Lower Housing Cracked 1957 Big Twin

[david-bartlett]

Dan,

This did not happen because you did not change the oil. That is secondary. The cause is likely clogged drain holes below the impeller. Water needs to drain out of that area after use or you will get freezing/cracking as you did. A good welder can possibly help you out, but without pics it is hard to say for sure.

Lots of good help and parts available from this group.

David

[chris-p]

Ok that is ok, I understand now what happened. I was envisioning higher up, where the gearcase meets the exhaust housing.

Most definately, that gearcase needs a reseal. The oil drained out, and water got in. Froze, then expanded and cracked it.

While every 100 hours might be ok, it should be done just before winter.

You might be able to have it TIG welded with argon, then resealed. OR, as I said earlier, just buy a replacement gearcase ready to bolt up. That would be the easiest, and likely cheapest.

Perhaps a member in your area could help out.

[danblue]

http://postimg.org/image/uq1ihpsc9/3133f579/

[danblue]

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[danblue]

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[danblue]

[danblue]

So If I can just fix/replace the shark fin housing assuming the gears are OK which I believe they are, wouldn’t that be enough? I don’t believe I would need to replace the gears, etc.

Any details are greatly appreciated! Thanks everyone!

[frankr]

Wow, that’s an unusual looking crack. But since it obviously had water in it to freeze, the question is how much water damage is there to the gears and bearings? Only a tear-down and inspection will tell.

[danblue]

Understood. I do remember when I drained the old oil out of it when I bought it, The oil was a bit milky..perhaps the seal that is between this lower unit and the above unit was bad thus the leaking…I really don’t know how these things work.

I guess I will take the shark fin housing off of my 1956 Johnson 30hp Seahorse, and bring it to my outboard guys for an inspection and fix…I don’t rust myself to get in there and work on it. I will tell you all that the motor has always run really, really strong if that helps matters..AND there is oil down in that thing, so I just don’t know..I guess all the oil leaked out during last season…any other advise is much appreciated!

[danblue]

So, if the gears/bearing are bad with this, can anyone help me with the purchase of anything new I will need? If there is a way that I could purchase a ready to go refurbished unit for my outboard guys to install, that would be great!

Thanks!

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