Alpha lower unit question

[270win]

I'm replacing the impeller in my 84' Alpha drive's lower unit. All the lube is out and thankfully looked great, but I'm having an issue with removing two nuts. All of the other nuts and bolts came free no problem, but the two bolts under the cavitation plate right above the prop are of odd size. I tried 9/16, too small, 5/8 is too big to go into the recessed area where the nuts are, I tried 14mm and that's too small but 15mm is not working either. Is there a special socket for these? I've never ran into anything like this working on my previous Alpha drives. Any input is welcome.

 

[CliffA]

I'm replacing the impeller in my 84' Alpha drive's lower unit. All the lube is out and thankfully looked great, but I'm having an issue with removing two nuts. All of the other nuts and bolts came free no problem, but the two bolts under the cavitation plate right above the prop are of odd size. I tried 9/16, too small, 5/8 is too big to go into the recessed area where the nuts are, I tried 14mm and that's too small but 15mm is not working either. Is there a special socket for these? I've never ran into anything like this working on my previous Alpha drives. Any input is welcome.

you likely have the generation one Alpha drive...i had the same drive on an '86 Chris Craft....i did not have to purchase any special tools to take the drive apart when i replaced the impeller....i don't remember the size sockets i used but i remember it being a pretty easy job....it may be that the corners of the nuts have been rounded off when someone removed them before....i would suggest you soak the nuts with PB Blaster for at least a couple hours and try again with the best fitting socket you have....if that does not work you could buy a cheap socket that is slightly smaller than the nut and drive it onto the nut with a hammer...this should allow you to remove the nut but you will sacrifice both the socket and nut....the nut is a standard size so it should be easy to replace....

good luck...

cliff

 

[270win]

Thanks, I've got tools that will remove the nut and destroy it in the process...I was hoping to just be doing something wrong or needing a special tool.

 

[src]

They sell thin-walled sockets that fit into tighter spaces. I know you can get them at Sears (Craftsman) among other places.

 

[270win]

Yep, I was using an impact grade socket, my thin walled 5/8ths did the trick.