to clarify, the uneven wear marks are on the non-tapered part of the pin, the bobtach side. ... they seem to seat very well but for some reason the seal was pulled through and mashed. Maybe when I was torquing it but perhaps due to crooked seating of pin it worked itself out during the hour of use and was mashed due to developing slop (minor on my machine) on the lower end. .... what about this....... install pins without bobtach, hammer them in, torque bolts, re-hammer, re-torque and lay a straight edge between them to see if aligned. .... I'll call the dealer tomorrow too and check back in. Thanks
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I did figure that was the end you mentions that was marked, if it was the other end, i'd be concerned
Even float of the bobtach could possibly damage the seal on the pin. On machines i have worked on, i actually removed this seal and machined nylon spacers to take out the play between the bobtach and arms. It keeps the grease in and dirt out, it also stops side to side movement.
OK, my machine is at the dealer. they do have a reamer. I had the lower arms exposed when I took it in and the taper was wallowed a bit with more play on one side than the other. All in all not in bad shape........just wondering what it will cost. I'll let you guys know. ... I like the idea of spacers/shims to take out the slop of the bobtach. Tazza, I'm wondering why you used nylon, it seems like it would wear out a lot faster than metal. But then maybe it just gets pounded in tighter and tighter to keep the dirt out. ... I am going to put in spacers/shims to minimize the dirt and side to side play. Maybe that will keep the seals from popping off. ... what kind of off the shelf material will work the best? ... IceI did figure that was the end you mentions that was marked, if it was the other end, i'd be concerned
Even float of the bobtach could possibly damage the seal on the pin. On machines i have worked on, i actually removed this seal and machined nylon spacers to take out the play between the bobtach and arms. It keeps the grease in and dirt out, it also stops side to side movement.
Nylon is a lot harder wearing than you may think. I actually had a 4 in 1 bucket that had un-greased nylon bushings. THe bucket was well used and the bushing was still intact.
The other good thing with nylon is that it will wear before the metal of the bobtach or frame does.
Done! .... The dealer charged me about two hours labor to ream the lower fittings, total cost $216. He said they weren't that bad. I noticed a little machining but not much. ... a final note about the lower seal coming out. It may have been pushed out when reloading with grease the first time. Since there is a little slop (side to side) in the bobtach, I was watching inside seal while greasing, I went slow and could see it start to bulge out. I stopped there and will let it settle in for a couple of hours before regreasing. .... now really done, for now........ thanks for the advice here and I'll talk to you later. ... Ice
Tazza. thanks for the nylon info. Didn't realize it would wear that well. Wish I had the tooling it sounds like you have, and the where-with-all too. thanks. ... Ice
Glad it's all done, hopefully never has to be messed with again.
I have a bit of gear, but is it ever enough?
Just make darn sure you keep those lower pin bolts TIGHT, like check them twice a day for the first little while and periodically thereafter, also grease them twice a day with the lower tilt cyl bushings when operating in dirty conditions. I ran a shop at a bobcat rental store and noticed a huge reduction in lower buckett piviot pin and bushing problems when I added re torquing them to our regular check in proceduresGlad it's all done, hopefully never has to be messed with again.
I have a bit of gear, but is it ever enough?
Thanks for posting all of this as I'm in the middle of piecing my bobtach back together. One bolt came loose while plowing, the pin pushed into the bobtach and out of the lift arm completely. When the whole thing fell loose on one side it broke both bushings in the bobtach and mashed one side of the bushing bore. I found the bolt, pins, and all of the parts but man it's a mess. The pin still fits the taper in the lift arm so at least I don't need to have that reamed. The one bushing that I have intact is a loose fit back into the bobtach. Does anyone know the bore ID so I can figure if my bushing or bobtach is worn. Probably both I know.. I will get out a file and a hone to see how well I can clean the mashed side. There is one gouge that might need to be welded, and then bored back out. I imagine I could figure out some way of securely clamping it under a mill if needed.Just make darn sure you keep those lower pin bolts TIGHT, like check them twice a day for the first little while and periodically thereafter, also grease them twice a day with the lower tilt cyl bushings when operating in dirty conditions. I ran a shop at a bobcat rental store and noticed a huge reduction in lower buckett piviot pin and bushing problems when I added re torquing them to our regular check in procedures
Can you use a snap gauge at different places to work out if it's still round? i machined my bushings to suit the bosses. Sorry i can't give you factory wear limits....
Both bushings had a bit of a tick-toc where the boss they pressed into was worn. I figured that next go around I'd weld in new mount bosses onto the bobtach, and tig welded the bushings into the boss. I was able to get a small bead on the inside edge of the bushing, as well as the entire outside, and feel pretty confident that it will be strong. New seals and seal cups, and stacked some large washers on the side to eliminate the side to side play and I am back in business. SD
Thanks for posting this thread and all the pics etc. I was just able to do the exact thing by welding the pin to the bushing and pounding it out. Saved me a trip to a machine shop. I do still have the bushings on the cylinder to pound out though. Any ideas for that one? I tried pouding on an impact socket with a 4lb hammer that fits nicely on the cushing. It doesn't seem to budge. Trying to avoid that trip to find someone with a shop press.
I have run a few beads of weld inside bushings to get them to shrink slightly then bash out with a socket or air hammer.
