I replaced the coil with a blue bosch as suggested by others. I finally got it, put it in, started right up, mowed and almost got done with the yard, then it happened again. I'm glad I didn't throw the other coil away. I will start with the plug wire tomorrow. Thanks for all the information, it makes for a good troubleshooting list. I'll let you know what happens. I also moved the coil to the helm, to eliminate heat and vibration