Guess it's time to stop ignoring this issue. Looks like a previous owner replaced the factory bolts with some really cheezy looking stuff. The washers are very dished, and there is a lot of unhealthy looking movement when I take the weight off of the tires with the right stabilizer. I have not taken anything apart yet, but the manual shows that there should be dowels holding things in place as well as the bolts. As much movement as there is, I suspect that the dowel may be broken or completely missing. Any of you guys have experience with this? https://youtube.com/shorts/lt7Ya0iBs78?feature=share
Had a 555B years ago that had the same issue. Bolts were severely rusted and the washer were cupped like yours (not uncommon because the holes are elongated for easier alignment). The upper set of bolts are a real pain to get to if I remember correctly. Couldn't break them loose and had to Sawall them off with a bimetal blade. If I remember the bolts are 7/8". You may also want to check underneath, there is a large pin on each side where the lower backhoe arm attaches to the frame. Mine were worn and I had to make new ones. If that pin is loose, new bolts won't help
OK, thanks for the info. Not really a job that I am looking forward to, and I wanted to get as much information as possible about it before starting. Do you remember if those dowels are welded on, pressed in, or attached in some other way?
Don't remember for sure. Why is that an issue? You want to do one bolt/nut at a time. Otherwise the backhoe unit will come crashing down. Make sure you block it some way for safety no matter what you do.
I was assuming that I will need to completely remove the whole unit from the tractor to fix it properly, rather than just replacing the individual bolts. With as much movement as there is, I suspect that the dowel on that side is completely destroyed or missing. I also suspect that the hole/slot that the dowel fits into is probably also damaged. The way it looks to be designed, it would primarily be the dowels that would prevent movement, rather than the bolts.???
Dowl pins are designed not only to prevent movement, but usually are for precise alignment.
Although in this case I don't believe that perfect alignment is critical, just prevention of movement.
Do yourself a favor and buy new hardware from CAT after you get her separated. No telling where it will be made but it will be made to spec.
I watched your video. !! The bolts probably came loose and then the dowl pins sheared. Hope fully the sheared pins are still tight in the tractor frame and you can get them out. There are a couple of ways to repair the wallowed out pin holes in the backhoe frame.
Just got around to looking at your video. I now agree that the hoe has to come off to fix it properly. Those dowels may be hardened so drilling them out would not be an option. Going to need carbide or someone good with a torch, but you may get lucky and be able to drive them out
I have some time off of work coming up in about 3 weeks, so I will plan on attacking it then. I don't even have a welder or torches of my own, so I will probably end up taking it apart, then having a professional welder come out to repair the damage. Mobile welding services are generally really cheap, right? LOL