+1 on adj. carb, next rebuild carb. If that doesn't do it press/vac test for leaking crank seals. 246 doesn't have an impulse hose has a port in the block between cyl and carb. Gasket could be bad. Carb bolts could be loose causing vac leak. Posting an IPL it maybe of some help to you. My file is too large won't let me post it. Good luck 246 is an awesome little saw have two of em. Father of the 346XP.