Small Engines (Lawn Mowers, etc.): Craftsman Lawn Mower, craftsman lawn mower, carberator

Question
I have a Sears 6.75 Tecumsceh lawn mower, and after cutting the grass, if you let it set to long it is hard to start, plus the air filter fills up with gas.  You can hear a hissing sound coming from the carberator, along with gas and it sometimes locks up when starting.

I was just wondering if you had any thoughts on this that could assist me in repairing it.

Thank you for your time.

Answer
It sounds like there is a problem with either a worn inlet needle and seat in the carb, debris under the inlet needle or the float is bad.  You will need to remove the carb, clean and inspect it.  The inlet needle will be worn out if you can see a distinct groove in it.  The float will be full of fuel or won't pivot freely if that's the problem.  If you find debris, make sure you clean out the fuel tank and check your gas can too.  Hope this helps.