'84 F-150 with an '89 carbed 302 using a Mr. Gasket electric 5-10psi fuel pump, filter before pump and before carb. Been having problems with it shutting down on me like it runs out of gas. All the soft line, filters and the pump is new to try to fix the problem. Redid all connections. Power runs through a relay, 10amp fuse, and oil pressure switch, per fuel pump instructions

1. Can't figure out why it's shutting down on me. Like it runs out of gas. Noticed the fuel pressure drops a bit before it cuts off, have a guage before the carb. The wires were also getting really hot near my battery. I can't figure out what is going on. Does it more often when it's hot out. Does ok early morning in the relative cool. But after work, it's been sitting at 90 degrees or better on the asphalt, that's when it wants to act foolish. I straight wired it today through a rocker switch straight to my battery to make sure there's not an electrical problem somewhere.

2. It has a fairly rythmic rpm drop at idle. Truck idles at 750rpm. When it starts dropping, it'll drop to about 500rpm or slightly less then back up to 750. It's got a fairly steady rythm to it. Seems to do it worse when I stand on the brakes (power) at a stop. But it does it reguardless.

Any ideas on where to start?

 

Anybody got any ideas?

 

My rubber fuel lines that connect the sender units in the tanks to the steel fuel line had dry
rotted and crumbled, did you also check those on yours?

The classic heat-related failure pertains to the ignition module mounted on the driver's side
wheel cover, failure of which results in the engine shutting down as if the key were switched,
off, not sputtering & gasping as if it were out of gas.

- What fixes your problem? IOW what do you have to do to get it started again? How long
  do you have to wait? Do you have spark during that waiting period?
- WHAT wires near the battery are getting hot?
- You're checking fuel pressure, have you also checked the flow rate?
- What does a vacuum gauge show?
Define "a bit." And, how much time elapses between your noticing the drop in pressure and
the engine shutting down.

I suspect - but am in no means certain - the rhythmic idle you're experiencing might be
unrelated to your shutdown problems. Do you have any vacuum leaks? How did you adjust
the carb's idle fuel/air mixture?

 

Well, I believe I have possibly narrowed it down to an electrical problem with the fuel pump and wiring. I broke down and wired it straight to the battery with nothing but a rocker switch to cut it on and off. It hasn't missed a beat since. Still got the rythmic idle drop, but doesn't cut off anymore. Been three days now. So, now I'm gonna replace the relay, fuse holder, and oil pressure switch and put all new wiring on it and let it ride. Thanks for the help though. I did check my rubber hose above the tank, it's still in pretty good shape.

 

where is your pump located.it should be as close to the tank as possible.i had mine right after the tank selector valve.

 

It's not more than 18" from the tank. That's as close as I could get it without having to fab up something. That seems close enough to me. It's within spec of what the pump paperwork suggested.