WD/CO not running cleanly

[gary0003]

My 1944 R/Enfield WD/co has recently developed a rather strange issue. When the engine comes under load (Hills) about 3/4 throttle 35-40mph, it coughs and stutters for a few seconds. It does have a "Talflow" Airbox fitted but used to be fine with it. I noticed the plug was very sooty and dropped the needle 1 notch, which has made it much better but not completely cured it.The plug looks better (but maybe still a bit sooty). I have cleaned out the float bowl which did have some debris at the bottom. any ideas would be helpful please - I have now put fresh petrol in.

Thanks

Gary

[Ron]

Cleaning out the float bowel might not be enough. There are tiny drillings that can get bunged up and need prodding out. The jet block needs to come out and clear out the drilling in the carb throat with fine wire and also the corresponding drillings in the jet block. Remove and blow out the main and needle jets and all other orifices. 

The accompanying picture show the drilling in the throat.  Ron 

[gary0003]

thanks Ron , I think your right, the float bowl has more crap in it again - Its coming from inside the tank so probably have to get some sort of tank sealant?