I have a Murray Select 13.5 HP riding mower Model No. 405000X8F with B&S 21B807-0296-E1 date 2/10/2005. It cut off after about 5 minutes of mowing and would not restart. The motor would turn over real fast. It had no spark. Changed spark plug and put on an armature/magneto/coil from another mower and it ran good. Purchased a new coil and replaced it. Then it would spin but not run. No spark again. Replaced new coil with the old one that had been working and it would still not run. Now it will run if I remove the small wire from the bottom of the coil. I checked the ignition switch and it checked good with a meter according to the wiring diagram. I cut the wire from the M terminal at the rear of the ignition switch and it would run with the wire still attached to the coil. I then ran a new wire from the ignition switch to the coil to check to see if the wire between the ignition switch and the coil was bad and it would not run. I am assuming all the safety switches are working properly since it will engage the starter,but I am not sure if that is a correct assumption. Could it be a bad ignition switch, even though it checked good with a meter, or could it be something else. Any ideas on what to check next? The fuel shut off solenoid seems to be working correctly and will shut the engine off in about 2 seconds after turning off the ignition switch.