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lower unit crack

C

coryv4

New member
i have a older id like to say early 70s? johnson 40hp super quiet. it has a nice crack in the housing around the prop as you can see in the picture below. my question is. if i take that bottom part of the housing off, im not going to have any gears bearings or anything else fall out am i? ii have a tig welder and am certified aluminum welder so i just figured id take it off weld it from the out side then weld it on the inside and grind the inside weld smooth. the reason i want to take it off, is because i dont know how many of you know about alum welding but the oils and contaminants on the inside will cause the alum to bubble and spatter and i dont want that getting on the seals and in the bearings.


IMG_20130831_150104_170_zps29d8e950.jpg
 
I have done some aluminum welding and brazing as well.-----You are right about oil being a problem.---------The problem with this motor is that water got in and froze and hence that crack.--------This lower unit needs to be taken apart for a full inspection of all gears and bearings due to them sitting in water.----There is more to it than being able to weld that up !
 
Dropped from where... a ten story building? I've never seen one crack like that.

Don't bother trying to heli-arc that crack as the internal clearances have been disturbed. Just pick up a good used lower unit or empty gearcase somewhere.
 
joereeves said:
Dropped from where... a ten story building? I've never seen one crack like that.

Don't bother trying to heli-arc that crack as the internal clearances have been disturbed. Just pick up a good used lower unit or empty gearcase somewhere.
Click to expand...
ok he didnt necessarily drop. i was suposed to weld a crank case for his sled. he was borrowing the motor at the time and we got into an argument, i tossed his case on the bench and said get my f'ing motor off your boat and peeled out of his driveway. this was earlier this summer and the motor did not have a single crack in it. the next day i go over there to get my motor and i got home and bolted it on my boat and was cleaning it up when i noticed the crack.i called him and asked him where the crack came from, he told me he "dropped" it. i highly doubt thats what he did, but the motor was not cracked when i gave it to him and it was when i got it back. unless he put it in a freezer over night the crack is not from freezing water.
 
Whatever the argument or cause, you asked a question and deserve an answer. You asked if anything is going to fall out. The answer is, yes they will if you allow them to fall out. Once you remove the skeg the prop shaft and all the gears and bearings are not being held in there by anything other than gravity..................and the motor (or gearcase) will have to be upside down for that to happen. That skeg will also have to be properly cleaned and a new spaghetti seal installed before reassembling.
 
that is half true...if you are careful and don't rush the the clutch dog yoke will hold the shaft and gears up in there. or you can remove the prop and take the gear case bolts out and hold the bottom of the case and with your other hand hold the prop shaft and when you lay the case down you got your hand to hold the stuff up so it doesent fall...you can even replace everything with the motor upright but it all depends on how worn your yoke is....
 
Crack is from the inside.

Obvious.

Poor thing has been neglected obviously.

Get an act together and sort it out or BIN IT.

Post some pics, we all love pics, if you are fixing it up aye.

Help accordingly along the way of course.

B
 
i flipped the motor pulled the case off. took down some of the surface on a mill welded it and ground it smooth. i will post pictures later. it bolted right back on without a hassle or miss alignment.
 
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