95' 7.3 hpop is empty, if i fill it will run just long enough to empty res. then die, replaced the lpop and still have same problem. oil pressure gauge on dash shows no pressure during cranking, or when i get it to fire by filling hpop res. what am i missing?? any help would be appreciated!

 

No visible leaks? No oil getting to the Hpop? If you tested the low pressure oil pump, and it's fine then you might have a blockage or an internal leak? Interesting? What does your dipstick say?

 

has no external leaks, i'm about 3 qts or so overfull (from manually filling hpop res.). going to pull cover off res. and look for oil flow to it. i can;t see anything through the tiny inspection hole.

 

Hmmm... I wonder whats plugged up? Or worse a crack internally? one crack in the HPOS and no pressure! Remove and inspect the reservoir.

 

i did remove it and had a guy crank it over while watching for oil to shoot out, i was disappointed to see no oil shoot out. Oil was level with the port, but never changed during cranking. Although after cranking did notice a lot of air bubbles come up. Repeated this several times with same results. I'm thinking broken pick up tube. thinking about overfilling crankcase to point of pick up tube height and trying then. not sure how much oil that will take. Any ideas??

 

Keep digging take a look at the pic up tube. We need to find out why you'r not getting oil. I don't have any answers for you. So Please forgive me. Glad to now you'r mechanically inclined, other wise I would be looking up my data base for a shop in your area. It's not easy to diagnose a problem on a vehicle unseen. I also apologize that I have been the only one responding to this thread. We plenty of talented members on here, so I don't know what to tell you.

 

I would first want to know if that LPOP is doing its job. I know it says you replaced it, but it's obviously not filling the res. If it runs when filling it, everything dowstream from the HPOP is doing its job.

 

Need to check the pressure of the lpop and seen if its flowing any oil. You might have cracked the oil pickup in the pan.

 

thanks for all the help, the lpop is not producing any pressure, and have determined the oil pick up must be broke. the engine R&R it takes to confirm exceeds the time i have to spend on it for awhile. will post with final diagnostic when i reach that point. again thanks for the help and the ideas.