Newbie...

Hey guys, was on-line looking for a replacement Walbro carb, and found this site. Looks like a cool place to learn new things and share some knowledge. I'm from Long Island, NY. I inherited my dads old 1994 MTD (Agway) 42" riding mower and am having a bit of an issue with the carb. It's a Walbro LMK that keeps dumping gas into the crankcase. I tried cleaning the carb, replaced the needle valve 2x, and even replaced the float. I'm kinda leery of messing with the seat 'cause I can't find a replacement carb, just in case I mess it up. Anyone have any ideas??? Thanks,Rich.