Hi there I have a husqvarna 372xp chainsaw that wont start.I lent the chainsaw to a friend(idiot) who put diesel in the tank and ran it until it cut out and it wont start now.I have took of the carb and cleaned it also took off the cylinder to inspect it it has slight scratches.I have removed sparkpllug and there is spark also I put my finger over sparkplug inlet and there is compression there.I have tried easy start but no good.All it does is now and then it backfires could someone please help the only thing I did not clean was the jet in the carb.