So I recently inherited this truck from my grandpa and it hasn't ran much in the last two years, it starts up pretty good and runs fine and right about the time it reaches correct operating temperature it dies. I have completely went to the carburetor replaced the brain box twice, replaced the coil, it has a new spark plugs, and a new fuel pump. The last time the truck was running correctly was at 1100 feet altitude and I brought it up to 5200 feet in altitude I did reject it thinking it was flooding it at idle causing it to die but I think I have the carburetor tuned pretty well right now because it runs just fine until it gets warmed up. Any advice and help is much appreciated.


1977 Ford f-250 Custom
2wd with a 400 &NP435 four speed
completely stock
Motocraft 2150 carb

 

Welcome to FTE!


There are a lot of good people here, and most of them love to answer questions.
My guess would be that it's getting too much fuel and not enough air. Perhaps idle mixture or jets (if 2150's have jets?)
But don't worry - somebody will be along shortly to give better advice!

 

Make sure your fuel lines are not next to your headers causing the fuel to vaporize. If you have a clear fuel filter near the carb you can watch the fuel flow. I had a similar issue... Another place to look is to ensure the choke is fully opening after warm up

 

Replace the pickup coil in the distributor.

 

Ok ya the distributor was going to be my next part to replace. The 2150 does have jets and I jetted it from a 57 down to a 54, I recently got a vacuum gauge I need to mess with the idol screws some more but it seemed like when I screwed them in more it wouldn't even start. So as of right now when it was running before it warmed up the screws are out about 2 1/2 turns does that sound about right ?

 

Two tests to try when it starts to stall out
1. Look down the throat if the carburetor and press the gas, can you see a spray or jet of fuel?
2. Pull a plug wire and check for spark.
Post your results back here
if you don't see fuel on #1, its vapor lock.
If you don't see spark on #2, it's the pickup coil in the distributor.
If both tests come back good, back to the drawing board

 

OK #2 I have tested but it was when it was cold does it matter if it's warmed up or not? It had plenty of spark. #1 I will test it tomorrow I know when it's running and warming up everything is working good at shooting good fuel out of the Excelerator pump ports but I haven't checked it while I was trying to die it dies so fast, it'll be hard to catch it but I will hover over it tomorrow and reply back thank you for the advice.

 

If you have electric choke, Make sure the choke is opening when warm. The wire going to it should be 12 volts dc on an aftermarket carburetor and on ford carbs it should be around 7 volts AC to ground
Idle fuel mixture is adjusted by idle mixture screws not jets.

 

It does matter because your pickup coil could be overheating and cutting out. I'd put money on that being it since the accelerator pump is working when it's warm

 

Yup, been there, done that.
Quick check... on a 77 which should have a duraspark, disconnect the wiring connector.
Three wires, one of which is a ground (the black one). test resistance between the other two wires. Should be 600-900. Do this right after it dies.

good luck

 

Ok y'all I finally got it it was the pickup coil, ended up having to just replace my whole distributor. She's purring like a kitten now thanks for all of the helpful information!!

 

That's an expensive way to replace the pickup coil, but the important thing is that it's works. Congratulation and Merry Christmas!

 

It's about the only thing that goes out in a Duraspark. I've always got a few used but good ones on the shelf.