Last weekend dug a drainage trench, with the 931B/backhoe, about 400 to 500' long and was lucky the ground wasn't too frozen with the mild weather we've been having. I had one spot where it was but went back in the trench and changed direction a bit and it was easier digging. Today I went out and did some rather minor digging and noticed something happened to one of the stabilizers. I got off and took a closer look. The pivot frame on one side ripped right off from around the bushing. I could see a couple small spots where there was a fresh break in the weld but around the rest of the weld appeared to be rusted so I think it may have been developing for some time. I think that the Cat welding procedure contributed to the failure because a few years ago the top plate of the swing post ripped off and cracked all the way around the outside edge of the weld. The break today left a little weld on the plate but I wonder if putting a hot fast weld in without any preheat may have had a bit of a quenching effect on the steel. Thankfully I was able to lift the stabilizer and get the machine back inside my new pole shed. Now I'll have to get the welder running again and fix it but I don't know if I want to do it in the cold. I guess I'll see what the weather does. Cat didn't put much reinforcement around where bushings are welded. They cut a hole in the plate to put the cross bushing for the stabilizer but there's only about a 1/4"-3/8" of meat around it and it just ripped right off. The plate looks to be 1/2" so you'd think they go at least the plate thickness. I'll put a bevel on it when I weld it so it will have some extra reinforcement and penetration. At least it's not as bad as the swing post ripping off but still a pain in the butt to have fix it.
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