mybreathyourlung

Hi,

I did a search first and didn't come up with anything easily so hopefully this hasn't already been addressed.

I have a '79 302 that I got this past winter. In the cold it always had a hard time starting up but after a three or four tries and some idling, it would get there. Now that it's warmed up a bit it only takes maybe two, but lately I felt it lurch a few times while driving. I sprayed carb cleaner in there but it didn't seem to help at all.

Today I stopped for gas and it wouldn't start back up. I assumed it was maybe flooded so I let the carb sit open for a bit and let some fumes out but no change. Gas squirts into the carburetor and I get a spark. I had someone drop off a new coil assuming that's what it was at first but it made no change.

When I turn the key the engine cranks and when I press on the gas the engine roars but if I let go of the key or the gas it just shuts off immediately.

Just for some history, this is my first truck and I know little about automotive stuff. I got it because automotive work is the last frontier I don't know much about. Thanks a lot.

Kickprivate

If you haven't already, do a tune up on it. oil, filter, plugs, spark plug wires, cap and rotor. Inspect the emissions system and make sure everything is in good running condition, no broken vac lines, misplace vac lines or loose vac lines. If you are feeling frisky pick up a timing light, mark your timing mark off the balancer, read the emissions sticker and follow the standards on the sticker so the correct conditions are met.

On my truck I had three broken vac lines and two that were pulled off, for the first month i had it; it would stall out nearly every time I stopped and didn't keep my foot on the gas. I repaired the vac lines, set the curb idle then the air mixture, I was still having a couple problems so I rebuilt the carb and it does very well. After I made sure the timing was correct and stock, (8BTDC) it began to idle steady and it hasn't stalled out again since.

Pick up a Haynes and Chilton manual and keep them in a handy place. They are a life saver and can become your best friend when related to your truck. It can remove any guessing you have to do and get right to the root of the problem. The haynes manual for your truck is based on a teardown/rebuild which is the one I have and it is a great starting point for any problem.

At the gas station did the truck restart or did you tow it home?

christian62

jus adjust the air screw an the fuel screw, is it 2 or 4 barrel

mybreathyourlung

Thanks for the manual tip, I'll go searchin for one right now. I'm really unfamiliar with vac lines but I'll do some research on that and figure out what may need done. I'm pretty sure I need to take the carb apart and give it a good clean, at the least. A friend came and he towed me home.

I'll look into adjusting the fuel/air screws. Thanks for that suggestion. It's a 2 barrel carb.

christian62

u also got a diaphram pump on the bottom an if its gettin week it'll make it hard to start an have bad throttle response but those trucks r the best trucks to ever b made, if i was u i'd rip all them vac lines out an get u an old school straight 2 barrel an u aint gotta worry bout nun of that crap

mybreathyourlung

Is the diaphragm pump located in the carburetor?

Since the engine is cranking and seems to run at first then cuts off, could the problem be fuel related? Filter or pump? I'll check the carb settings tonight and see if I can eliminate any problems there.

Kickprivate

This guy has a 6 part video on a build of a Ford Motorcraft 2bbl 2150 carb which I think is the one you have on your truck. Its cheap to rebuild at about 35-45 dollars for everything. I can list everything I used to rebuild mine if it would help.

The kit includes everything you need for a complete rebuild, including the pump that he is talking about, needles.

He also talks about setting the choke pull off, the fast idle cam and mixture screws, I would suggest giving it a look over.

Kickprivate

Double Post

mybreathyourlung

Thanks for that video, it'll definitely be my reference once I learn Canadian.

So is the consensus that I rebuild and adjust the carb, check the fuel filter and see what happens then? There's no easy explanation for my problem?

Ben the Isäntä

Try replacing the accelerator pump, my truck was running rough and would cut out, and I replaced the accelerator pump and it helped it alot, also I would take the carb off and do a complete clean on it