One of the local tree guys has dropped off his mate's MS231 for me to sort out. Apparently it runs, but it has bad idling and throttle response. I've never looked at one of these saws before, but looking at it now: I'm guessing that it's a strato-saw, but not m-tronic. Says it was made in 2011. Anyone know much about these beasts? Anything to look out for? Also I've never stripped down a strato carb before - anything I should look out? Any advice/guidelines etc.?