I have twin 200 yamahas (93's) and am having trouble with port engine. Lower controls just replaced and took for water test. Port engine idles fine but when put in gear...buzzer sounds and engine is in gear for a second then acts as though its back to nuetral. Works find in reverse. Also, works fine from upper control and of course the other engine works fine. Any suggestion why Port buzzer and nuetral seem to be stuck?