are touching inside the IPR plug it will not start.

 

[JD3020]

Wires aren't touching in the plug from what i can tell.

Is it possible for the pump to airlock?

 

[co04cobra]

Are you filling the hpop res. from top or will it refill while cranking?

 

[JD3020]

It refilled on its own almost instantly, and the level has not dropped at all.

 

[co04cobra]

What year is the hpop from?

 

[JD3020]

Its off a 2000 T444E. My engine is a 97 from what i can remember, pretty sure the date tag on the front cover and valve cover said 97 before i stripped and painted everything. So i don't think there should be an anti-drainback issue.

 

[co04cobra]

Any chance the fel-pro gasket could have been for the wrong year? When you disconnect the lines at the heads and crank it over, how much pressure is there?

 

[JD3020]

It came with a timing cover gasket set i have, label says 96-99 7.3. I did not compare the two gaskets side by side though.

When i cracked the lines i was getting some oil, but it wasn't spraying out like it was under pressure. Just sorta running out.

 

[co04cobra]

Gasket could be worth looking at. However, I've had this happen to me once or twice. Pulled hpops off running engines and put them in storage. Then when I installed them after sitting for awhile anddddd no start.

Same as you describe. No oil to the heads for some reason. Changed pumps and it solved the problem. I don't know what happened for sure on those 2, but I just assume, one of the pistons sticks from sitting.

 

[mandkole]

aside from IPR moving oil to drain, x2 on gasket and check gear for torque..

 

[JD3020]

I havent been able to get my torque wrench yet, but i got the bolt as tight as i could. Currently out of town but i hope to get the pump off tomorrow and see whats up.

Any way i can bench test or inspect the pump myself?

 

[JD3020]

Well the new pump is off, the FelPro gasket is identical to my old gasket so no issue there. And it spins just as freely by hand as my 15* pump does. Now to throw the old **** back on and pray it runs.

 

[JD3020]

Old pump is back on, no change. I guess next up is to deadhead the pump and see if it builds pressure

 

[TARM]

My bet is its the IPR valve. I have seen this reported numerous times by people upgrading to a new HPOP and swap the old IPR. Did you by chance replace the oring on it ? Not sure why but that has cuased people a number of issues but still others the IPR when swapped just seemed to pick that time to fail for whatever reason.

If you look at everything you have gone thru its really the only part you touched that could create this issue. Unless a few injectors took this moment to have their orings fail or a oil rail plug to unscrew itself the IPR would be where my focus was along with the ICP sensor. But if the IPR is saying 88% DC and you know for a fact the 15 degree pump was working and you just took it off my guess is the IPR is not closing much at all.

At the very least pull it out and break it down and check it for being clean etc..

Best would be if you had access to another IPR and could test.

 

[JD3020]

I've tried multiple IPR's with no change.

Once i get some time later on i'm gonna dig out the multimeter and start going through the entire engine harness. Only thing i can think of is i'm not getting voltage to the IPR.

 

[02BigD]

Have you tried cranking it with the ICP sensor unplugged?

 

[JD3020]

Yes, shows crazy ICP as it should, and still running DC up to 88% but no change.

What is the proper way, and specs on testing the voltage to the IPR? With KOEO, one lead on the negative battery terminal, i'm getting 12-13v at the red IPR wire, and around .5v to the yellow wire. DC is 14.8%, which i believe is right where it should be KOEO.