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Mopar1973Man

Common Rail Vs. VP44

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Looking at the failures of the common rail system which happens to be the injectors most cause by honing from debris that passes through a small orifice inside that cause the it not to seat properly later in life. But still in all I've seen prices ranging from $300 and up per injector for CR truck for a total of $1,800 for a set of re-man stock injectors. Then looking at the VP44 which happens to be the failing point of the 24V Cummins. with the failure of a VP44 based on the fact of lack of lubricity and low fuel pressure that kills them. They only happen to be now $1,100 bucks for a new pump. In either case in stock form I've seen both trucks fail just as quick but of course the CR injectors are more expensive... So what to do to protect what you got? Well the common story that seem to be sung by all shops, dealers, etc is good clean fuel. Most suggest you upgrade from the factory filter 10 micron to a 2 micron if possible. Then in both cases it good to meet the minimum pressure requirement for the CR is 9.5 PSI for the VP44 its 10.0 PSI.Another personal suggestion is a shot of fuel lubricant of some sort. (2 cycle oil, bio-diesel ,etc) In any case the CR engines have a CP3 pump which I got to admit is better that a VP44 but doesn't mean its excluded from the wear list. This pump is only fuel lubricated so if the fuel lubricity can keep up then it starts to wear. But think... There is only a edge filter before the injector... But that doesn't seem to take care of the problem. I better stop now and listen to the other comments...

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Yeah Mike, those parts are expensive!!!!!:2cents::2cents: I've changed the CP3 on my truck. It started leaking......the seals went. That's what you get when you try and make half the pump aluminum and the other steel!!!!:cookoo: Believe it or not, for a brand new remanned pump, only cost $650 w/core from "The Diesel Store!!! It's a PITA to change out because of where it's located, but it's not difficult. The only real bugger about it is making sure you don't drop the CP3 nut or washer down into the front cover!!!!!!!:cry: If you do that, you've got a bigger job to do. Since I've replace the CP3, I have this metallic tapping once the engine warms up. I've done the research on this, and it's a gear lash caused by the piston strokes of the engine and CP3. The fix is to pull the CP3 gear and rotate the engine 30 degrees and put back together. It may take a time or two to find the sweet spot though. It's not a timing thing as it's more of a "phasing" of the piston strokes of the engine and CP3 to avoid the gear lashing sound. The tapping doesn't real cause anything accept unneeded wear.....which is minor at best. As far as FP to the CP3, my Walbro is pushing 25-30psi depending on the ambient outside air temp and how the truck has been running. It's probably less than that at the CP3 though because my sender is pre fuel filter..........and I have a 7micron filter in the OEM housing and a 2 micron filter from GDP plumbed in after that. I don't know the drop across the filters though. My fuel pressure is higher than others because Richard Martin from GDP set the regulator at like 22psi or so when he was selling his Walbro fuel systems. The CP3 can handle almost any pressure you throw at it unlike the VP. Actually at about 60psi, you'll crack the plastic top on the OEM fuel filter housing!!!!When my injectors go South, I think I'm gonna get some 40hp F1's or the mileage max ones. I know that Don M is a piece of work and difficult to deal with, but he's the best. Besides, his injectors are cheaper that getting them from DDP. The F1's for six cost $1100..........and Don does his magic to all the injectors there. Flow test, hone etc. Hopefully I won't need them for a while. I've got 115,xxx on the clock now and she's running good. Got a couple of minor issues that I'll post in another thread.

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