Pitman Box failure

[hardpan99]

I recently had my pitman box fail while mowing with the No7. This is an aftermarket type with the pitman box connection sandwiched between two plates around the bearing. At the time of failure the the box connection bent to 45 deg and the “sandwich” nearly came off the bearing. This mower was refurbished in 2014 and has seen about 50-60 acres since. One thing I noticed when new was that the knife head connection was (and is) so tight that the play allowed by this type of pitman box is not forcing the wear to happen at the knife head where i’m assuming it should. During operation it always wanted to sit at a slight angle so that the box connection was not parallel to the face of the flywheel as you can see in the photo. I think this condition slowly got worse until it became the point of failure. When I took the assembly apart I also noticed that the hole through the bearing is slightly off center. That might not be a big deal but doesn’t build my confidence in whoever is making these. Also I think the spherical outer diameter of the bearing which allows the “sandwich” to swivel seems to be a design flaw.
I take good care of my equipment and check the register and lead periodically. Are all aftermarket pitman boxes of this type are are there other designs? I’m thinking about going to the original IH greased bushing.

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