Yardman2003 rider mower keeps fauling the plugs and shuts down why

check for fuel fault ( blocked fuel filter , no fuel) check for failed spark plug
check for shorted coil wire

If it dies try removing the gas cap. If the gas cap vent is plugged it will do what you described. The other area to check is the coil or what Briggs sometimes calls an armature. You can buy a cheap spark tester at an auto parts store. When it dies put the spark tester on and if there is no spark then that is probably from the coil failing when it gets hot.

Might be a broken keyway keeping the flywheel in time with the crank shaft. have to pull the flywheel off the top of the engine to check it. The keyway is like a timing belt or chain on a car engine. Do not put any lube on the flywheel or crankshaft when putting it back.

You need to find out if the switches are normally open or closed, that can be done with an ohm meter. Then bypass each one at a time either by just disconnecting the switch or by putting a jumper wire between the contacts (wires off switch). For example the seat kill switch is normally open while operating (no connection) it closes (makes connection) when seat is raised (rider off) and grounds the ignition to shut down the motor. Hope this helps

Once having the same problem with the B&S engine, I had to replace the ignition coil. When it is in the process of failing, it acted as you describe.

either the seat or blade sensor switch is bad or unplugged. all newer mowers have a saftey feature. if you get off the seat while its running with the brake off it shuts down.my new cub shuts down if the park brake is off and you get off the seat, the blades dont matter.

ck for water in fuel sometimes we get bad gas.

It might not be disengaging the mower deck all the way off. I had this problem on an older model.

I have a 927 series rider and just put a new battery,and spark plug.Has spark and still wont start. What else can I try?