Whipper Snipper starts but stops when throttle applied?

I have a MC whipper snipper. Starts ok but when the throttle is applied it stops. I am able to put full throttle on sometimes and the revs build up but after a short period of time the engine stops. Have just replaced all the gaskets in the carby and cleaned out same. New fuel lines replaced and new spark plug. Running out of ideas and patience. Not wishing to spend any more money, other wise only other option is to purchase a new one but they are not any as good as the older models. H.E.L.P needed before it is put to rest