I replaced the stripped gears on my Craftsman Garage door opener. My opener would not work. It rotated in 1 direction for 2 seconds, reversed for 2 seconds and stopped. The chain was not connected and the limiters never hit the stops. I removed the PLASTIC CAP on the shaft for the RPM Sensor. I cut it FLUSH with the Lock-ring so it would engage further. Re-installed it and now it works perfect. My Force adjustments are at the lowest level, and there are no more problems. Kenny