Any reason I would have 2 lift pumps?

[rodent]

Trying to undo any botched mechanic work on my M1008 and this is one I can't figure out. Why would use 2 lift pumps? Both fuel pumps come on when key is on.

I was going to remove the smaller one on the right. Just wanted to check to see if you guys seen this before or if there's any reason for 2 lift pumps. Also may relocate it down on the frame somewhere instead of the wheel well.

 

[patracy]

No need for two. Although the one on the left looks like a carter pump, which was problematic on the Dodge trucks (civy) with a cummins.

 

[rodent]

No need for two. Although the one on the left looks like a carter pump, which was problematic on the Dodge trucks (civy) with a cummins.

Yes it is a Carter. Maybe I should replace both with one good pump. I need to read up to see what guys are going with on lift pumps. Thanks!

 

[patracy]

One on the right is what I run on my CUCV. As well as my Liberty CRD.

 

[rodent]

One on the right is what I run on my CUCV. As well as my Liberty CRD.

Looks like what the newer 6.5 trucks run. Similar to the ACDelco EP158. Maybe I should run that alone and try it first before spending more $$$. Thanks.

 

[patracy]

Runs just fine on mine. And I've turned up the fuel and added a turbo.

 

[doghead]

Those rotary pumps used to be the "thing", when pulse type pumps were not so common and inexpensive.

Any idea what the problems are with them, in general?

The pulse/inline pumps are inexpensive and fairly simple.

I have them on a few things.

 

[rodent]

Those rotary pumps used to be the "thing", when pulse type pumps were not so common and inexpensive.
Any idea what the problems are with them, in general?
The pulse/inline pumps are inexpensive and fairly simple.
I have them on a few things.

I'm curious too. Also what is the electric pump most owners use for the lift pump. Just want something reliable. I would think the 93 6.5 pump would be reliable.

 

[patracy]

I'm curious too. Also what is the electric pump most owners use for the lift pump. Just want something reliable. I would think the 93 6.5 pump would be reliable.

The carter rotory vane pumps have a high failure rate with the 2nd gen Dodge 24v (VP44) cummins trucks. So much so that mopar solution was to switch to a in-tank retrofit. I've had problems with other rotary vane pumps (Holley) when I tried to use them with diesels. They simply stop pumping. I think it's a viscosity issue that allows the vanes to stick. A google search for cummins carter fuel pump will tell you all about the troubles they have. Pretty much everyone moves to a AirDog or FASS pump with them. The pulse pumps are fine for a low performance diesel like the 6.2/6.5 and smaller engines. But I'm a firm believer for the gearotor design pumps (AirDog/FASS) for anything performance related. They also lend to "alternative" fuels much more than a vane style, if you're into that.

 

[Drock]

The stock mechanical fuel pump is more then adequate to support a turbo charged 6.2 or 6.5. Running an electric pump on a switch is nice to use as a back up, to prime after a filter change, or if you just want to fill a bucket with some diesel.

 

[patracy]

The stock mechanical fuel pump is more then adequate to support a turbo charged 6.2 or 6.5. Running an electric pump on a switch is nice to use as a back up, to prime after a filter change, or if you just want to fill a bucket with some diesel.

Kinda hard to get the drainback to work without modifying the block or oil pan. Most every turbo setup deletes the mechanical pump for this provision.

 

[Drock]

Good point, I'm not sure how the GM turbo is plumbed? But the Banks kit I installed on my 6.2 has a block that goes in between the mechanical pump & engine block for the drain back. I suppose you could order one from Banks. Might be cheaper & easier then a fancy electric fuel pump?

 

[Recovry4x4]

If the original posters truck has a turbo, that explains the the electric pumps. If it's a stock N/A then the mech pump is plenty adequate and very reliable.