1977 55hp lower unit removal problem.. help

stillinne2

Cadet
Joined
Feb 27, 2011
Messages
17
i have taken the bolts off and the shifter linkage loose from under the power head, but for the life of me, i can not get this thing off.. any ideas?
 

Joe Reeves

Supreme Mariner
Joined
Feb 24, 2002
Messages
13,262
Re: 1977 55hp lower unit removal problem.. help

You've probably taken off bolts that were not designed to be taken off.

The only bolt that needs to be removed is seen and removed/installed from the port side of the engine at the shift rod area. It is a 3/8" hex head shoulder screw that has a regular screwdriver slot in it.

Use a long 1/4" drive extension with a 3/8" universal (flex) socket to loosen and tighten that screw, and a mechanics flexible grabbing tool to pull it out of there plus getting it back in.
 

stillinne2

Cadet
Joined
Feb 27, 2011
Messages
17
Re: 1977 55hp lower unit removal problem.. help

thanks joe.. but that is the one i did take out, the one that directly holds the rod to linkage.. and its a 7/16 lol this lower unit has not been removed in ten years from what i was told, so im sure the drive shaft is rusted.. just wondering if any ideas to get it loose..
 

Joe Reeves

Supreme Mariner
Joined
Feb 24, 2002
Messages
13,262
Re: 1977 55hp lower unit removal problem.. help

The 7/16" bolt is not a shoulder bolt, it is a regular bolt that holds the clevis to the main horizontal shift linkage. Now, look at the port side of that clevis for the 3/8" bolt I spoke of.

If you have a 7/16" shoulder bolt in there, it doesn't belong.

How far did the lower unit drop down?
 

stillinne2

Cadet
Joined
Feb 27, 2011
Messages
17
Re: 1977 55hp lower unit removal problem.. help

yes joe.. i didnt take clevis loose.. took the bolt out facing port side in the clevis that holds the linkage to clevis that comes up.. i can move linkage from lower part and move it up and down freely.. just can not get lower unit to slide out.. it twist a little. just wont come down.. im about to just go buy case of my favorite beverage and stare it down...lol
 

stillinne2

Cadet
Joined
Feb 27, 2011
Messages
17
Re: 1977 55hp lower unit removal problem.. help

sorry joe.. the lower unit didnt drop any.. thats why i think its rusted
 

rolmops

Vice Admiral
Joined
Feb 24, 2002
Messages
5,518
Re: 1977 55hp lower unit removal problem.. help

Did you loosen the bolt that is under the trim tab?
 

stillinne2

Cadet
Joined
Feb 27, 2011
Messages
17
Re: 1977 55hp lower unit removal problem.. help

yes roldmops,, got it.. i can move it side to side about an inch. .just will not go down.. can barely get a screw driver head under it though
 

Joe Reeves

Supreme Mariner
Joined
Feb 24, 2002
Messages
13,262
Re: 1977 55hp lower unit removal problem.. help

Hmmm, I'm going to double check my books to see if there's such a thing as a 7/16" shoulder bolt in any of the shift rod clevis linkages. I just don't recall one at the present.

I assume you've removed the trim tab and checked to see if there's a retaining bolt under there. If so, only thing to be holding it would be the driveshaft splines frozen within the crankshaft splines.
 

stillinne2

Cadet
Joined
Feb 27, 2011
Messages
17
Re: 1977 55hp lower unit removal problem.. help

thats what im assuming joe.. so any ideas how to unfreeze them? lol.. yeah i know, wiggle wiggle wiggle.. heck , a buddy of mine already broke the cavitation plate a little.. so ill be welding that back on when i get it off....so much for an hour job.. wow!!
 

stillinne2

Cadet
Joined
Feb 27, 2011
Messages
17
Re: 1977 55hp lower unit removal problem.. help

well joe.. 6 hours later.. yes 6 hours..lol.. well ok, took time to mix a drink here and there and stare at it a bit.. i got it out. wow.. the guy wasnt kidding when he said he didnt change impeller for 10 years.. what a mess that was.. it was a mess in there, made a mouses nest seem clean..lol.. just alot of prying and using wood wedges to get it to break loose.. I cant complain, got this motor cheap and it runs like a champ.. just didnt pump water as good as i wanted it to, and after ten years.. surprised it still pumped it period. thanks for your replies and help joe.. did you ever find out if that bolt was the original.. it looks like its the right one. everything fits snug in it , like it should..
 

Joe Reeves

Supreme Mariner
Joined
Feb 24, 2002
Messages
13,262
Re: 1977 55hp lower unit removal problem.. help

Well, congratulations on getting that driveshaft loose. Be sure to clean the splines up, install a new O ring and plenty of grease.

The 7/16 hex head shift rod shoulder bolt? Yep, checked into it and you are correct. The early bolt was/is indeed a 7/16" hex head bugger. I even checked some of the later year models in that horsepower class and they too are the same bolt. The higher hp models use the 3/8" hex head bolt.
Strange that I didn't remember that.... and stranger still that I still don't recall it. But what the Hell, at 78 years old, so I forgot the hex head size of one bolt, look at all the ones I remembered :)
 
Top