Reply to "rough running motor"

I vote on the ignition switch. The "run" contact internally is loosing it's ability to make constant contact.


I agree that the inlet valves can be an issue but what they normally do is stick open after the carb was permitted to evaporate it's fuel out of the bowls after the car sits for a while.

The dried ethanol gas acts like a glue until the fresh gas cleans it off, acting as a solvent.

The problem is that the valves are stuck open and the carb will flood big time, like Niagara Falls.

Holleys are particularly susceptible to this, Webers not so much but I don't see that in the description of the symptoms.


Ignition switch symptoms can vary. I had one where the car would turn over and start but when you released it from the start to the run position it would shut off.

Dried electrical grease internally was evident when I opened it. No sign of burnt contacts.

The spring loaded contact pins were no longer moving freely up and down because of the dried grease in the switch.