What causes this stalling problem?


#1

I just had my 72 Skylark tuned up, when I start it and put it in gear it makes popping noise and stalls, I restart and let it run a for a few minutes and it will finally go. Once it is warmed up in runs great. What causes this stalling problem,? I guess I’m too old to remember.


#2

Sounds like a lean fuel condition most likely caused by a faulty choke on the carburetor. The “pop” should be coming from the carburetor. The choke richens the mixture when cold by restricting air into the carburetor. It runs well when warm because the mixture is correct for a warm engine.

Fix the choke.


#3

A classic response from Click and Clack used to be… “choke pull-off.” It’s a vacuum-operated device that pulls the choke plate slightly open within moments after the engine starts.

You can look at the operation of the choke by removing the air filter cover, and watch while someone starts the cold engine. Be careful about backfires. Keep your distance and wear eye protection.


#4

Mustangman: Sounds all to familiar. I typically solved automatic choke problems with inexpensive manual conversion kits.


#5

My early 70’s Ford truck does this sometimes. One time it was b/c of a faulty inlet valve in the carb. Another time it was a faulty accelerator pump, also part of the carb. Another time, a little screw came loose on the side of the carb, and the choke wasn’t working correctly. In some cases I think the mixture was too rich, in others, too lean. Both can cause this symptom. Currently my truck will do this if I pump on the accelerator pedal too much before starting it up. Especially if I hold the throttle partly open during cranking. If I just pump once, then let off the pedal completely and crank the engine, it starts up perfectly. So you might try experimenting with some of those ideas.

Edit: Just remembered, another time it was caused by a vacuum leak, a vacuum operated device sprang a diaphragm leak, but since your engine runs fine otherwise, that’s not likely in your case.