I have a JD450B and threads are ruined on the track rail where the front crossbar attaches, any suggestions?
you got pics?
It's difficult because the front crossbar is under the dozer. There are (2) 3/4"x2" bolts that hold the track frame to the front crossbar (it's the same for both sides) The threads are stripped on the track frame. The track frame is held via the crossbar.
Actually there is 6 bolts on each side, 4 through the top and 2 through the side. I think it is really supposed to be 5/8"x 2" bolts that go through a top hat bushing that lets the bar float [rattle] when in operation. The 2 horizontal bolts are 3/4"x 2". If stripped out, a Heli-Coil would be my first choice, Keenserts would be my second choice. I would use a grade 9 bolt like a TruTorq Lawson bolt to replace the bad bolts and torque them tight. I did this to mine and it has been trouble free so far.
The B had 5/8" bolts and the shoulder bushings, so did the early C's, the update to the "Rigid" crossbar they eliminated the bushings and used 3/4" bolts. Apparently the two on each side that came in to the crossbar from inside the track frame were always 3/4" Gr8 and continued to have shoulder bushings. I seem to remember you can access the inside of the track frame, might have to drop a roller, and put grade C locknuts on longer grade 8 bolts. Also saw a lot of them welded down.... and then cracked out.
Forget welding like Lantraxco said, it will waste your time, rods, and ruin a otherwise good crossbar. HeliCoil or top lock nuts, put the handrail on the breaker bar and pull hard!
Lantraxco I had the same thought, rather than removing the track and then the track rails I thought I could remove the roller guard, release the the tension on the track, raise the dozer on the side with the issue, remove the roller and then insert from inside the rail a #8 or harder fine threaded bolt, lock washer and nut and attach the crossbar. Does this sound like your suggestion?
Repowerguy I got a reply from Mr. Lantraxco and I had the same thought, rather than removing the track and then the track rails I thought I could remove the roller guard, release the the tension on the track, raise the dozer on the side with the issue, remove the roller and then insert from inside the rail a #8 or harder fine threaded bolt, lock washer and nut and attach the crossbar. Does this sound like your suggestion?
Yes, no guarantees but I seem to recall that was how we did it back then. Good luck with it!
I'm pretty sure you can use nuts on a 3" long bolt but be aware that taking off the rock guards and a roller or two for acess has its own perils in that you may twist off a bolt or two or more getting to the job at hand. I'm not saying don't do it, just be careful and go in eyes wide open (with safety glasses on)! Often people put too long bolts in and being fine threaded it will often tear threads out taking out the guard bolts. Just my opinion!
Thanks for your thought, is it my understanding that I'd have to remove the track and remove the track frame if I were to try and insert the Heli-coil method? Regardless don't I have to remove the upper (4) bolts to separate the track rail from the crossbar. Do you have any good suggestions on removing any of the frozen bolts, I'm really nervous about breaking bolts.
I have never tried it, but I would say without the bushing in the way you could drill out the hole and retap it to helicoil size and leave the bar in place. I am not trying to dissuade you from using nuts and bolts ,I just wanted to tell you that you might make more trouble for yourself dropping a roller down for access. If you need a new roller, then that's another thing. Maybe a place for a new thread, but I use 50/50 acetone and atf for pen. oil, best in my opinion.
Must be ESP your comments jumped out at me, so I had this local guy who does this kind of work, he came up looked at the situation and brought up all the same concerns, since this guy has experience on undercarriage work on 450s he agreed to do the work. One of his suggestions included an insert instead of the heli-coil, he felt an insert would outlast the heli-coil. He emphasized the potential problem of removing the roller guard and roller. Regardless, the hard part is tearing things apart of which he has the tools and experience. By the way I spoke with a local JD dealer whose apparently is familiar with this, I mentioned, heli-coil, insert, and or thru bolt fix, at first they said insert, 4-hours later they leaned towards thru bolt solution, regardless JD dealer required me to take out a second mortgage. I'll let ya know what we did, Thanks.