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I have a 1950 Chevy 3100 with a 261ci and a single barrel carb. Driving home from work the other day I stalled out on the side of the road. I was able to get it started again when I pulled out the choke all the way. It was driving rough but I managed to drive another mile or two before it stalled again. I was able to get it started again and was able to keep it running with the choke out. It was running rough and backfired a couple times. I finally died again a mile from my house. I had my wife bring me some tools and a can of gas, here is what I did from there:
- pulled the fuel line from the filter then cranked it to see if the fuel pump was working (good)
- blew the fuel filter out with my mouth to see if it was clogged (good)
- Pulled off the oil bath and moved the accelerator linkage up to listen for the sound of fuel spraying in the carb (no sound)
Finally I poured fuel directly in the carb and it started and ran almost perfect. I drove it the rest of the way home and parked in my garage. My dad suggested I need to rebuild my carb. Does anyone have any further trouble shooting steps I can apply in order to for sure determine this is the carb, before I rebuild the carb.

Out of fuel?

Stuck float. Debris blocking needle/seat. If it’s running good now I wouldn’t do anything but drive it. If it does it again then maybe it’s time for a carb cleaning.🛠

Did it run good with the fuel that was poured down the carb? Or did it run good on its own power and fuel, after the fuel was poured down the carb?

Sounds just like junk in the tank clogging up the line. If the fuel line runs out the bottom of the tank, carefully remove the shut off fitting and see what drops out. I would not do anything to the carb until you are sure the fuel flows freely from a clean tank.

Thanks for all the response. I think I am going to check the tank to make sure there is no debris and the lines are clean, before I move to the carb.

Save the carburetor for last.
Check the fuel delivery from the pump by removing the fuel line from the carb, crank the engine over with the starter with the ignition off.
Catch the fuel in a plastic Diet Coke bottle (Diet Pepsi if you break down in South Carolina or thereabouts).

What everyone said, I'm not sure about 1950 but my 54-3100 has a drain plug on the bottom of tank. Don't touch the carb yet. I need to check with John to see if maybe I can send a loaner out with a new gasket to some of the folks that have model "B" carbs. Not selling just loaning. Ed

I have had a similar problem before on other vehicles. If the other suggestions don't help, maybe try replacing the fuel pump. Several times I have been plagued by intermittent fuel pumps, especially in cold weather. The key is that it is an intermittent problem, the worst kind to diagnose.
don

My 1950 3600 would do the same thing. I fixed it by putting a fuel filter upstream from the pump. It seems crud from the tank was getting into the pump allowing it to pump fuel in both directions. The amount going to the engine was not enough to keep it running longer than 25 minutes or so. I betcha I had the carb off and torn apart at least a half a dozen times trying to fix the problem with no luck. I do have a glass bowl filter at the carb and noticed that when the engine would quit, there was very little gas visible in the bowl. When everything was working, the bowl would be about 3/4 full.

My 1950 3100 did same thing...very small crap passing into carburetor from tank.
I put an in line filter on it . I cut the rubber hose at bottom of tank to hard line.
(Note I already had the AC glass filter at fuel pump) Does not filter FINE particles.
Problem SOLVED instantly. Also amazing the tiny debris in the in line filter you can see from your tank.
See pictures. The picture with Debris is only driving it a few days!

I had a similar experience with my 38's 216. I also had some backfiring. It would start to die and then rally, buck and surge and backfire. It turned out to be the condenser. I hooked up my timing light and pointed it into the windshield in the garage. Every time it started to fail I could see the spark failng too.

I have been converting my fleet of ADs with the later sending units which have the fuel pickup as a part of it. They bolt right in and the fuel is picked up just above the bottom of the tank and has sock on the end of the pickup tube. This prevents blockage from debris sloshing around the bottom of the tank from clogging the fuel outlet.
The on again/off again blockage from debris with the original setup makes troubleshooting a nightmare.
Carl

What Carl and Shaffer said. I put a newer sending and pick up unit in as well. It takes a little plumbing with some steel brake line but is a major step up from the old arrangement. I eventually had the tank cleaned, the new unit and a filter prior to the fuel pump and one at the carb. Probably overkill but it keeps the junk out of the carb.

Use the nickle copper line for the top feed sending unit. It can be bent by hand with minimal kinking, except for the tightest of bends. Use a tubing bender for the tightest turns.

Well it turn out the problem was the ignition coil went bad, I changed it and it started right up.

Glad that you got it going. Hope that coil really was the issue but I'm curious why a failing coil (poor or no spark) would be helped by running with choke, albeit badly. Bet that coil cooled enough or bounced enough to give enough fire to a richer mixture. ...or one thing had nothing to do with the other. What is the old saying....if you think it's fuel related....it's usually electrical and vice versa. Good to hear yours worked out pretty straightforward.

How did you figure out crud was getting into the pump and pumping fuel both directions?

Gazz, how could you tell the fuel pumping was pumping in both directions?