Can anyone clue me in to what models/years were having problems with the lift pumps? Is this something that Dodge has fixed with the new models?
Just bought a 2006 2500 Quad Cab 4x4 this last weekend. 250 miles and still looking forward to breaking this thing in! Speaking of which... what advice does anyone have to properly break this in? Can't tow anything as I haven't bought the boat yet

 

Dodge believed that many of the failures were because the pump was pulling fuel from the tank instead of pushing it out of the tank. So, starting with the '05's they put the pump in the tank. Many an injection pump failed because of the lift pump failing. My lift pump failed at about 30,000 mi last month, and the dealer installed the new pump in the fuel tank, like yours has it. I was lucky that the lift pump failure did not affect the injection pump......YET!
As for break-in, read your owners manual, it's short and sweet abou the subject. Note that many a rig take 20,000 miles to fully break in.
Cheers
Mike
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what was killing the injector pumps was back in the VP44 day the pump was actualy lubricated by the Diesel fuel itself. the CP3 on these HPCR engines is not. it is mostly lubricated by engine oil. If the Lift pump dies it will not effect the pump as much. yes the vanes will run dry, but by that time the engine will most likely quit from starvation.

 

Actually:

Yes, the in tank pump has replaced the failure prone engine-mounted pump...and while it might seem good, it is bad for the VP44 as the VP44 needs 14psi ideally...most intank pumps are not holding 8 psi at idle and pulling down to 0psi at WOT...this can cause the pistons in the VP44 to develope fractures and ultimately fail. As far as that goes, I don't see where this can be good for the CP3 either...

Regardless, both the VP44 and the CP3 are fuel lubricated...the only difference is that the VP44 is electronic and the CP3 is mechanical...the VP44 pressurized each injector, the CP3 simply increases fuel pressure to the common rail.

IMHO, if you have a 24-valve CTD, a fuel pressure guage is needed. A lot of guys are adding pusher pumps to their existing in-tank pump or replacing the in-tank completely with something like a FASS to keep the PSI in the optimum range...which from what reading I have done is still 10psi for the CP3.

And before someone starts throwing out "it is a volume thing", think about this...if you are pulling a guage down to 0psi, you can't see what you are pulling as vacuum (below 0 psi)...pulling a vacuum on the guage means there isn't enough volume feeding the IP...this is just for the CP3...the Bosch requirements for the VP44 are 14 psi minimum.

steved

 

If I had to be really specific.....i'd say ALL years so far!
Mike

 

Why this statement? The 12-valves with mechanical injection pumps and mechanical lift pumps rarely had any pump issues...these are the 1989 to 1998.5 trucks...the lift pump/injection pump issues only came around with the intro of the 24-valves...

steved

 

The Bosch P7100 and Bosch VE models used in the 95-97 and 89-94 Cummins motors had plenty of failures and shortcomings. They only maxed out at around 14000 psi, they didn't react as quickly to changing engine conditions(because mechanical systems are just less precise), they suffered from low or no pressure situations because like todays systems they relied on fuel(as well as oil P7100) for lubrication. The 12 valve motors weren't designed to handle the higher levels of Hp todays' motors produce. They had an architecture (internal parts setup, such as piston shape and rod strength) that was not designed to go much beyond the 200 or so Hp originally intended. When pushed to deliver higher Hp both the P7100 and the VE models both wore out much faster. See Diesel World Magazine Vol. 1, No.1
Spring 2006 Page 95 to confirm these facts.
Always......No, Never forget to check your sources!
Cheers steved
Mike
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The common rail motors ('03 and up) are light years ahead of the old and rock solid 12 valves.

 

Ah, but you said a very KEY word...pushed. In a stock setup...the mechanicals have very few failures. I don't even consider the BOMB'd trucks because they are being pushed outside their designed limits...anything pushed over it's limit will fail at some point...as far as I'm concerned, if you had a failure in a BOMB'd truck then you have no reason to whine because YOU caused the failure.

You are comparing apples to oranges.

steved

 

I'm not going to argue this one steved. Just providing factual info to a member asking a question. Thanks for the input though, your opinion counts too.
Mike