1963 65 horse mercury bottom end stuck

I have a 65 horse merc that I

I have a 65 horse merc that I have been having a lot of trouble with. A friend tried to help me with it and we tried to remove the bottom end and check it out. we put it in gear and removed all the bolts acording to the book and it seemed to be stuck where the studs come through. we hit it with a mallet and you can see daylight at one end but it seemes to be stuck at the studs.there is a slight crack im going to have to have welded if I can ever get this thing off.
is there anything that will help break up the corosion that I can spray in the stud area or some other solution you can help me with im loseing hope

It may be that the drive shaf

It may be that the drive shaft is stuck in the crankshaft (rusted). Lay the motor on the ground and hold the block with a flywheel puller .Hold the block in position somehow ( tree ? ) Rig the bottom end with a come along .Sounds like a lot of work but using prybars will result in damaged castings.

there is a gap all the way fr

there is a gap all the way from the back ? (closest to transom)of the motor to just in line with the studs that is why i think it is corosion around the studs that is holding it. there has been alot of corosion in other places and alot of bolts got broken off when we were working on other things this motor wasent taken care of verry well

"Wayne,

If the studs are st

"Wayne,

If the studs are stuck, the best approach is to cut them with a hacksaw at the seam between the lower unit and the mid-section. Then you will have to drill out the studs carefully. You might be able to save the threads, but usually heli-coils will have to be used to provide threads for the new studs.

I looked at a parts diaqrahm for your engine, and there is a stud at the front of the gearcase. This is usually the one that is stuck, because it goes through a long channel in the mid-section.

"