I have a Volvo MD2B. Today, as I approached my slip, it would not go into reverse. It is an MS (mono shift). I know it is the transmission because I disconnected the cables and could move it by hand to forward.but not reverse. Anyone had this problem and know how to fix it? What kept this from getting ugly was something an old sailor once said, "docks, like young ladies, should be approached slowly".

Fixed it. The forward-reverse cable attaches to a plate on the top of the transmission. Forward rotates the plate counter clockwise, reverse rotates it clockwise. Slightly forward And above the rotating plate is the short water hose from the water pump to the rest of the engine. There is a hose clamp on each end of the hose. For the last few trips it appears that the plate has slid under the screw of the hose clamp on the water pump. Going into the slip the other day the plate Hung up on the screw and when I applied more pressure  the clamp moved just enough that the plate could not move forward. Turning the hose clamp around cleared the plate. Everything works fine. I am not buying a new transmission.