Hey, new to the forums but not my Ford.

Well, the lumbering beast of an F-150 I drive. It's been in the family for a while and it's been passed on to me. Unfortunately, it's having a hard time starting from the front fuel tank. It's an XLT with a 351 and the optional rear tank (steel). Thing is huge... extended cab, long bed. Try parking it...

Anyways, it's been struggling with the front fuel tank, rear is business as usual. It's got a fresh new fuel filter, just had it's first taste of Mobil1 and a friend and I ripped a positive cable off a dead Ford since my cable was shot to hell and rusting. All in all, everything has been fairly simple. Just plug and play.

The fuel tank is a bit trickier, mostly because I'm lost. And broke. There are fuel pumps from 50-250 dollars and there's something about gallons per hour? Anywhere from 25 or so to 150+. All I know is I've got the ability to lug around 30 plus gallons of fuel and that 351 won't die but uses a whole lot of gas.

A 5.8 liter engine is freaking huge so I don't want to starve it of gas. For now I'm mostly relying on the rear tank as the front one is going but it's only a matter of time. I'm fine with the pump going, I think we've spent like 500 bucks fixing the truck in the last ten years. It's a 175k miles and still rumbling around. Fuel pumps break, whatever. I'd just like to know how many gallons per hour I need. People keep throwing out these formulas and math and I don't get along and I don't know what the hell they're talking about. Domestic cars are too easy, I'm used to my long-distance driver of a Subaru Outback. This simple Ford has got me stumped though.

Anyone have the same head-scratcher and figure it out?

 

First of all though guys will disagree with me, replace it with another Motorcraft pump. If you cheap out, you'll be replacing it again in no time. Forget GPH. It goes by what tank is in the truck. Look up the size of the front(midship) tank in your manual. It will either be a 17 or 19 gallon tank. Then order what you need, install, done.

 

Something to consider, sounds like the pump is going, but, how does the fuel gauge work on the front tank? When buying a pump, you can buy just a pump, or the pump and sending unit. If your gauge isn't working well on the front tank, id spend the extra $$$ and get one with a sending unit because you'll have done the hard part, dropped the tank. When my front pump went out, my gauge was now working properly, when I pulled the pump, I saw the float was full of hairline cracks, and would fill with gas, and sink. So if you have the opportunity to kill two birds with one stone, go for it.

 

Sounds like the Fuel Delivery Module (FDM) in the back tank is bad (has a bad valve in it).
Sounds like the front one is working OK.

 

What year did they switch from the selector valve to FDMs?

 

For trucks 1990.
For vans 1992 at least the 1991 van still had the HP pump on the frame but had only one fuel tank.