Hi All,

Odd thing - went to start my f250 superduty and it just cranked... I have a fuel pressure gauge and put it on the passenger rail and had 0 psi. I used a voltmeter at the fuel shutoff on the passenger side and it had 12volts while cranking. welll - i just ordered a fuel pump at this point.

Was that the right choice?

I started siphoning gas out in expectation of the job next week. Theres lots of room under the truck... as you lower the tank do hoses or fill lines get bound up or is it a fairly easy job? Any tips???

 

Before you do anything, did you check your fuel pump safety cutoff switch?

 

Did you check the fuel pump fuse? Its a 20A fuse at location #40 in the fuse box in mine. If the fuse is blown replace it and see if it blows again. If it does then its probably a bad pump. That was the situation with my '94 Explorer. After I removed it, I measured about 0.2 ohms across the pump wires so it had shorted out internally.

Also, can you hear the fuel pump running when you turn the ignition key to "run"? If you can, and the gauge still reads 0psi, then its either a bad pump or a blockage some place.

Good luck and let us know what you find!

 

Thanks - the cutoff switch by the passenger front door under the glovebox is where i was checking voltages. It seemed to be engaged - and then i unplugged it, found wiring diagram, im able to jumper the fuel pump voltage feed and also monitor it with a dvom / test light. As I crank it goes to 12 volts with enough energy to light the test light.

Thats why im pretty sure its not a fuse and must be something downstream.

I do not hear the pump running - i'll try that once more and listen closely for it. I recall in my vette a 5 cent 1 inch piece of hose inside the tank between the pump and the aluminum pipe disintegrated.

Any advice (or horror stories) dropping the tank or something else to check would be appreciated.

 

Sounds like the same thing that happened to my friends V10. He also checked the fuel rail pressure it was at zero. Instead of draining the tank and dropping it, only 6-8 bolts hold the bed on, it is real easy to remove them and the the screws holding the filler neck. Then jack the front of the bed up or get a couple buddies to lift it, its not very heavy. Watch for anything else attached to the bed as you go and block it once you have enough room to work. Dont forget the top seal we did his twice, completly back together putting everthing away and found the new seal in the box, bummer. Did it in less than an hour the second time.

 

Thanks - ill get my parts by next weekeend. I am considering that bed lift approach. Looking underneath there seems to be some "cable" tie downs strapping the bed down in addition to the bolts - didnt see those in the service manual.

So those 6 bolts go into stationaty/welded nuts in the frame? Or do you have to get a socket/wrench underneath? My luck it wil be one of 6 with an issue.

 

The nuts are clipped to the frame, to keep them from spinning. They are crimmped to keep them from vibrating out, so the bolts will be tight all the way out. Measure the bed to cab gap before you start and reset that gap when your done, and realigne the bed. You will need the tools to release the fuel lines from the pump, I believer there are 2 sizes used.

 

Wow - I didnt know so much engineering went into 6 bolts - http://www.taptite.net/pdfs/PR-171.pdf

 

Thanks - the truck is fixed. It was the fuel pump.

Here's my lessons learned:

- I chose to do the "remove the bed" method in a modified way, i took out the 6 bolts in the bed, and a tie down (located on frame by the tire on drivers side)
- i removed the screws by the gas tank filler , but it wasnt necessary since the hose / neck never pulled back , i didnt remove tailights or wiring
- I jacked up the driver side of the bed using a floor jack and a 2x4 and inserted 3 2x4's flat under the bed ath the center rest and forward by the cab and then set it back down (seems like the center was the only support point with a load)
- At this point you could sit under the bed and see the top of the tank and connectors for removal
- I found my rockauto ac delco replacement pump had a different top that wouldnt screw down under the plastic retainign cap the old pump used - it did have the same guts dangling below... so i had to carefully transfer hoses, wiring and components to the old pump top

Ok - here are some other miscelaneous notes:
- by the fuel cutoff switch passenger side floor board - the connector has 3 wires, the two fatter gauge pass power to the pump - the other is an indicator to the dash that the switch is tripped.
- When measuring with a dvom, i have 6 volts there with key in ignition on and 12v when cranking. This is a little contradictory to the ford electrical manual which shows the speed resistor downstream from the switch but as an engineer my real world test tells me its before the switch.
- Seems like this location is a great spot for a kill switch to help protect the ride
- when the pump seats in a "socket" int the tank, the v part of the cylinder is facing you - tabs that latch are left and right (forward/rear of truck)


Oh yeah - dont forget to plug the pump connector back in for it to work dont ask

have pics i need to post soon.

 

Good deal! Glad you got it running again

 

There are 6 bolts holding down the bed, they came out effortlessly for me. Nuts below stayed intact so work is done from the top.



If you lift the drivers side of the bed and support w/3 2x4... thats enough clearance to do the fuel pump. Note the frame strap was unbolted.


Here's a pic of the top of the fuel tank. That black retainer ring unscrews. I used a screw driver and a few taps to encourage it to release and later to tighten it down.



Here's a pic that shows the differences in the top pump plate. A dissapointment but the parts are transferable with some patience. The yellow fuel level wire has a plug disconnect in the middle but its nicely shrink taped - i unsoldered the yellow wire at the fuel level sender and re-soldered after threading the wire through the old pump cap. All the other electrical connectors unplug. That shiny pump has a label that says 1999 F250 ... not.



Here's a pic of the fuel pressure gauge connected.



The fuel cutoff switch is on the passenger floorboard. For me it was a convenient test point to be sure 12 volts was being sent down to the pump. Jumpering the two heavier gauge wires is same as the fuel cutoff switch being engaged.