So I recently had my 3rd raptor 100gph lift pump fail on me. This time around I've decided to relocate the lift pump just outside of the gas tank on the frame of the truck and run more 1/2" fuel line. This raptor pump is for a 98.5 cummins. It's made to have 3/8" coming in and 1/2" coming out. Weird i know(dont think the 99 and up raptor pumps are this way). So out of my gas tank I've got about 1' of 3/8" with a small inline fuel filter before it goes into the lift pump. Then I've got 1/2" line coming out of the lift pump and up to my bigger fuel filter. Its about 5ft of 1/2" line total.
Now the questions...The lift pump is set to about 19-20psi at idle, but now when I get on it my fuel pressure drops all the way down to the 12-13psi range. Now I know I'm getting more volume with the 1/2" line, so I'm wondering if i should be concerned about anything with a pressure drop like this with my setup? Is there a chance it could cause a hickup in the fuel system? Is the lift pump going to be working harder? These are things I'm wondering. Let me know what you think. Thanks.

 

Also the truck has an edge jwa now. Need to update my sig.

 

Any answers? Thoughts? .02 cents?

 

So I've called and talked to a couple different guys at pure flow airdog. The first guy, won't say his name, told me I needed to take the bottom plate off of my pump and check the O-ring and something else but I couldn't understand him because it sounded like he had me on speaker. Now I know it's not hard to take the bottom plate off, but I replied why would I take apart a brand new pump? I shouldn't have to do that, nor do I want to. I also told him I couldn't hear the last part of his sentence. He hung up on me. So today I called and asked for someone in charge and got Jaron. Jaron seemed more willing to help me and didn't have me on speaker so I could actually hear what he was saying. He told me that the ddrp, raptor 100gph pump thats for the 98.5 24v is designed to pull fuel and not push it and that's why I'm seeing a pressure drop. So it's actually supposed to be up on the engine block. Think it really matters that much if it's pushing or pulling?

 

No comments, but people are viewing so I'll finish my storySo I decided to take dudes advice from pure flow and mount my raptor pump back up on the engine block so it could "pull fuel how it was designed". Well guess what, my fuel pressure still drops 6-8 pounds under wot. Not bashing the guy for his advice at all, I really appreciate it. But it doesn't seem to matter where I mount this pump, close to the gas tank or on the engine block, 1/2" line or 3/8" line. It drops pressure from 20-21 to 12-14 wot. So I'm going to guess this is normal for this pump and run it on the frame with 1/2" line. Let you guys know when it burns up...