3 PT Upper Housing Crack B7610

[cuda130103]

I noted a small leak near the upper 3pt arms.(the hydraulic arms) Just a little fluid running down the housing.
It turns out it is from a hair line crack that goes from one bolt hole to the other bolt hole on the other side. This is that huge heavy cover that includes the 3 pt lifting ram. I am concerned with what caused this before I repair it. I think I can weld it. It is cast but, I don't think it is cast iron.
The tractor is new to me,so I don't know its history.
I pulled the housing off, not too difficult. You just have to disconnect all the linkages and remove the bolts.
What I found also was a broke piece of plate steel This piece is maybe 4 inches square by 1/4 thick and sits in a channel in the lower housing. I'm not sure what is for??? It just sits in there loose. It looks like it might be a stop for the 3pt Ram at its fully raised position.
I surmise once it breaks it could then move back farther and push against the housing and crack it?? But what broke it?? 3pt mis-adjusted?

Anyway.. Anybody else out there have a simliar problem or suggestions to for non-repetive damage?

Thanks

[ronjhall]

Does your tractor have a heavy duty top link bracket. Highly recommended for tractors that use heavy duty attachments. The bracket comes with a 3PH backhoe. But my dealer recommended one for my tractor because of a couple of the heavy attachments I have. I later purchased a BH. Here is a link to a thread on the B2910. Parts are simialar to your model tractor.
27-2910-toplink