Hello everyone, I am new to this form, and also to skid steers. I just recently purchased a 1999 863 Bobcat, G-series, with under 1300 hours. The machine is in pretty nice shape, but I went to grease all of the pins the other day, and everyone except the bottom right bucket pivot pin took grease. I tried everything, heat, penetrating oils in the grease gun, etc. but no luck. Anyway, I realized the bushing shifted and was sticking out of the arm at least 1/8", so the channel wasn't lining up with the pin's grease hole. The bushing actually wore a nice groove into the bobtach. Because of that, it was annoying to drop down the bobtach. I decided to replace the pins/bushings/seals on both sides while I had the attachment plate down. I removed both bushings pretty easily. I MIG welded here and there in the bushing and both hammered out nicely. The bore, whose bushing wasn't getting grease, is a bit rusty, though. I lightly wire brushed it, and also lightly hand sanded it with some old 100 and 220 grit paper. I still have a decent amount of pitting, as I'm afraid of removing too much material. I am just not quite sure if the bore will be tight enough to support the new bushing. I tested the bores with the better of the two old bushings (which I shrunk by welding inside). The shrunk bushing will start to go into the side that was greasing fine, but to go further I'd have to hammer it in. But, on the other side with the more pitting, when I take the same bushing I can push it in by hand. Maybe I'm worrying too much and the new bushing will be tight enough, despite the pitting and wear. I'm just wondering if there is anything else I can or should do. Has anyone used something like Loctite, at the ends of the bushing, or something else to fill space slightly? Any advice is greatly appreciated. Thank you. Joe
Welcome to HEF Bobcat99. :drinkup I've had success cleaning everything real good and mix up a good batch of JB Weld, coat the inside of the socket a coat on the bushing, slip it in and let it sit for days to cure before reassembly. Another option for a proper repair, Bobcat sells a new weld in socket, cut the old worn socket out and weld in a new one.
Hi Willie, Thanks for the reply. I see you have a lot of great information to share, reading some of your other posts. Anyway, if the new bushing, before chilling (I plan to put in my freezer overnight), won't go in without a hammer, should I assume I'm good to go without JB Weld or Loctite or anything? Or if after chilling in just the freezer, if it just slides in, without much assistance of a hammer, should I assume it's too loose? I guess I am just not familiar with the tolerances. Now, with the 863, the bushing is in the loader arm, not the bobtach. I assume you mean that replacement socket is for the other style, is that correct? Joe
Ahh, that's like the large frame Bobcat machines, doesn't use the tapered pin, instead uses a straight pin with the wear bushing in the loader arms. I haven't had one of those worn as much as you describe, where you can simply slip the bushing in by hand, but I wager fitting it with JB Weld or some other epoxy, such as Devcon, will work just fine. The parts diagram shows two part numbers for the bushing, 6708517 looks like the bushing that you have for pin that fits into the bore of the loader arm, but it's also showing a 7109386 "BUSHING wear - bore lower pivot on lift arm to 1.8715 +/- .0005", that might be the weld in bushing that the 6708517 fits into.
Hi Willie, Yeah, exactly, it's the large frame style, with the wear bushing in the arm and the straight pin design. Just to clarify, when I say I can slide the bushing in by hand, I meant just the old bushing I removed, which shrunk by welding inside. I welded on it quite a bit, so it wouldn't be hard to push out. However, my concern is this same shrunk bushing goes in more easily into the problematic bore, than the better bore. Who knows, maybe it's only that after sanding it a bit, I removed a few ridges that I didn't remove on the good side (which I only hit with steel wool). Joe
Well, being a straight through hole bore that the bushing fits in, no real worries, when you go to install (press in) the new bushings, if one of them seems "too easy" to press in, you can always just shove it all the way through, back up and punt, go to a plan B to make a tighter/more secure fit of the bushing.
Thanks, Willie. Yeah, I figured I would just have to play it by ear. The bushing's coming in tomorrow morning, so I was just trying to work this out in my head beforehand. Just curious, under normal conditions (good tight bore), will putting the bushing in the freezer for several hours make it go in fairly easily, say with a lump hammer. Or will that not really get it cold enough to tap it in? Joe
Hard to say, sometimes it works, sometimes no. Dry ice does a better job of shrinkage than the freezer.
Or if you have access to liquid nitrogen, know some line bore people who prefer that.
Hi Willie, I couldn't manage any dry ice easily or liquid nitrogen, so I'm going with the freezer for now (or wrapped out in the snow right now). I just picked up the new bushing (shipment came late). It is definitely loose in the bore. I can put it in by hand about 3/4 of the way then it starts to get tight when it hits the area where it spun out of. So I guess I'll be JB welding it into place. The other side seems okay but I might JB weld it anyway. I have two questions, first is there any danger of the JB weld filling the outer grease groove too much? Second, regarding the seals, there was not much left to them and I couldn't quite tell their placement. I assume the face that has the full metal rim should go in, so that you see the rubber channel from the outside. In other words the rubber taper begins on the inside and goes narrower to the outside, allowing the grease to escape. It's hard to describe, perhaps one of you have a accurate picture of it done. Joe
Do you happen to have an ice cream factory anywhere nearby..? They are always a good source of dry ice.
Nige, I'm not sure about an ice cream factory, but I do have a blizzard outside, which I'll try to use to my benefit.... Not as cold as dry ice, but I'm sure it will help some. Besides, it will only be one side which I will have to worry about the bushing not going in easily, unfortunately. Joe
Another option, the parts pages shows an oversize bushing, have to bore the hole in the loader arms to 1.8715. Isn't your grease fitting in the end of the pin which sends grease through drilled holes in the pin to inject grease into the inner bore of the bushing? If so, JB Weld filling outer bushing groove is no issue. You pretty much have it correct, rubber taper begins on the inside and gets narrower as you go to the outside.
Putting bearing of that diameter in a freezer won't make hardly any difference. Dry ice is -50C and on that size won't be much better. Liquid nitrogen is -196C and on a 2 inch bearing will pull down the size 4 thou. For something like that I would machine up a dolly and drive the bearings in with a hammer. It would be worth while getting the bore measured with a mike and comparing the size of the bore with the size of the bearing. The bore needs to be a couple of thou smaller.
Hi guys, Thanks for all of the advice. I really appreciate it. I put both bushings in last night. The worse of the two bores was looser on the inside, but it still had a little bite on the outside end of it (on the side that the bushing had slip away from and wasn't rubbing/rusting it. But, I JB welded it in place. It had some uniform rust pitting, so I cleaned the bore as best as I could, wire brushing and sanding it, then I scored it a few times here and there with a file. I also sanded/scored the bushing a bit, decreased both really well with carb cleaner, and gave a good JB weld coating on both. For the other good bore, you guys are right, the regular freezing didn't do much. I was able to hammer it in with a combination of a lump hammer, piece of pipe, and the old bushing itself for final seating, but it was a little bit of an effort. I figured the lump hammer head was fairly soft (being a cheaper hammer), and wouldn't really damage the bushing. Also, I decided to JB weld this into place, just to play it safe. Although this bushing was taking grease fine and looked okay, it was shifted to the inside of the arm completely. Either it moved and pushed out the seal, or it was changed at one point and whoever drove it in hammered it in too far or simply forgot about the seal. I hope the epoxy holds well. This was actually my first time using JB weld. I'm going to give it plenty of curing time, probably a few days. I've got my wood stove working over time. Worst comes to worse, I'll have to have it bored and that oversized bushing installed. Joe
Sounds like you've done a good job Bobcat99. The JB Weld epoxy is worth a try. Depending on the application (your case) it may work just fine for a long time. But even if it doesn't, it's not like it cost you a pile of money for the effort if you had to back up and punt to do it again with the oversize bushing.
I've used sleeve retainer locktite 640. Or try having the machine shop knurl the putter diameter of the bushing if it's not too hard. As others said liquid nitrogen is the easiest, most literally fall into place but dry ice works in a pinch