I have the Weber conversion also. How to check for choke operation on a COLD engine is to remove air cleaner. Look inside carb. throat and observe the choke plate in the carb throat. It should be almost vertical(open/no choke setting). Operate the throttle once and the choke plate should almost close.Engine must be cold.
Once the choke plate closes it will not reopen till the choke heater warms the bimetallic spring enough to open the choke back to "no choke/open" setting.
To check choke heater just crank up engine and after several minutes the choke coil will be warm to the touch.If you blip the throttle after warming up you will see choke plate return to the open/no choke setting.
Also check where you are obtaining the power for your choke. You want power to be supplied to the coil anytime the engine is running. I used the +12v side of the ignition coil for my choke heater.
Also the dieseling can be caused if the carb is not adjusted correctly. See the Weber website for setup instructions. If the idle stop is set to high you will have dieseling problems. If my idle is over 900-950 mine will diesel.

There is a lot of Weber experience on the site. Use the "search" function.


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