Re: cant get lower unit back on 86 dt85
Ok now I understand what you are doing.
These shift cams frequently pop out if great care is not taken.
Yes the propshaft/gear assembly has to be removed. There is a spring loaded ball which runs in the detent on the back of the cam. When the cam is removed this ball and spring pops out of the housing and prevents the cam being reinserted.
Unfortunately the aluminum case and the studs corode and weld together. You may have to use heat around the studs and casing to free the casing.
In any event you will probably need a puller.
This is what I fabricated.
A strong piece of angle iron, 1.5 inches or bigger, about 10 inches long. Drill a hole in the center of one face of sufficient size to fit over the prop shaft threads. Two lengths of 3/8 threaded rod and four nuts. The length of each rod must be longer than the prop shaft. Cut a 'V' into one end of each rod to fit around the case edge above the housing ring and around the Skeg edge below the housing ring. Drill two holes in the iron to accept the rods spaced so as to line up on the case and skeg. Use two nuts on each rod to hold the rods in position in the iron and the rods pressing on the casing and skeg with the iron fitted over the shaft. Keep everything square. Using the shaft nut try tightening it to apply pressure. If your lucky this will be enough to free the shaft assembly. If not then careful application of heat at the stud areas and around the casing, with the pressure applied, should do the trick.
You will need to replace the large seal 'O' ring. Hopefully the shaft seal is still in good shape. If not, this is the time to replace it.
Good luck.
