Frozen bolt removal

Hello all,
got a rather basic repair issue here. working on my Deere 455G. the top roller on the LH side was squealing constantly. I removed the roller and sure enough, no oil (looks like for quite a while). one bushing was not too bad, the other is totally worn. The mounting shaft has a pretty good groove worn into the top. I was going to attempt to press out the shaft, rotate it 180 degrees as that side has very little wear. I am thinking since all the load is on the top section, I might be able to get away with it, using new bushings. Thoughts on this fix?
Now for the "rest of the story". the bolts that hold the top roller mounting piece are REALLY frozen. I tried heating with MAPP gas for quite a while (10-15 minutes) then tried the 3/4 impact and 36" breaker bar and nothing. since the bolts are long (m20 x 55) and there is not a nut on the other end, looks like they thread into the track frame, I am trying not to break them off.
any thoughts/advice? Do I need to stay on the mapp gas longer or do I need to muscle up and go get a longer pipe? I would have cut them off by now, but I really want to avoid a broken bolt extraction.

Thanks!!!!

Oh, boy! There's a lot of bolt extraction know-how on Youtube, so take your pick.

Did the heating get the area a dull red? Also, after heating, as it cools down you can try to put penetrating oil on it (once it is cool enough to not vaporize the oil) in the hopes that a little will get drawn into the threads.

Keep the heads on the bolts- go for a 6 point socket and a long bar. The bolts "should" be of tough stuff and stay together. Once you cut the head off you don't have much to work with.

I've ended up just drilling them out and cleaning out the threads with a tap. This depends on getting the drilling pretty close to centered, tho. And no room unless you have the track broken....?

I'm sure you will get lots of suggestions for this--one of them is bound to work for you!!

Photos and comments are expected!

Jon.

use a longer pipe, if they break off, weld a nut to the bolt, let it cool, and it will turn out much easier.

Some good advise above. If you have time patience does help. Take a little time and get the entire bolt head dull red and let cool. Every thing expands and contracts differently that breaks the bolt free. If you have time spray penetrating oil on it every now and then, reheat to cherry red a few times take a few days if you have them. Use a 6 point and a impact, you can run it forward and back to work it loose, taking it out in one piece is much nicer. Don't crank a big impact up too much you will break the head off. You have better feel with a breaker bar. I like an impact.
Best of Luck

I agree with the heat cycling and the cycling with tighten/loosen as well.

Seems to me I saw that work on YouTube with a guy going after frozen exhaust manifold bolts.

Jon.

The head of the bolt can be rusted solid to the surface, I take a brass bar and a mini sledge and strike the bolt straight on to shock the head to loosen it. The heating of the head and not the surrounding area swells it and breaks it free.

I put enough never-seize on new bolts to get some under the head. Easier to tighten and remove.

Thanks for the advice. So I went BIG. borrowed an acetelyne torch, got those bolts cherry red, and used the 6 ft pipe. I usually am working on cars & motorcycles, so I had to remember this is BIG IRON and requires BIG TORQUE. Here are some pics. hopefully you can see the wear on the top of the shaft vs the bottom.

Thanks for the advice, it worked!!

Thanks for posting some pictures! Is the shaft a standard size? You can get ground shafting from a steel supplier and press that in. Maybe a piece hydraulic cylinder rod, used even. Capillary action helps keep the oil in the bearing. I would try for a new shaft and new bushings. Running loose takes out seals, and the oil will run out the gap on the bottom. The gap on the bottom stops the oil from keeping the shaft up on the oil film, causing premature wear on the top of the shaft. If you don't use it much you might flip the shaft over and put in a mix of 3-5% moly grease and heavy oil like gear lube. Are there seals on the carry roller? What type are they?

The local Deere dealership claims the individual components (seals, bushing) are no longer in production. However I found the OEM part numbers online along with the rear seal & front gasket. The Deere dealer does have the entire roller assembly (shaft, bushings, seals, roller) as a unit still available. Since I will also be tackling the other side, I went both routes, ordered the individual parts and the assembly. Figure I will go ahead and install the assembly on the LH side, and hopefully the shaft on the RH top roller doesnt have this kind of wear, so I can reuse it along with new bushings and seals. Fingers crossed. Manual says 80/90 gear oil (GL5) for the top roller. looking closer at the shaft, I am becoming less comfortable with the depth of the groove cut by the old bushing. I will check the amount of play/gap when I get the new bushings, right now, not too confident there is enpough left of the old shaft. I also noticed the roller itself has a bit of a "ledge" or wear on one side but not the other. I am getting the feeling the roller may be at the end of its useful life, so maybe just replacing the entire assembly will be the easiest and most reliable repair. This unit was claimed to be owned by a local municipality, so I have to believe it was "run hard and put away wet". I will say, for an old loader, this thing is a blast to operate. I am going to really rearrange the landscape on the farm