Re: Chugging engine...

Posted by Tim Cole On 2010/11/16 19:04:50

Dear Paul:

This is a common problem. Make sure the heat riser is working for starters.

More likely it is the choke pulloff. This is a vacuum piston that wears out and doesn't pull the choke off enough causing overchoking. Once the motor warms up the choke opens and the motor runs okay.

This can also be caused by a combination of low compression and worn out carburetor.

On the Strombergs there are air atomizer passages that fill up with gum and cause flooding due to syphon action. This requires service by someone with experience and the special jet wrench/puller (ie Daytona, Carburetor Doctor, Classic Carburetors, etc)

To check remove air cleaner, start motor, and open the manually open the choke slighty. If the motor smooths out you have found the problem. There is a specification for the amount of pull off which I don't have handy.

Quite frankly, I would put a manual choke on any carburetor that has this problem because rebuilding just won't help very much.

Good luck.