No start dodge
Presented with hard start/long crank. No codes. Has pressure guage between filter and injection pump. Had 9-10 psi with bouncing needle, with around 40-45 oz at pump cycle. Spec is min 10 psi and 40? oz.Inoperative fuel guage. Has 1/4 tank of fuel. Has engine mounted aftermarket lift pump(raptor?). just sensor in tank. Found no signs of sucking air past lines/o-rings. Has 12.4+- volts at pump and mv. on ground side while cranking. Signs of air during volume test. Dropped tank to replace sender but dropped sender assembly and broke housing so used one was installed with new sender. Tank looks clean inside. Called it a bad lift pump. Replaced filter and all line seals to both pump and filter housing and filter.
After repair I have a no start with 3-5 psi at pump cycle. If scanner left on cycling pump will get up to 15-17 psi. If pump deadhead will get above 20 psi. Volume test 60-70oz.
Called pump support line. Figured another bad pump. Was told pressure deadhead and volume prove pump good. Recommended I put an overflow valve in it. I compared old and new valve blow off pressure and old one popped with less pressure so replaced with no change.
Powered and grounded pins 6&7? at I.P. and still no start. As it had been creating air figured probably ruined injection pump so sent out for testing and was told no codes in pump module but diaphragm is prone to rupture when run with air. So installed new injection pump. No change.
I know it can take a while to get fuel to injectors but shouldn't it show pressure before the I.P. even if injectors empty? Possible to have good readings but bad pump? Raptor wont send me another one due to (good ) readings. I am not a diesel tech at all but owner is a friend of boss so I am stuck with it. Thought I covered my bases but need some help.
Good evening Christopher, Couple quick questions for you before proceeding. Did you go through the bleed procedure for the supply & high pressure sides? You're correct they can be a bit of a pain to bleed. If I remember correctly, the feed line to the injection pump is the lower banjo fitting (a 17 or 19 mm bolt head I think.) Crack that loose and run the supply pump till you have a steady…
Will do in morning. Thank you for your time.
That engine is using the VP44 pump. Those can be a little hard to get started once you get air in them, although they are real easy to bleed. Any time I replace a pump, or need to bleed, I crack open the cylinders 1 - 5 lines at the injectors. They all come loose pretty easy. The #6 is hard to get to, so don't worry about it. Hook up your scan tool and command the transfer pump on. This will…
Thak you. Going to give it a try. Appreciate your time.
Albin that's a great idea to use the transfer pump for the high side bleed instead of cranking. I haven't ever tried that on a VP44. Will definitely use it next time I have one of these. Chris Groff has a great trick involving partial pinch off of the return line for PLN systems following filter replace. I assume it could help expedite hp bleed as well but I haven't tried. I believe the return…