Good day guys just a comment on the gms .47 engine problems , i had a similar problem and solved it by fitting a os LC4/3 longreach glow plug as gms recomend using a long reach plug and i have noted some of you are using a os no8 plug wich i myself was using . I am running a gms .47 abc with a (silver centre) pipe and no baffles I also found that people some times over tighten the carb wich ovals the hole and affects tuning .
Hope this might help have a great day