Got the gauge hooked up as I type and so far I've seen 700psi idling cold and it's dropped to about 500psi hot idle.

What should I see when I take it for a drive here shortly?

 

It will vary by load, throttle position, demand. etc. WOT can be somewhere between 2400 and 3200. cruise will be low 800-1500. idle sounds about right. what it holds at extended WOT with your maximum tune vs what it holds at extended WOT in stock tune is the big question
Barney

 

What about 1600 when I stick it on the limiter while in park and idle. Stumbles it *** off too!

It refuses to rev clean!

 

not good. one of the OEM tests was to hold it at the rev limiter for 10 minutes while monitoring pressure. should hold up and not drop below 2800 IF I Remember correctly. If you're only getting 1600 you've got a leak somewhere. O rings, or internal something.
how's the LPOP hold up? with 300K plus miles it may be having trouble keeping the hpop full.


Barney

 

I'm R&Ring the LPOP when the rain stops. Well see then what it does.

I just got some low and high press gauge defile made and was monitoring it.

 

Pressure at idle is usually right at 500 as mentioned above, you may see a little higher when cold but pretty close to that. Depending on the truck and the load you will see a big variance for pressure. A strong HP oil system will show 2800-3000 when loaded hard. A weak system may only show 1900-2200. Average is 2200-2800 and it has been said that most trucks fall in that range. Again it is hard to compare as the real measurement is from your IPR duty cycle. If you are pulling 2800 psi at say 42-45% you have a healthy system. If you are seeing 60-65% DC you may have issues. From all the trucks I have tested anything under 50% is normal, sure you may see a spike above that for a second, but not constant.

Idle IPR DC will be roughly 18% cold and around 10-12% warm.

 

[I have a 97 7.3 that won't even hold 500 at idle and the highest reading I've seen is about 2200-ish Max psi WOT with a car on a trailer. It barely hold 75 mph hauling.
AE readings from my laptop while driving. I assume my HPOP needs rebuilt then?


QUOTE=bfife;10773410]not good. one of the OEM tests was to hold it at the rev limiter for 10 minutes while monitoring pressure. should hold up and not drop below 2800 IF I Remember correctly. If you're only getting 1600 you've got a leak somewhere. O rings, or internal something.
how's the LPOP hold up? with 300K plus miles it may be having trouble keeping the hpop full.


Barney[/QUOTE]

 

What are your IPR DC readings at these pressures?

 

And can you measure fuel pressure?

 

Yeah that rough choppy rev is likely air in the hpo or the fuel.