Engine/Transmission (1998.5 - 2002) Tandem Cummins OEM Lift Pumps

[Creed]

I've read some lift pump threads and I'm wondering if anyone has tried two Cummins OEM pumps in tandem; one on the engine, and one on the frame (w/ relocation kit)? Can both pumps be wired in parallel from the factory harness?



The reason I ask is because I have my spare pump sitting on the shelf in the garage. I figure it would better serve mounted in the truck helping the engine mounted pump.



The BD tandem kit (uses the Carter P4601HP) looks intriguing. How's that working for those who have it?

 

[michaelteders]

tandem pumps

i'm running a carter 7 psi pump in series with a pusher off the tank 15 psi 100 gph the oem mounted one is wired into factory wiring and the frame mount is run by toggle and relay

I flip the toggle after engine is running have not had any problems with this setup also the dealer tested the flow it was over twice what was needed

hope this helps



mike

 

[GeneA]

I just had the carter kit installed in tandem with the oem. Before I was getting zero pressure under load with a new lp and new replacement inj pump. So far good pressure under load no codes and at 23k gcw it just ran sweet.

 

[rweis]

Gary has a setup on the frame that if the primary lp fails the secondary one starts and bypass valves open and the secondary lp feeds the VP44.



Very automatic, very automatic backup



RASP does the same with a pressure switch to turn on the backup.



Most all of these BOTH pumps are on the frame because of the distance from the tank and verticle lift where the OEM lp is mounted on the engine.



Bob Weis

 

[ELaslo]

Gary-K7gld. . Looks like a good setup. Creed, you might want to check out his posts. Impressive

 

[V-Metalworx]

I have two carter pumps on my truck for about 2-years both of whitch are wired to the factory plug and I've had no problems It used to be hard to start when it was hot have about 22-25psi at idle my truck was a 2000 but we put my friends smarty on it and it puts all the updates in the ecm even after you put the stock progam back in now then when I turn the key on the pumps just run for a second that fixed my hot start problem was gonna up grade to a fass system but not untill one of my pumps dies If it aint broke don't fix it