help 1975 85 hp model 85esl75

[msmoth]

would not go in reverse. took lower unit apart and replaced seals and such. put new gear oil in. did not see any other problems. put back together. started motor and used remote shift. when i shifted to forward, the remote shift would lock in that position and not move. after i turned motor off, and took remote shift apart, i could get shift to move. When I started again, same thing happened. any ideas on what could be wrong

thanks

[boats.net]

Remove shift cable from outboard and check that is works with control box, remove gearcase and check that can shift gearcase into all gears if can then check shift shaft alignment when reinstalling gearcase.