I have a problem with my Alpha drives shifting out of gear when the boat is running in the water. They shift with no problem when the boat is running on the trailer hooked to a hose. Any ideas whats gong on?

alpha drives use a micro switch to momentarily kill the engine . its located on the bracket where the forward cable connects to the lower cable going to the drive . its poss 1 of 2 things . 1 the swith is bad or 2 the lower cable has to much drag on it and trips the switch . very common to be the lower cable . it will always shift good on the trailer as the prop has no load on it . hope this helps

start with the shift cables.

Thanks Guy's,
I've already done the switch's and the lower cables, any idea on where to look for the extra drag on the cables?

if the engine is not dieing when you shift , it is not the cable. check the micro switch for proper operation, with it on the hose lift up on the shift bracket, it should kill the engine, if not it is the switch or adjustment or wiring.

If the engine is dying even with a new cable, It's still most likely the cable... I've personally had issues with aftermarket (Sierra) Alpha shift cables. It seems when they crimp on the brass cable ends, the crimp can be too tight causing too much drag. Also an improperly routed cable can cause drag setting off the shift interrupter switch.

I've found you MUST use the Merc cable for this application.

Good luck,,

Kurt

try lightening up the spring on the piece that activates the micro switch, it sounds like things are working to well and not activating the shift interupter, does it kill the engine when you activate it by hand.