Engine/Transmission (1998.5 - 2002) Question on Fuel Pressure gauge install

[GIT-R-DONE]

I got a question on the Dipricol Fuel pressure gauge. First I lost the instructions to the gauge install so I came here. Should you bleed off the air from the fuel line to the isolator? Or are you supposed to leave air in the line. Also, are you to bleed off the air from the top side of the isolator that goes to the gauge? No, problem installing the antifreeze on the to of isolator but am not sure about bleeding off the fuel side. Thanks in advance



Don

 

[dieselsam59]

i installed the 18" hose from genos and bled it where it screws on the diagnostic port. i did not bleed the gauge side. Gauge works good but lp bad

 

[JPLB22]

I have the newer white face, green light Dipricol FP gauge. When I first installed I had the isolater on there and did not bleed either side of the isolater.



But I did have a problem with the isolater. I'm not sure exactly what it was ( it was the billet isolater ) but I think the diaphram was stuck. My pressure would only go to 5 psi. Once there it was rock solid and it would take half an hour to fall to zero after the truck was shut off.



So I decided I didn't need the isolater. I used the clear antifreeze hose and blew it out with compressed air, put a 1/8 NPT fitting on it and ran strait diesel to the gauge. Been happy for the last 9 months.



Since I have the clear hose up to the gauge, I've noticed that after a fuel filter change or LP change or any time the system looses pressure, for the next day or two after every shutdown the fuel drains back away from the gauge. So I don't think bleeding the fuel side makes any difference.



Jeff

 

[jhoughton]

I just insalled the same gauge. As per the instructions you need to mount the isolator horizotal and bleed the air from the fuel side through the bleed screw. Then fill the other side with anti freeze. If the clear line is not over 3 feet then bleeding the line is not required. I also used the 18 inch line from geno's. Mine works great so far.

 

[Sixpack]

I didn't bleed the air out of either. I did have to fill the isolator up with anti freeze though. Works great! As said above, you need to mount it horizontally. Good luck, Phil



https://www.turbodieselregister.com/forums/showthread.php?threadid=91432

 

[DLausche]

I don't think bleeding on the fuel side of the isolator is needed. Any air in there will compress quickly and the end result is the air psi will be the same as the fuel psi. The gauge side of the isolator is a different story though. The gauge side is a sealed system. Air on that side will compress the same, but that means that the isolator diaphragm will need to deflect extra in order to compress any air on that side. Probably not a problem with a large diaphragm isolator and a narrow line to gauge. At a minimum thought the isolator should be filled with antifreeze.



I ended up bleeding all the air of of the gauge side of my DiPricol. Used a dispenser that you get with kids liquid medicine. It's like a syringe without the needle on the end. Stuck a 2" piece of small diameter tubing on the end that is flexible enough to fit the dropper and also onto the 1/8" gauge line. The dropper can be used to put antifreeze into the tubing and also can be used to suck air bubbles out too if so desired. I probably went overkill by getting all the air out on the gauge side.



Good luck with your project.



-Deon