Engine hesitation/sputtering.... SOS!

[72f100]

Hey Guys,
Had a random issue pop up over the past couple days and I could use some help. On thursday I was cruising along in second gear, about 35mph. I stepped on it to pass somebody and when I did so, the engine sputtered and hesitated. Took my foot off the gas and it went away for the rest of the day. Over the weekend though, it's gotten pretty bad. When I first start the truck, it drives just fine. But as my drive goes along and I try to accelerate it sputters/hesitates and gradually gets worse and worse until it dies completely. Once I get it started again, it's okay for a little while but eventually goes through the whole scenario again.

It's a 72 F100 w/ 302, 3spd MT, 2100 carb. I"ve checked all my adjustments and checked for vacuum leaks and it all seems fine. Fuel filter and air filter are good, fuel pump only has about 10,000 miles on it. My guess is that it is an internal carb issue. Any thoughts? She's my daily drive and I gotta get her fixed tomorrow if possible!

[ToughOldFord]

It sounds like some junk might be in the carb. May want to check for vapor lock too.

[montana_hiboy]

It sounds as though it may be heat related, possibly electrical in nature, how old is your coil? have you checked the coil?

[72f100]

Vapor lock? I've heard of that, but how do I check for it and fix it if that's the issue?
Yeah, my coil and distributor only have about 2,000 miles on them and are both in great shape.

[NM5K]

Hummm. Usually, a bog, or lack of power when stomping the gas is a bad
accelerator pump in the carb. But... Yours seems to be running out of fuel
even at lower speeds..
I doubt it is vapor lock. That's a heat issue, usually when starting after
sitting hot, than when the truck is running. It's much harder to get the
fuel to boil in a running system with all the air flowing.
To me, sounds like the carb is starving for fuel.
You may have semi clogged fuel lines from the tank. Usually rust
particles if that was the case. You say the filters and pump are good,
but I'd still double check them, and make sure they are getting fuel
from the tank. Also, I suppose it's possible to have a pump with 10k
being bad. But with the old trucks, I'd be looking at clogged lines from
the tank unless you know for sure your tank is rust free.
I'd probably pull the fuel line to the carb and do a fuel pump test.
IE: they should pump a certain amount of gas with a certain time frame.
I forgot the specs, but maybe one of the books I have has it..
I don't have them with me at the moment.
Rust in the tank and lines has been a problem with mine over the years.
The rust rocks and particles get stuck in the lines at bends, etc, and
get stuck. Then more and more get stuck in the same place and
eventually clog the line.
Also, some of the older pumps have filters too. If you stuck a new
pump on an old truck with a rusty tank, it could get clogged after a
while.

[george worley]

My truck did that and it was rust in the tank had clogged up the pickup. Try disconnecting the line at the place where it makes the bend to go to the pump. Mine had a short piece of rubber fuel line there. Gas should run out in a good stream. If that's all right check at the pump. Make sure your tank is venting. losen cap I have had a fuel pump go bad in less than a year. If you put a clear inline filter near the carb. you can check for fuel.

[fordman]

2nd opinoin on the accleroator pump going bad.

[72f100]

So the end result.... (hopefully)

It looks like I just had some stuff in the carb. Cleaned it all out, threw a new, clear fuel filter on there for good measure (old one was a tad bit clogged... oops) and if that's all it was then I am set! Thanks guys!