ok i think you guy remember my last thread, iv had my truck on the charger now its cranking over fast iv got a new fuel filter and the bowl filled with powerservice. its cranking over fast tach is comming up to about 200 rpms, no smoke and the oil presure gauge reads nothing no matter how much i crank, checked the oil leval in the crank case and its full

 

Have you checked the oil level in the hpop reservoir?

A lot of cranking without starting will sometimes drain it faster than the lpop can refill it.

 

I'm no where near as smart as some of the people here but have you checked the HPOP?

 

i have not checked the hpop res, but where is the presure sender for the oil presure gauge, seems like it would indicate oil presure before the oil even got to the hpop, normaly when i have to give it a few extra cranks to fire up the oil presure gauge will jump up before it starts

 

The pressure sensor is on the top right of the hpop reservoir and the plug to check the oil level is on the top left. If the reservoir is low it won't indicate any pressure on the gauge.

 

filled the hpop res and it fired up, was running real rough but was running let it run for a quick min then shut it down ill drive it over to the shop tomorrow and get my new block heater cord on.

 

oh i forgot to mention while it was running i had an cel, will scan for codes tommorrow while i have the truck in our shop

 

you still have to crank the **** out of it for it to start, still air in the system? new block heater cord is on but dident get around to scanning it for codes when i started it today it ran smooth and no cel, but have to crank the **** out of it every time for it to start

 

Could be air in the system if it hasn't been run long enough....for an hour or so.
Check the HPOP level before starting it just to be sure it's not draining down.
You may have a check valve (short circuit) hung up.

Check valve picture

 

Sounds to me like there is air in the system. Your CEL im sure comes on for low HPOP pressure. Once you get it started I'd let it run or drive it, but make sure the oil pressure gauge comes up before you drive it or let it run for a long period of time, if you dont then your gonna have some more problems then im sure you want.

Cowboy Steve

 

It doesn't matter what the gauge shows. If there is not enough oil pressure the engine will not run. If you loose oil pressure the engine will shut down before any damage is done.

 

Kinda a catch 22, most cases your correct but not all the time.

1. Your gauge can show no pressure but the truck will still run. I had it happen to me when my HPOP was going.

2. The engine can run if oil pressure is lost and damage can be done as a result. Seen it happen..... However I've also seen the engine shut down like you said before any damage was done. Goes both ways

Cowboy Steve

 

please explain to me how a heui system can run if the low pressure pump is not feeding the high pressure resevoir? yes, it will run briefly but if it were under a load you would only have mere seconds, if that.

 

(1) Well of course the gauge can show no pressure and still have the truck run, That's exactly why I said:
All you have to do is unplug the wire from the top of the sending unit and you can prove that.

And your hpop has nothing to do with the idiot gauge on the dash.


(2) They will not run with no oil pressure, and you've never seen it happen.

 

Correct.

Cowboy Steve