Small Engines (Lawn Mowers, etc.): 6.75 HP Craftsman Stopped Running, fuel flow, gas cap


Question
Michael,

I have owned a Craftsman self-propelled mower for 6 years and today was the first time it stopped running while mowing the yard.  I removed the air filter and cleaned it a bit thinking it might be the problem but it still would not crank.  What are your thoughts?  Thanks in advance.

Jeff

Answer
Hi Jeff,

You will need to determine if the problem is a lack of spark or a lack of fuel flow.  Right after it quits, remove the spark plug, reconnect the wire and lay it against the engine head.  Pull the engine over and watch for spark at the plug's electrode.

If good, then try to start it while squirting fuel or starting fluid into the carb intake.  If it starts and you can keep it running by adding fuel, then the carb most likely has dirt, debris or gummed fuel inside.
You will need to remove the carb, disassemble it, clean all the small internal openings and blow it out with compressed air.   Probe each and every hole with a small wire.   A carb rebuild kit wouldn't hurt either.  

Another possibility if the problem is fuel related: Check the gas cap to make sure it is venting and not causing a vacuum in the tank.  

Let me know how you make out.
Michael