97 7.3, will start with extended crank time

[Guinness]

My buddies dad's truck is giving us a hard time recently. Here is a quick run down.

Front main oil seal went bad and was replaced, now truck does not start as quick as it used to.

Died at idle in his driveway 2 weeks later with no start condition, then starts after sitting a dies again. Changed the cps and now takes even longer to crank before it starts (up to 30 seconds or so) but no longer dies and drives normally.

Found the hpop oil tank low, we filled it and it starts alot quicker and still runs fines after it starts. It sits overnight and the tank is empty again, if we crank it 30 seconds it will start or fill it manually it will start quicker.

Changed the hpop (ARM part number) and still have the same long start condition. Checked the hpop tank and it was still filled but air bubbles can be seen coming up (like it still draining but taking a really long time to do so)

The truck is clean and well maintained, please help if you can, I have combed through dozens of posts and cant seem to find anything that we havent checked.

Any ideas on this?

 

[action4478]

May have some junk in the IPR...

Here is some reading on the pump....

 

[roosterdiesel]

The low presure oil pump may be bad. How many miles? Something may have happened when the seal went out or when it was repaired.

 

[Guinness]

We will have to check on both of those. We were down at the dealer getting ready to pick up a new IPR and had it in our hands when we got chatting with an engineer who was there to assist on a 6.0l problem they couldnt resolve. He told us it wasnt possible that the ipr could be an issue, so we didnt end up buying it.

I will have them pull it out and check the o-rings and probably replace them anyway. We found a link on here about a special tool to help take it out.

Any easy way to check the low pressure pump? Once it runs we have good pressure (the sensor is in the hpop reseviour)

Im hoping the IPR is the issue and not the injector o-rings that I also suspect (no smoke when its running though)

 

[Russ]

I'd lean twards the LPOP

 

[Guinness]

Well after driving it for a while it did end up working it self out and starts normally now. It must have been air bubbles from the hpop work we did.

 

[Guinness]

After 2 weeks and towing a 5th for quite a few miles with no problem the truck shut off while idling and the hpop reseviour is empty (bone dry). Oil shows slightly overfilled (because the hpop drained down)

Were running out of ideas other than the new hpop being bad already - its a remanufactured from Ford, the part numbers are correct for the year according to other posts on here I have searched through.

Again, this is my buddies dads 1997 with 7.3

 

[roosterdiesel]

If it ran fine for awhile and then suddenly died with an empty reservoir.....either the LPOP and front cover are worn out or the oil pick up tube for the LPOP broke and now it has no way to get oil to pump. They have been known to crack.

 

[Russ]

See previous post

 

[Guinness]

Ouch, not looking forward to pulling the entire motor out to check those items, is there no way it can be a stuck IPR?