How to install facet as prime pump

[ComatoseLlama]

Hello,

I've been chasing my air intrusion issue lately and have grown tired of cranking for 5 mins and fogging out my entire street every time I start the truck.

I am considering installing either a 40222 or the cube style 40109 as a way to prime my fuel system before starting the truck. Should I be trying to install this before or after the mechanical fuel pump? The soft line between the frame and the mech pump seem like an ideal location but I'm not sure if I should be replacing the hard line instead.

This will be on a push button to prime up the system as a band aid until I can get the fuel system all sealed up, I've got a transmission job on my Subaru to do right now so the truck is on the back burner and a band aid on the fuel system will have to do for now

CL

 

[IDIBRONCO]

That best way would be to run that and the mechanical lift pump in parallel so that you don't rupture the diaphragm in the mechanical pump. Ask Selahdoor how he did his.

 

[TNBrett]

Basically you want the e pump and the mechanical pump parallel. So starting at the rubber line going to the original lift pump, add a tee. One side feeds the lift pump, one side feeds the prime pump. After each pump add a check valve, then another tee to join them. This then feeds the filter housing and then the IP. The cheap made in China check valves will probably be the weak link.

 

[ComatoseLlama]

Finally managed to find his setup hidden in a old thread, seems like a good mod regardless of air intrusion issues


Post in thread '1992 7.3 IDI Wont Start.'
https://www.oilburners.net/threads/1992-7-3-idi-wont-start.87858/post-1056524

 

[Booyah45828]

I've always thought running a mechanical and electric pump parallel would be good for fuel filter changes at a minimum. I'm not a fan of using it to bandaid intrusion issues, but I understand that you gotta do what you gotta do sometimes.

Know that the way some pumps are designed, check valves in the system aren't required. For instance, the mechanical pump on the block has 2 integral check valves in it already, otherwise it wouldn't function as a pump. I believe most of your "cube" style pumps are this way as well, with a built in check valve, so installing more valves would be redundant and IMO unnecessary.

Filling the crankcase with fuel due to a ruptured diaphragm hasn't been mentioned yet, but I'm sure someone will come along and say it, and AFAIK the only people who have had that problem were running the pumps in series with the electric pump feeding the mechanical.