PLEASE HELP.. REALLY LONG CRANK TIME!

[dieselkane]

Hey guys I am working on a 96 F250 7.3, I have done so much to this truck and usually can figure out problems. This one has me stumped!

I replaced the IPR, the IPR harness, all new Injector O-rings. It will start, and when you get on it on the freeway, it screams like it has all the power in the world. Runs perfect on the freeway! At idle though, it runs a little rough.

If you let it sit for just a minute, it will fire up pretty quickly. The problem is when you let it sit for 20-30 minutes or so.

You can crank and crank and it takes forever to build back low pressure oil. Eventually after cranking forever, the oil pressure gauge moves to the middle, and the truck will start up.

Again, runs amazing after getting it started! High pressure oil reservoir is full.

I'm thinking LPOP, PLEASE HELP!

[STROKED_NY_023]

LPOP, Fuel pressure, fpr screen??

Sent from my Galaxy S2 while my wife is yelling at me for being on my phone...

[dieselkane]

Originally Posted by STROKED_NY_023

LPOP, Fuel pressure, fpr screen??

Sent from my Galaxy S2 while my wife is yelling at me for being on my phone...

Went through fuel bowl completely, cleaned everything, changed o rings, truck makes good fuel pressure. If it is the lpop, wouldn't it have problems running all the time? There are no issues when the truck is warm and you are driving it on the highway.

[BigFuel]

After letting it sit for a while spin off the reservoir plug (across from the oil pressure sending unit) to the HPOP and look inside. Is there oil sitting near the top or is it gone?

[dieselkane]

Originally Posted by BigFuel

After letting it sit for a while spin off the reservoir plug (across from the oil pressure sending unit) to the HPOP and look inside. Is there oil sitting near the top or is it gone?

After it sits, and doesn't want to start, the HPOP reservoir still has oil right up to the bottom of the plug. It seems as though the reservoir always has plenty of oil. The HPOP tests out great with a mechanical gauge. When it doesn't want to start, and you have to crank it excessively, the oil pressure gauge on the dash will read low with tons of cranking. Eventually the truck will finally fire after cranking the piss out of it, and the oil pressure gauge jumps up. This thing is stumping the hell out of me!

[BigFuel]

Did you do any work right before this issue started? You didn't happen to take apart the oil cooler or install a secondary oil filter system? In the oil filter housing above the filter there are two plugs. The left one is if you want to hook up a oil pressure gage at the oil filter. The right one has a check ball and spring in it and allows the oiling system to bleed off excessive pressure as it runs. People that have opened the left plug have accidentally not reinstalled the parts in the correct order and the truck is constantly bleeding off oil through this port back into the pan.