Engine/Transmission (1998.5 - 2002) Lift Pump - In Tank Model, Can I install the Oringinal in-line and have two pumps?

[PBoland]

I bought a used truck with the intank lift pump. The pressure drops to 5lbs at around 2100 RPM. Other than that she runs fine. Can I install a second (standard lift pump) in-line? Has anyone done it. Doe's any manufacturer have a wiring harness available or do I have to wire it in myself. I'm a wizz with heatshrink and solder. I just don't want to go through the hassle it its a waste of time.

 

[MBFARMS]

Yes you can do it. I did it on my truck. All you need is a relay to the stock pump. The only problem that you will run into is the stock pump will have trouble pulling fuel through the intank pump. Eventully the pressure will drop and the stock pump will quit working. My truck did it and my friends truck did it. Save yourself some time and money and go with either the FASS HPFP or a Walbro setup and a Draw Straw II(bypasses the intank pump).

 

[Cummins724]

Get a holley Blue & mount it by the tank. They are good & don't have to drop the tank to install it. In conjunction with the stocker my brother gets 22psi idle & 19 wot with a comp on kill.

 

[mhenon]

Yes you can do it. I did it on my truck. All you need is a relay to the stock pump. The only problem that you will run into is the stock pump will have trouble pulling fuel through the intank pump.

I think you meant to say the stock pump will have trouble pulling fuel "if" the in-tank pump were to fail.

I have the Carter pump mounted on the frame and the in-tank installed by the dealer. The combined pressure was 25psi. I could also turn off either pump (toggle switch in the cab) and still have enough pressure to limp home but the Carter does struggle if the in-tank is shut off. If I turn the Carter pump off the in-tank can hold about 5psi.

Also had to install a bypass valve to bring the pressure down to 15psi as I thought the 25psi was just a little high.

Mike

 

[PBoland]

Thanks for all the feedback. Put the stock Carter in series at the stock location on the motor. I bought the frame relocation kit, but didn't want to cut the fuel line just yet. I'm one of those step at a time mechanics. Once I know everything is fine, I'll relocate the pump. Getting 25 lbs at idle.