Fuel Pump, or pumps

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Jan 12, 2008 | 07:26 AM

wayneF250

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From: Mt.Pleasant, Texas

Fuel Pump, or pumps

I have a 94 F250 4x4, are there TWO fuel pumps, sence the truck has Two fuel tanks??? And I've done several mods to engine, Cam, Heads,injectors, etc.... What "size " GPH pump should I get???

Jan 12, 2008 | 08:08 AM

subford

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From: Easton,Ks

What is wrong with the ones you have?

Jan 12, 2008 | 11:04 AM

Conanski

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From: Ottawa, Ontario

What are the stock pumps capable of pushing... 80-90gph maybe? And what does that convert to in HP on a V8 motor? I see some Google searching in my near future. If you have done enough to the motor to require bigger injectors then it's quite possible you need more pump. Problem is, the resovoir the pump is enclosed in won't take a physically larger pump.. and most of the higher volume aftemarket pumps are too big in 1 dimension or another and won't fit. The resovoir contains check valves by the way which prevents fuel transfer between tanks, so you can't just remove it. Maybe an external inline pump on the frame is the solution..

Jan 12, 2008 | 11:55 AM

subford

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From: Easton,Ks

A stock fuel pump puts out 33 GPH and will pump up to a 95-PSI head.
If he needs more that he could wire both fuel pumps to run at the same time.

Jan 13, 2008 | 08:40 AM

wayneF250

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From: Mt.Pleasant, Texas

my fuel pump is going out, the truck dies, just for a sec. when u mash the gas, and gives a code 87 I think, "failed circut @ fuel pump" . Since i've done some mods to engine ....E303 cam, 30 lb injectors, MAF conversion, Edelbrock heads. I was wondering should I go back w/ stock pump. Dont the truck have 2 fuel pumps, since it has 2 tanks. Or do I just replace the stock pump, and add a inline pump to help pressure.....also w/ a pressure gage connected to the fuel rail, what pressure should I have on this engine

Jan 13, 2008 | 09:13 AM

subford

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From: Easton,Ks

With pin number 6 of the test connector grounded and the key on and the engine not running you should get about 42 psi.
Also with it running (idling) and the vacuum hose off the nipple of fuel pressure regulator you should get the 42-psi.
At idle with the hose on the regulator you should get about 32-35 psi.
WOT again about 42 psi.

Yes if you have two tanks you would have two fuel pumps, one in each tank.

The "failed circuit @ fuel pump" a lot of times turns out to be a bad fuel pump.

Last edited by subford; Jan 13, 2008 at 09:15 AM.

Jan 13, 2008 | 09:51 AM

wayneF250

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From: Mt.Pleasant, Texas

So the solution is to replace the pump w/ a stock pump, and add an inline pump to boost up pressure??? also the truck has 208,000 miles w/ factory pump.......bet the sock filter is a little dirty....u think?