42cc 18 inch craftsman chainsaw model 358-351910-18. Saw runs great at idle or while not cutting wood, when starting to cut wood just after the entire bar gets into the wood engine bogs down and chain comes to a complete stop.Please Help

Generally this is a fuel / air ratio problem. Usually it can be solved by a carb adjustment. On the carb there are usually two screws, one marked low or L , the other marked high or H. Low is your adjustment for idle mixture, high is for mixture at full throttle. The saw should Always be adjusted to run well during the cut. Make adjustments a little at a time, then try The saw. Continue small adjustments untill the saw is performing well at full throttle while Cutting.

Is your chain brake engaging (accidental bumping)? Remove the chain and bar first then screw in high speed jet until it seats, counting turns as you go. If its less than 2.0 then its probably too lean which would bog down at full load. Back it out 2.5 turns and start saw (minus bar and chain). While full throttle, screw in (leaner) and listen for revs. You will find position which has peak revs, then screw out approx quarter to half turn (richer=more fuel). Revs should be near peak but definitely slower but not rich enough for rough running. That is your ideal setting. You must go richer than absolute peak because of the load when cutting. The low speed jet is for smooth acceleration. Open it up just enough so there is no hesitation at all on acceleration. Also, it should come right back down to idle quickly. If it holds speed after you release throttle, then its too rich. The idle screw is last to set. Low enough to disengage clutch quickly but high enough to idle happily without shutting down.