450D Broken Bolts in Mounting Frame and Cross Bar

[PropaneTank]

Picked up a relatively low hour (approx 3100) 1986 450D. Machine is in mostly good shape but has been sitting, so I'm in the process of replacing all the hydraulic hoses.

I did find a broken off bolt in the left side dozer mounting frame, and 2 of the other bolts stretched significantly. When I tried to back them out (after heating well and then letting them cool, both heads broke off.

I'm pulling the frame piece out so I can get the broken off bit out, and then will need to torch out the stubs of the broken ones on the lower portion.

I'm thinking about drilling out the threads entirely so I can just fully through bolt with grade 9 bolts; I don't like the way from factory the bolts just thread into tapped holes in the frames.

Anyone seen this before / any thoughts or tips? Will get some pics shortly.

[PropaneTank]

[PropaneTank]

I also found 3 of the 4 bolts on the rear cross bar bracket have heads broken off. Considering whether I should try to pull all these off (everything is pretty firmly together right now) or just weld the heads to the brackets for now and if they break off then pull it all apart.

Not looking forward to drilling 4 3/4" diam holes upside down.

[Mikeforester]

Hi,

I've had experience with the cross-bar bracket bolts (2 on my machine were broken when purchased). My intact bolts came out easily with a little heat on the bracket around the bolts, some penatrating oil, and an impact wrench. The bracket needed a little heat to break the bond with the sheared bolts along with some persuasion with a hammer and steel wedges. Once I had the bracket off I welded nuts onto the broken bolts, more oil on the threads, put the breaker bar on and worked them back and forth until they spun right out. Wasn't really all that bad of a job.

Mike

[jsal]

I would use a rose bud torch to completly heat red let cool on its own might have enough out to turn out with pipe wrench or weld nuts on after heating