2nd Gen Non-Engine/Transmission Issues with fuel pressure gauge

[DNewell]

Well, I'm guessing someone out there can help me. I just bought a Autometer Ultra Lite fuel pressure mechanical gauge with the isolator and I'm not too sure how to hook it up to my truck. I read in a Haynes manual to take two of the caps off of the fuel filter and I can use that. Does anyone know if it will work with only taking one off? I tried, but I kept having problems starting my truck. Something about no fuel pressure as well. I would have to actually add fuel to the fuel filter to get it to run again, I think there was a air lock or something going on. Does anyone have experience installing this fuel pressure gauge with the isolator onto a 1998. 5 and newer 2nd gen truck??? Please help!

 

[DNewell]

I've got a 98. 5 2500 with 24valve motor. Now, by indicating cracking the fitting on the VP44 side, do you mean right off of the fuel filter? I was fiddling around with the fuel filter and I drained a bundle of fuel through the fuel/water separator and then the truck wouldn't start. After messing around for awhile, I just took a syringe and put fresh diesel directly into the filter to get the thing started. I'm now curious as to whether my lift pump is going bad... The antifreeze side of the gauge is completely full, I did that last night, but then I had problems starting the truck. I also clamped off the fuel line going into the lift pump so there's no backflow. I remember seeing something about doing that in the Haynes. I'll try cracking the line off of the fuel filter to the VP44 and re-installing the gauge w/isolator to the one cap location. I'll update tomorrow or tonight. Thanks!

 

[Rattlin_Ram]

If you HAD to put fuel into the filter to get it to start it would seem to me the lift pump isn't moving any fuel. Did you try bumping the starter to run the lift pump and fill the filter canister?



Just had to change out a lift pump last saturday on a friends '00 CTD. He called me and asked why his truck was stumbling when he put it to the floor. I took a new fuel filter out there to check that first, and after putting in the new filter, couldn't get fuel to the filter via the lift pump, even though you could hear it running. $180 later, and thanks to the local Cummins dealer we had it up and running. And according to him with more power than it had before (obviously it had been out for a while). He's lucky so far, no codes or anything to indicate the VP-44 is on it's last leg... .

 

[DNewell]

Yeah, I'm thinking it's my LP. I think that by filling the filter bowl with fuel, it's creating a vacuum that allows the motor to run, but outside of that, it's not really supplying much pressure. I don't really know about the power issue. The truck appears to have good power, but it does lag a little bit when shifting into higher gears, ie. 2nd to 3rd. I just plopped down 160 for the fuel pressure gauge, and now have to do a LP... Sounds like VISA may be getting some more money...

 

[DNewell]

Yeah, I'm going to go get a new LP most likely tomorrow. I don't have the time tonight, and I think it's going to be a real pain to put it in, but I think that it needs to be done. I want to make sure I don't torch the VP44. I hear that's really expensive. I'll change out the LP tomorrow or on Turkey Day and then I'll repost to let you know what I come up with. Thanks for the help for a newbie Cummins owner. I just love my truck(I've only had it just over 2. 5 weeks) and I can't wait to see how she runs with good fuel pressure.

 

[Rattlin_Ram]

LP is pretty easy to change out. Just a tight sqeeze. A second set of hands really helps, if nothing else to hold wrenches, and the light while you have both hands down in there getting the banjo's back in place...

 

[JKinney]

I just bought a spare lift pump(new) on ebay paid 96. 00 hes gottem for buy it now 100. 00

 

[DNewell]

Yeah, I just picked up a LP from NAPA for 170. Very comparable to Cummins, and made by Carter(I was told). If I had a third arm, it would be very helpful... Going to be a tight squeeze and I think that a lot of cussing is in order, but I hope it works... With any luck, I'll have it in tonight, but that's only if my infant is cooperating.

 

[JKinney]

Pull the bolts on the fuel filter and move it off to the right and the fuel pump is right there, I think I can pull the swap and prime in under 20 minutes.

 

[DNewell]

Well, I got the new lift pump in and that was the problem all along... I also got the pillar pod in with a FP gauge in and it works sweet. On my 98. 5 24 valve it reads about 12 psi at idle and drops down to 8. 5-9 at WOT, but I didn't hold at WOT for very long. Seems to idle smoother and all works great. thanks guys for all your help. The only thing that I don't like is that the LP studs are screw out studs, and the old ones got stuck on the plate. Took me three times as long getting these out. Aarghhh!!!

 

[JKinney]

Take a look at the vulcan big line kit, my fuel pressure does not drop below 12 psi underload.

 

[DNewell]

Where can I find some information on the big line kit? I'd be interested.

 

[JKinney]

at vulcanperformance.com

 

[DNewell]

My question would be, couldn't I piece this together from parts from a local shop? I'd have to do a 90 degree bend off of the LP, but outside of that, the rest would be relatively easy. I basically did the same thing when I ran my isolator to the FF plug. I just put a 1/8" NPT fitting with a 1/4" nipple on the FF canister and ran this to another fitting on the isolator. Just using 1/4" rubberized fuel line and the clamps. I'm thinking I could find some larger fittings for all the other locations of the banjo bolts and install rubberized tubing. Since the FP is not over 15psi, the rubberized tubing should be okay, right?

 

[JKinney]

You most likely could. Vulcan supplied 1/2" fittings for the vp, fuel filter and one 1/2" for the pump. he supplied a 3/8" for the pump inlet. He supplied a bracket to move the pump to the frame, he supplied all the hose and a wiring harness extension. He also supplied hose clamps wire ties and instructions.