1986 Glassstream, 120 chev, alpha l. Getting my boat ready for the water after winter storage. I had the outdrive half way up in storage, and when I pushed the down button on the throtttle handle it did'nt move. I then used the trailering switch to run it all the way up and it went up. When I pushed to go down, it only went half way. When I pushed the up switch on the handle it did not move. Only the down switch on the handle and the trailering switch work for half way up and down. Can anyone tell me whats wrong and how to fix? Thanks, Jerry