I recently purchased an aircraft running a Rotax 912 UL. The last owner replaced the stock Rotax regulator/rectifier with a Key West model after it died (http://www.aircraftspruce.com/catalog/eppages/keywestregulator.php). The Key West regulator died about 100 hours later. I installed a new one, but immediatley noticed that it runs really hot, even though the current draw was only 5 amps. I spoke with the engineers at Key West today and they informed me that their unit was designed for the Rotax 2-strokes. They said that it will not work on the 912 because the generator was designed differently. Can someone explain the differences between the generator on the 2-stroke and 4-stroke models? I believe it specifically has to do with shorting the lighting coils vs not shorting them.
