I took the boat out today, and put it in reverse to leave the dock, and it engaged into forward. So forward works and engages forward motion, and reverse engages into forward motion. Its a 1978 mercury 1150 outboard. Any ideas on how to fix it?
Remove the gear case again. Neutral will be the middle on the detents you feel when you turn the shift shaft. Prop will spin freely. Put upper motor in neutral. You should now be aligned for reassembly.
Yes, you need to remove the unit again... Set the lower in neutral as described so that the prop spins freely. Then set the upper in neutral via the controls.