Tommy, when your rotor slows down, is it just the rotor slowing down or does the fan speed slow down at the same timeIJ If the whole machine(separator) slows down in general when the rotor slows down I would suggest looking at your separator clutch. Pull the dipstick on the gearbox behind the engine. If the oil smells burnt(believe me, it will have a very DISTINCTIVE smell),your clutches in your sep. clutch are burnt up. Another thing is to drain the oil out of that gearbox, remove the filter for the sep. clutch, and cut it open. A burnt sep. clutch will leave lots of fiber pieces, meaning clutch plate material, in the filter. Good luck.