RE: ENYA Carb Settings...?
What you have is probably one of the best engines ever made back in those days as far as a workhorse goes. Follow what you've been told so far about adjusting the idle setting. But is the engine actually new or just new to you? If it's really new then run it in carefully and take your time. If it's already run in then use a fuel with a healthy dose of castor. I always used 25% all castor in mine which was probably too much but was more or less a standard brew back then.