Alpha one top cover bolt broken

[1979checkmate]

hey all,

i got got a complete alpha one transom and drive assembly for a song, but made a bit of a mistake. As always, when inspecting the drive I pulled the top cover to look at condition of gears and oil... I broke one of the 4 top cover bolts off in the casting. I drilled and attempted an ez-out after plenty of heat and penetrating oil.. and managed to break off the tip of the easy-out in the bolt. At this point I expect I am resigned to finding a machine shop who can help me out but am trying to fight the temptation of leaving as is. Given this is an o-ring seal and not a gasket, I expect the three remaining bolts would still be sufficient? Someone knock me into line?

 

[achris]

... Someone knock me into line?

Gladly...

That top cover also applies the preload to the driven shaft bearings. Without all 4 screws, the preload will be wrong, and the top bearing outer race will be 'cocked' with relation to the shaft... Expect the drive to last a few minutes under load....

Chris......

 

[1979checkmate]

Yep... that’s what I expected. Hopefully a machine shop can help me out, that bolt is STUCK. Expect galvanic corrosion and/or galling. Won’t make this such a great deal if I have to turn around and buy a new upper because of a broken bolt

 

[achris]

Good no cheap, cheap no good.....

(old Chinese proverb)

. Won’t make this such a great deal if I have to turn around and buy a new upper because of a broken bolt

And all the tools to set it up....

 

[1979checkmate]

Ah if I need a new one I will likely just buy one ready to go, not a just the casting-the tools as you said are expensive enough it makes no sense to buy them for one job. Still happy with my purchase and expect a machine shop will help me out. Got the full gimbal, transom and drive assembly along with trim pump and cylinders for less than $500, can’t complain too much.

 

[Bt Doctur]

your mistake was using an easy-break tool should have just drilled to size and retap it

 

[1979checkmate]

Haha, I made more than one mistake but I agree. Bolt is still somewhat proud of the surface, hoping that the machine shop can weld on a nut and remove. If not, I will get their recommendation. One of those things, I would prefer to pay a pro than spend hours and hours fixing my mistake

 

[1979checkmate]

Machine shop got me fixed up. They had a heck of a time dealing with it as well, attempted multiple times welding a nut to the broken bolt but weld kept breaking. Ended up having to cut a small relief through the outside of the case to relieve pressure and remove the broken bolt. They did a professional job rewelding and painting the case. There is of course some risk that the heat distorted slightly and threw the preload off - but for the price i can't complain and time will tell.