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1977 120 hp Mercruiser lower unit removal when it is not in forward gear

Imperial Mac

New member
I recently loosened all of the nuts and bolts of the lower unit to the upper unit on a 1977 120 hp Mercruiser without putting it in forward gear. I did not remove the entire outdrive form the boat. Now, the lower unit is separated from upper unit by about a half an inch, but it will not separate any further. It seems it is catching on something. I just wanted to inspect and replace any water pump (impeller). Thank you in advance.
 
did you remove the side nuts completely?


Thank you for replying. Yes. All nuts are removed. It slides up and down within that half inch very easy, then it is catching on something.
Now, I cannot get it to meet the upper unit. It is in between going back on, and coming off.


Merc Lower to Upper.jpg
 
Looks ;like a can see a side nut in the upper housing???????????
Check to see if the brass foot is resting on the upper unit . Someone may have forced the units together before aligning the shift shoes
 
Everything seemed to be fine before I did not put it in forward before removing all of the nuts and bolts.

I'm not sure how to check the brass foot. I am a first timer, trying to follow online instructions.
This picture shows that the nut is actually a stud with a background to make it appear like a side nut
Thanks again.

Cropped to show stud.jpg
 
IF the brass shoe is jammed on the lower splined shaft meaning you raise the lower unit and it goes up, and when you lower the unit it goes down your options are limited.
Using wood wedges drive the unit apart, this may remove the lower shift shaft at the same time . Not a disaster.
Same page in the link only left side "F"
 
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