Try removing the muffler clamps and let it vent at the clamp , mine stopped up on me last week and so did my brothers the last of week before last, mine is an 89 his an 86 , his just suddenly quit mine would run, but slowly, wouldn't make
the cart move . if it cranks with the muffler unhooked ,build a fire with wood, charchol or just somthing that will burn long and hot toss the muffler into the fire and let it burn for 2 or 3 hours then use pliers to take it out to cool and put it back on .hope this helps