2 tank voodoo

Reply Subscribe

Thread Tools

Search this Thread

Apr 19, 2022 | 07:28 PM

gtex

Thread Starter

Lead Driver

Joined: Apr 2001

Posts: 6,175

Likes: 21

From: Texas

2 tank voodoo

anybody got a nice simple way to explain how the pumps and plumbing work between the two tanks on a 1996 f150 with a 4.9 engine?

i may have one or both pumps going bad. but it feels like there might be something else going on. is it possible for fuel to move from one tank to the other?

Apr 19, 2022 | 07:52 PM

R&RFord

Fleet Mechanic

Joined: Aug 2015

Posts: 1,829

Likes: 362

From: Candy Mountain

The system delivers more fuel than the engine requires, so you have a fuel return plumbed into each fuel delivery module. The fuel delivery modules have check valves to control flow, and make sure fuel is returned to the energized fuel delivery module. When the check valves fail the wrong tank may receive the return fuel.

Apr 19, 2022 | 08:01 PM

gtex

Thread Starter

Lead Driver

Joined: Apr 2001

Posts: 6,175

Likes: 21

From: Texas

is that check valve part of the pump assembly or something that could be replaced easily?

Apr 19, 2022 | 08:06 PM

R&RFord

Fleet Mechanic

Joined: Aug 2015

Posts: 1,829

Likes: 362

From: Candy Mountain

It is part of the fuel delivery module, and is not supposed to be a serviceable component. Ford made a fix with check valves that mounted externally to the module. You might be able to find one...

Apr 19, 2022 | 08:07 PM

SFaulken

Cargo Master

Joined: Nov 2009

Posts: 2,190

Likes: 620

~~Is there some good reason that there's two threads going right now, from the same OP, for the same issue?~~

Nevermind, it looks like the other thread got vacuumed up while I was in this one. My bad.

Apr 19, 2022 | 08:55 PM

gtex

Thread Starter

Lead Driver

Joined: Apr 2001

Posts: 6,175

Likes: 21

From: Texas

Quote:

Originally Posted by R&RFord

It is part of the fuel delivery module, and is not supposed to be a serviceable component. Ford made a fix with check valves that mounted externally to the module. You might be able to find one...

thanks. i guess the right thing to do is pull the bed and replace both pumps and figure out what else i can do while i'm in there.