I have two Seagulls, both with Villiers Carbys and assuming you have the same setup, the first thing I would check for, is to look through the choke opening to the throat of the carb behind, and see if the piston, (which is attached to the throttle cable), is going right to the bottom of the throat when you move the throttle lever backwards and forwards. You you should see the piston rising and falling and if it’s not falling flush with the bottom of the throat the motor will still keep running.
The other thing to check, is that the knurled thumb screw on top of the carb has been screwed down correctly. You will see a little cut away in the top of the knurled thumb screw that allows the throttle cable to sit correctly…………it’s very easy to screw that down and trap the little cable fitting.
Hope this helps.
Monte NZ
I sold this motor but would like to help the buyer solve this problem. The brass piston inside the carburetor throat was not closing all the way. Earlier on, the motor was shutting down as it should. I do recall adjusting the location of the throttle on the tiller handle sometime prior to the issue.
After looking through some literature, that was kindly sent to me by cajuncook1, there is a very specific design location and orientation of the throttle, and mine was set too far towards the tiller grip. I’d like to readjust the throttle and see what happens. The cable adjustments didn’t help, and the keyed carburetor cover is positioned correctly. Service sheet no. 7 in a service manual shows the center of the throttle to be only 2 1/8″ from the tiller tilt bolt. I tried to post the manual, but the file is “too big”.
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