Hi

You say the engines new, but like here in the Uk, were still getting some of the problems with engines that have not been updated. just older stock, that had issues.

Yours sounds like the carb problem they had awhile ago. what serial no. is it? Speak to DA or their agent in SA. if any works needed they will do it foc.

There should be no problem installing any 2-stroke gas engine inverted.

Hope this helps