HPOP testing
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5th Wheeling
Joined: Aug 2020
Posts: 33
Likes: 4
HPOP testing
Need to test the HPOP on my truck and I’m not 100% sure on which is the correct way. Was told I could loop the 2 lines together with a T fitting with the high pressure gauge in the middle then was told by another that I had to test each one separate. Just curious as to which is the correct way. I know I gotta cap the heads off when I take the lines lose from the heads. I’m just gonna use my lines that are already attached to the HPOP and hook a gauge to them while cranking it to see what kinda pressure I’m gettin, But again can I do both line’s together or do I have to do them separately? Any tips are appreciated.
I also know I have to apply 12V to the IPR I know the basics of testing it but was talking to some other mechanics and now they got me wondering about the lines.
I also know I have to apply 12V to the IPR I know the basics of testing it but was talking to some other mechanics and now they got me wondering about the lines.
Lead Driver
Joined: Apr 2016
Posts: 7,170
Likes: 1,331
From: Bahstun
0-6000 PSI gauge
its a single pump with two outlets that have check valves, so both need to be blocked
Check it hot then check it when cool
are your injectors leaking at the base while running? That can be a failed oring
its a single pump with two outlets that have check valves, so both need to be blocked
Check it hot then check it when cool
are your injectors leaking at the base while running? That can be a failed oring
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5th Wheeling
Joined: Aug 2020
Posts: 33
Likes: 4
I have the 0-6000 gauge and high pressure hose every thing to test it with. I just need to know if I can do both outlets at the same time. Like take the 2 lines coming from the pump to the heads and loop them together with a T fitting with a gauge in the middle. Can it be done like that or do I do each one separately?
CNCFAB
Joined: Apr 2020
Posts: 4,874
Likes: 2,006
Cap one hpop line, put a gauge on the other and crank truck with the key. Assuming your icp sensor is working (it would see 0psi since the hpop line is not connected to the head) the pcm will command the ipr to close trying to buld pressure, as long as the ipr is functioning properly this will make for an accurate deadhead test of the pump, depending on your findings(and current issue) you may need to then move to deadhead testing each head seperately
Thread Starter
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5th Wheeling
Joined: Aug 2020
Posts: 33
Likes: 4
Cap one hpop line, put a gauge on the other and crank truck with the key. Assuming your icp sensor is working (it would see 0psi since the hpop line is not connected to the head) the pcm will command the ipr to close trying to buld pressure, as long as the ipr is functioning properly this will make for an accurate deadhead test of the pump, depending on your findings(and current issue) you may need to then move to deadhead testing each head seperately
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5th Wheeling
Joined: Aug 2020
Posts: 33
Likes: 4
It dies when it’s warmed up but while it’s cold. The ICP is idling at 500-600 psi and the IPR at idle is 15-18% WOT IPR will only do 38% and ICP will go to 2400+ psi. After it gets warm and doesn’t start back, Crank No Start, readings are ICP 280psi and IPR is 55% while cranking it.
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CNCFAB
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Lead Driver
Joined: Sep 2002
Posts: 9,476
Likes: 2,009
From: North Texas
15-18% at idle? Wow. My old pump was around 12-13% at idle, did like 60% at WOT and could not hold rail pressure with stock sticks and a small tow tune.
Anyway, curious what you find with the testing. One of the best things I did was a fresh HPOP.
Anyway, curious what you find with the testing. One of the best things I did was a fresh HPOP.
Tuned
Joined: Jan 2020
Posts: 338
Likes: 112
From: Southern California
It dies when it’s warmed up but while it’s cold. The ICP is idling at 500-600 psi and the IPR at idle is 15-18% WOT IPR will only do 38% and ICP will go to 2400+ psi. After it gets warm and doesn’t start back, Crank No Start, readings are ICP 280psi and IPR is 55% while cranking it.
I ended up pull the IPR and one of the orings was damaged. Bought a rebuild kit and fixed the problem.
while I had the old IPR out I tested the electrical connector too.
This issue of starting when cold but not hot was a frustrating one for a bit for me.
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5th Wheeling
Joined: Aug 2020
Posts: 33
Likes: 4
Truck starts when cold but takes a little bit of cranking to start it, it build’s pressure slowly and the dirt cycle % goes up like it’s supposed to but the scanner show the ICP at 1000+ while idling cold and duty cycle is 20-25%. Again after it warms up and I shut it off it doesn’t start back, haven’t tried with a mechanical gauge yet on the Hpop or air test the injectors yet. The ICP does drop down to normal pressure when warm too according to the scanner.
Lead Driver
Joined: Sep 2002
Posts: 9,476
Likes: 2,009
From: North Texas
Efuel it and never look back.
Best thing I ever did to my dually. More power, superior filtration, easier service, etc. Search from posts from @fordman67 he has tons of data from pre and post efuel.
Best thing I ever did to my dually. More power, superior filtration, easier service, etc. Search from posts from @fordman67 he has tons of data from pre and post efuel.
Tuned
Joined: Jan 2020
Posts: 338
Likes: 112
From: Southern California
I replaced my mechanical pump with riff raff motorcraft. I notched a box end wrench to get a better bite when tightening the banjo bolt. I was able to remove the banjo bolt without the notch but couldn’t get a comfortable angle to tighten without the notch with the delete EBP valve pedestal. Since I was disconnecting all the hoses, I decided to replace them all along with the recommended banjo bolt gaskets. Fuel bowl/FPR comes out and it’s a great time to clean and rebuild it as well. I replaced all orings, fuel heater (because it was damaged). Also a good time to replace or delete the fuel restriction sensor, I chose to replace it. I put an upgraded FPR spring and new schrader valve. I figured if it is coming out might as well replace/rebuild as much as possible, IMO.
