I posted this elsewhere without any answers, so I am reposting here.
Any reason my drive would stick in FWD? I can sometimes get it out using some force on the shifter, but sometimes I had to shut down the engine and then it shifts back to neutral. Shifts to reverse and back to neutral without any problems. Appears to work fine once in drive, but wont come out. New boat to me. Only been out twice on it. Kinda did it the first time out and then was a real issue this last time. Docking is really not fun.
BBC with B&M
Probably about 1989ish year.
twin engine boat
Experienced this many years ago. As I remember there are 2 likely causes. Shift interrupter switch not functioning or shifter cable in need of replacement. Added resistance in an old shifter cable can cause the interrupter switch to not function properly and a new one was the fix in my case.
Sorry I can't offer more beyond that, but I'm sure there will be more help soon.
Experienced this years ago myself. As you say it will shift when the engine is not running, makes me lean as per Budweiser's comment.....the shift interrupter switch not functioning. That was my issue and an easy fix