Mc-1 Crack near Prop

[Ryanlewis2010]

hi guys so i have and mc-1 aprx 1970-1972 and upon inspection of my out drive this morning i noticed a rather large looking crack posted below is this fatal and what suggestions should i be looking at thanks Ryan

 

[Bt Doctur]

Re: Mc-1 Crack near Prop

usually happens when storing the drive in the up position for the winter,the lower cannot be disassembled for any repairs.
"V" the area, some JB Weld , and repaint it.

 

[Bondo]

Re: Mc-1 Crack near Prop

is this fatal and what suggestions should i be looking at

Ayuh,... Dead fatal,.... Ya need another lower unit.....

Looks like it Froze, fulla water.....
Yer other thread is soundin' like the motor did too....

 

[Ryanlewis2010]

Re: Mc-1 Crack near Prop

But this boat has been in Fl for all its life many salt water and the block is all clean same with head so

 

[Ryanlewis2010]

Re: Mc-1 Crack near Prop

now this brings me to another question would an SEI lower work with my Merc upper?

 

[Bondo]

Re: Mc-1 Crack near Prop

now this brings me to another question would an SEI lower work with my Merc upper?

Ayuh,.... Being so old, I'd think you'll need to swap the Complete drive....

I'm Guessin' the vertical shaft in yer drive is the old course spline....

 

[Ryanlewis2010]

Re: Mc-1 Crack near Prop

thats what i figured but hey it was worth a shot so putting this on the bottom of my list till i get the floor done

 

[Ryanlewis2010]

Mc-1 lower houseing crack

Mc-1 lower houseing crack

Hi there so i have decided im not going to try and jb weld my out drive which has a crack near the prop on the lower unit.
Now my new question is would it be worth it to just change the housing i found one eBay for a 100 dollars, or with it being a 72 should i man up and spend the 1300 on an SEI unit. Which i hear don't always have the best reviews.

Specs:
1972 Mercruiser 140
MC-1 1.94 Ratio outdrive

 

[achris]

Re: Mc-1 Crack near Prop

That crack is caused by corrosion under the bearing carrier cover nut. It's not completely fatal, but it will keep getting worse, eventually leading to the lower leaking oil. It's an MC-1 drive, and as long as it's 1970 (not 1969) then an SEI lower should fit on. What the drive serial number?

EDIT: I see your signature uses the word 'replica'. Is this future boat being built by the same person who built the original? Because that is the only way it can be a replica, otherwise it's an exact copy, but not a replica.

 

[dubs283]

Re: Mc-1 lower houseing crack

Re: Mc-1 lower houseing crack

with a different housing you would have to shim the gears

unless you already have the special tools required to do so, you would be better off finding an entire replacement drive

 

[Ryanlewis2010]

Re: Mc-1 lower houseing crack

Re: Mc-1 lower houseing crack

ok so what does shimming the gears in tell

 

[Pete104]

Re: Mc-1 lower houseing crack

Re: Mc-1 lower houseing crack

More special tools, good clean shop, patience.

 

[dubs283]

Re: Mc-1 lower houseing crack

Re: Mc-1 lower houseing crack

ok so what does shimming the gears in tell

complete teardown, cleaning and inspecting all internal components - replacing all seals, water pump assy, damaged parts, etc...

setting pinion gear height, forward and reverse gear backlash

 

[Ryanlewis2010]

Re: Mc-1 lower houseing crack

Re: Mc-1 lower houseing crack

OK So basically if i really just wanted to say i did it i could because i have almost anything a professional shop has minus all the special tools. but he ill at least check the parts and see what i can get for them on ebay.

 

[Ryanlewis2010]

Re: Mc-1 Crack near Prop

ya when ever he retires im going to have him help me build it, he built it in his basement in vt and ended up cutting a hole in the wall to get it out lol. I have no clue on what the serial is cuz they got rid of most of these things. (idc cuz at-least i have my title, sucks for the guy who lost his boat)
edit: Where would one find the serial just in case it might be there