carb choking engine



66-200 engine, factory 1 bbl carb, c4 trany: tip toeing arond town it has good power, put your foot into it and it bogs down and belches out black smoke. with the air cleaner off, it looks like the butterfly valve is partially closing when u accelerate hard. i detached the choke linkage and wired the butterfly valve open and it runs great..........course the choke doesn't work now.

any suggestions?
Howdy Pierced:

It sounds like you're ready for a carb kit, a good cleaning and a rebuild. These Auotlite 1100 carbs are very susceptable to dirt and crud being sucked into the choke because of the hot air design, which draws heated air through the exhaust manifold. This air goes to the choke mechanism unfiltered! NOT GOOD!

A balky automatic choke is a good indicator of the need to do a carb rebuild. If all else is running good, don't wait. It's easy enough. Just follow the directions in the kit and take your time. Cleanliness is key. You'll love the difference.

Merry Christmas.

Adios, David
Seasons Greetings, Pierced.

Your auto choke shouldn’t flop around like that. Inside the cover for your Auto Choke the coiled spring should have a small diameter loop at the end. The small arm to the mechanical link is supposed to be inserted into this small loop. When the spring heats up the rotation of the spring moves the mechanical portion of the linkage. This connection will also keep the choke from closing under high airflow through the carb air horn.

Checkout the auto choke spring and confirm it still has the loop. If not it would be an easy fix.

Good luck and have a great holiday, Ric.
yes, it seems likw when u gun the engine the vaccum or air flow downward is pulling the butterfly valve partially closed, enrichening the fuel/air mixture and bogging down the engine.

i will have to check the choke likeage, 66, your thoughts makes sense!!!