fuel pump replacement?
 

Well, I am a nary a few weeks in to ownership and have a couple big problems. The first being a truck that will not start.

When I spray a bit of quick start in the carb she fires right up, but then quickly dies off. Took off the fuel filter (which looks to be relatively new) and floored it, tried to crank it..... and nothing. No gas out of the hose.

I did also notice that the last time I drove it under any acceleration past 1/4 throttle i got no elevated response. She even stalled out a bit under heavy throttle.

Three questions.

1. Do you guys think it is most likely the fuel pump?
2. Is there anything else I need to test before trying to replace it?
3. How hard is a fuel pump for a novice to try and replace? (aka, should I get a mobile mechanic)

Here we go:-X15

That sounds like the issue. I have a 75 f100 w/360 and had to replace mine. Try pulling the line to the carb off the pump, turn the key over and see if any fuel comes out. If not, your pump is bad or it's not coming from the tank.

It's probably the pump but before you replace it, crawl under the truck and check all the "soft" lines in the line between the tank and fuel pump. These can get hard from age and crack allowing the pump to suck air and lose it's prime. Probably wouldn't be a bad idea to replace them regardless.
If you have a longbed there should be three, one from the tank to the hardline, then about midway there should be another, then the third one where the line goes to the fuel pump.

Agree. Also the fuel lines can get so soft with time and alcohol they collapse and get sucked shut by the fuel pump. Either way she does not run so well if at all. Suggest you replace soft lines first then continue trouble shooting if necessary.

had an hour or so before dark and got battery disconnected, checked all the "soft" lines and everything seemed to be in good shape.

disconnected the inlet and indeed had quite a bit of fuel flowing so i plugged it up.

my question now is how in the world do i get at those bolts on the fuel pump!? anyone know the size off the top of your head? it is really tight in there...

any tips or tricks would be much appreciated as i am hoping to get it up and running by the weekend.

When you say you "disconnected the inlet" and had fuel flowing, do you mean you disconnected the line going to the carb and cranked the engine? That's how you'd know if the pump is pumping, if it spurts fuel when you do that. But you say you disconnected the battery, but that means you couldn't have cranked the engine.

Here is what I have done so far in this order.

1. sprayed quick start in carb and got engine to turn.
2. inspected lines going in to carb and fuel filter
3. disconnected fuel line to carb and cranked engine (no fuel come out when cranked)
4. disconnected battery
5. disconnected lines to fuel pump

i am now having issues getting to the bolts to remove the filter and looking for advice. truck is stationary in the driveway so i can't get it up on ramps.

OK, good. I suggest you now try this: you say you've disconnected the lines going to the fuel pump. Run a hose from the fuel pump inlet (the one the line from the tank goes into), and into a small gas can with some fuel in it. Hook the battery up and crank the engine again. So basically you've now eliminated the fuel lines and tank from the equation. If you are still not getting fuel pumping, then you can be pretty sure the pump is gone. If you get fuel pumping, then your problem is the line between the pump and the tank (or inside the tank -- fuel pickup blocked, etc.). You don't want to change that pump until you are certain it's gone.

As for the bolts (assumign you do need to replace it), I'm guessing it's an 8 cylinder since you can't get at them. I work mostly on 6's but I know that on 8's it's a hell of a lot easier from below. I'm assuming what you have in the way is the power-steering pump. Yes?

and a radiator hose, and an oil filter...

yes 390 v8.

How accessible is the pump from beneath, without lifting the truck? And how about just jacking and blocking it on that side? But if you do, block her good man, it ain't worth killin or cripplin yourself for.

Maybe a dumb question, but have you thought of taking off the wheel and well liner and getting at the pump that way?

Look at the fuel pump, does it have a round steel cannisiter that threads off/on?

If so, inside the cannister is: C4AZ-9365-B .. Corrogated Paper Cartridge Fuel Filter (Motorcraft FG-1A) / 1964/76 myriad FoMoCo vehicles.

This is the original location for the fuel filter on F100/350's and since some/most (pick one) people are unaware, they install an inline filter.

Meanwhile, this filter probably hasn't been changed since Reagan was prez, and so is getting more clogged up every day.

I have done 2 pumps and I had the best luck from below and thru the left wheel well. the bolt size is a 9/16 and a socket can be use don the front one but I had to use a wrench on the back one. when putting the new one on, have patients and get both started because the arm that goes in the motor will give resistance. Good luck, it's not that bad.

Also helps if you use a little dab of gasket sealer to stick the gasket in place on the block first.