Thanks NormK.
I ended up replacing both the cap and the cover 'boot' and all now seems to be working well. I don't seem to have much throttle control but watched a youtube vid that showed the need to replace the 'O' rings on the manifold, carbie and the starter to combat any air leaks so will try this when I get the parts next time I'm in town. I was going to buy from Outdoorking online but haven't been able to register for an account.
