Fuel Pumps

[Profarm72]

Well apparently my stock fuel pump(s) went out Friday night at the Shootout. I've been looking at the Walbro 255 dual pump setup but have a few questions.

1st question about the dual 255 pumps - is one pump for the internal pump and the other to replace the inline pump on the frame rail or is both of these supoose to be mounted in the tank together?

2nd question - am I going to have to replace the fuel pressure regulator if I decide to run the dual 255 pumps.

I am open to sugestions, let me know what y'all think.

I'm guessing that I'm pushing somewhere in the neighborhood of 450+ horsepower and from what I have read thats about where you start having these type of issues with the stock setup.

Thanks in advance for the help.

[SILVER2000SVT]

The stock setup is 2 155 pumps in parallel in the tank. So the twin 255 is just two larger replacement pumps.

I know a lot of people had issues with burning up the resistor after doing the twin 255's because you are now pushing more current through the resistor on the low flow setting (non boost). I know some of the guys upgrade the regulator and return line to allow more return flow to the tank and then simply bypass the resistor to put the pumps at full power all the time. The down side to this is that it puts more heat into your fuel and you better never go below 1/4 of tank or risk burning out your new pumps. It will also wear out your pumps faster because you will be running them at full voltage 100% of the time compared to 5-10% of the time like you would be if you had a functioning resistor.

[Profarm72]

Do you think there's any way to change the resistor to accommodate for the larger pumps?

also, Is there not an inline pump located on the frame rail then?

I would prefer for everything to function just like stock but to increase the amount of the fuel supply.

What are the guys doing that are installing the Kenne Bell and Whipples?

Thanks again.

[tiffo60]

Do you think there's any way to change the resistor to accommodate for the larger pumps?

also, Is there not an in-line pump located on the frame rail then?

I would prefer for everything to function just like stock but to increase the amount of the fuel supply.

What are the guys doing that are installing the Kenne Bell and Whipples?

Thanks again.

There is no in-line pump, just the two in the tank. When I had mine terry just replaced the two in tank pumps with the 255's. I never had any problems out of them on my KB L and as far as I know they are still holding up...

[L8 APEX]

Buy a new piece of special submersible 5/16 fuel line and the stainless Y fitting. The stock hose tends to rot and split in the tank.

[Profarm72]

There is no in-line pump, just the two in the tank. When I had mine terry just replaced the two in tank pumps with the 255's. I never had any problems out of them on my KB L and as far as I know they are still holding up...

Did you have to upgrade the regulator or were you still running the stock one?

Has anybody ran the GT500 dual pumps?

[Profarm72]

Buy a new piece of special submersible 5/16 fuel line and the stainless Y fitting. The stock hose tends to rot and split in the tank.


Thanks for the tip, I will do that for sure.

[tiffo60]

Did you have to upgrade the regulator or were you still running the stock one?

Has anybody ran the GT500 dual pumps?

stock one

[tucamote]

yup tiffs old 255 still running strong i got a fore fuel hat that i am about to put in too 3 pump setup to run e 85

[TXLIGHTNING]

I have has dual 255's for several years now with no problems. I just replaced the Y fitting with a stainless steel one, and replaced the hoses like Terry said :tu:

[Profarm72]

Thanks for all the info.
Looks like I will be installing the dual 255's then and also replacing the Y and fuel line.
who has the best prices to purchase these items?

[L8 APEX]

I'd buy it all from LFP.
http://www.lightningforceperformance.com/vehicle/Ford/F-150_Lightning_99-04/Fuel_System/Fuel_Pumps/grid/1

[TXLIGHTNING]

I'd buy it all from LFP.
http://www.lightningforceperformance.com/vehicle/Ford/F-150_Lightning_99-04/Fuel_System/Fuel_Pumps/grid/1 That's where I got mine. I know that JJ @ WMS has great deals on them as well.

[99WhiteBeast]

I have has dual 255's for several years now with no problems. I just replaced the Y fitting with a stainless steel one, and replaced the hoses like Terry said :tu:

+1 with stock regulator, rails and resistor for 3 years now. I do have the bigger injectors (60#) to feed the KB.

[Profarm72]

Alright guys, I really apperciate all the feed back.
I have made my purchase from Lightning Performance and ordered the dual 255's, the stainless Y and the fuel line. I also went ahead and ordered the pump relay that they are advertising, not sure I need it but what the heck you never know.
I also ordered the drive shaft safety loop.
Does this bolt in form the bottom or am I going to have to pull the interior to mount it?

[L8 APEX]

Theirs bolts into the cab under the storage tubby I believe. I prefer the two piece by JLP or PSP that runs across the frame. We use to make them out of bar stock from Home Depot.

[Profarm72]

Ok, I replaced the pumps this weekend but still have problems.

I am not getting power to the fuel pumps at all.
I am getting power every where else and to the inertia switch but just not to the pumps. I'm assuming that the inertia switch is the last stop before the pumps
anybody have any idea?

BTW, I know the pumps work because we put power to them and they came on.

Does anybody have a complete wiring diagram of the fuel system and how the power is ran from the main fuse block under the hood?

Thanks!!

[T Hogg]

Ok, I replaced the pumps this weekend but still have problems.

I am not getting power to the fuel pumps at all.
I am getting power every where else and to the inertia switch but just not to the pumps. I'm assuming that the inertia switch is the last stop before the pumps
anybody have any idea?

BTW, I know the pumps work because we put power to them and they came on.

Does anybody have a complete wiring diagram of the fuel system and how the power is ran from the main fuse block under the hood?

Thanks!!


Are you sure the old pump was bad? Maybe it has a wiring problem.

[Profarm72]

Are you sure the old pump was bad? Maybe it has a wiring problem.


Well I found out last night that the inertia switch was not grounded correctly. after I grounded the switch out the pumps came on and the truck started right up. Kind of strange though that all of a sudden I lost the ground. you would think that would be an intermittent problem and not something to just all of the sudden happen.

I need to find out where the ground is located and see exactly what happened to it, I will look for this tonight.

now my A/F guage is reading 20.0 at idle and drops a bit when you give it some gas but then climbs back up to 20.0 again.
any thoughts?

[BradOcean]

I would get the fuel pump wiring problem found and fixed before chasing another problem having to do with fuel. You most likely will knock out both problems at once.