I just replaced ALL the rollers on one side of my D6 9U project. And one on the other side. Be aware ... Those roller bolts will probably not just come right out of the frame. I had to replace the bolt strips inside the frame. Doable. But not fun.
If the flat spots on your roller match the tracks, it's probably seized. And if It has flat spots , it's touching the rails\tracks.
I found good used and or rebuilt rollers for $50.00 each. The hassle was installing them. Others may chime in, it may be "ok" to leave it alone. Of course that's not "right".
I cut many of my roller bolts off with a torch, after a few of them pulled the threads out of the bolts strips.
I found it to be useful to cut the old rollers off with a torch, leaving the bolt intact. This leaves the bolt head there to attempt removeal, and puts some heat on the structure along the way. Now you can heat the bolt much closer to the threads in the frame. With only one roller, take your time, heat, cool, heat cool, after cooling wack the bolt with a hammer.
I gained access to roller by loosening tracks and raising tractor up. No need to break the track .
The D8H has bolt threads straight into the frame, try them first with your 3/4" drive and a six foot pipe, if they all can be loosened, you are in luck. Dig a hole about six feet long for the track to drop into and drive over it, undo the roller bolts, loosen the track and jack it away from the rollers down into the hole for clearance, put the 'new' roller in position and tighten the track then jack it up from underneath to get the roller close enough to start the bolts.
Catsilver,
I like the idea of digging a hole. That would be easier than jacking and blocking. I have three bottom rollers on my 14A that need replaced. I really did not want to break the track. Thanks for posting this idea!
JanM
You have a wonderful day. Best wishes. Deas Plant.
Hi, Tim T.
I had to change one bottom roller onna D9G in 1971. This machine had spent 3 months in the ocean from new in 1966, covered almost completely twice a day by the 25 - 30 foot tides in that region. The rock guard bolts were all frozen so I cut away the section needed to slide the roller out. The roller mounting bolts - wonder of wonders - did come out.
This machine had a blade and a ripper and thus was capable of jacking itself up after the track had been loosened to leave all the slack down at the bottom. In your case, I think I would try reversing the right track up onto a railroad tie until the end of the tie is about at the middle of the track, probably just before roller #3 starts climbing onto the tie. It may be necessary to reverse a little further to get the rear of the track to drop down and then travel forward again or perhaps your 2 X 8-ton jacks under the equaliser bar might do the trick.
I would then consider digging the hole that Catsilver mentioned under the front of the track before loosening the track so that there is space for the track to drop down into, loosen the track off completely - grease can be a lot cheaper than sweat and hard experience - and you may even need to gently nudge the front of the track with the 'other brand' dozer to get it fully retracted. It may even be worth using said 'other brand' dozer as an anchor point to pull as much as possible of the slack in the track over the front idler and down to the bottom.
Don't rush! Time is cheaper than the cost of surgery to fix busted hands or limbs.
Just my 0.02. Hope this helps. Happy fixing.
I like the idea of digging a hole also.... I even have a mini excavator and loader with forks to help me. I can get a couple used rollers from another 8H also. Sounds like a summer project right now... If I do run it some and I keep an eye on it, what damage does this do to my rails... I would not think very much?. I have seen dozers run with frozen rollers for many hours before the company decided to change them all. I will only put at most 50 hrs a year on this thing...I think. Most of the time I don't think this roller is even touching the rail much. All the other rollers look 100% better. Like maybe they had frozen bolts and skipped this roller during a previous change out??. Seems strange. Also this machine has the usual mix of double flange and single flange rollers. the bad one is a single. Thanks again for the info and ideas, Tim.
I ordered a new roller for it.... found that I can get a new aftermarket roller from our JD dealer...for cheaper than I can get a new OR used one plus shipping. No shipping to the JD dealer which is half hour away...Best price too.Hard to believe. He "customer support man, who is a great and knowledgeable guy" said that one new roller on that big thing won't matter a bit as far as not matching the others. I think they are all mixed anyway. Most are very good. Also I bought a Cat roller lubricator nozzle to fill my other rollers. Found one brand new..and its even an original Cat tool for cheap. "25 bucks"
This JD/Hitachi dealer, as far as I am concerned has been fantastic to work with. I did all my bottom rollers on my 450C last winter... better price than used rollers and no shipping. They also put a seal in my track adjuster on that 450 and short tracked it,"which I decided not to do myself" at a price that was more than fair. Great field mechanic also, fast and GOOD man with 25-30 years on the job. Undercarriage wise they say they will work on anything, not just JD. Track shop too.. Nice to have a good dealer like that near by. I will try to change this one myself... I am figuring that the previous owner did use zinc on the bolts. They have a reputation for taking good care of there iron.
Which dealer is that Tim? I have Lakeland JD here in Rochester but I don't think they're track machines - just mowers and wheel tractors
keep that old roller and rehab it in your spare time--did that to a couple on my D2
Someone here can surely help on this suggestion:
Loosen Track adjustment, put block against sprocket (in top front of sprocket, cat in reverse) to pull front idler back and chain it in that position. This will allow all the slack possible in the track.
One should be able to move the machine on surface enough to allow track slack at roller. Be careful moving the machine, you don't want to throw a lose track!
Been a very long time since I was in the Cat shop.
Just remember -- as many others here have stated -- NOTHING IS LIGHT ON D8, that iron is not forgiving to misplaced hands and limbs.
Good Luck