I'm slowly working through the pins and bushings on my 1845c. I've got the lower arms and bucket cylinder pins/bushings done and now i'm on to the triangular plates on the boom. The plates themselves don't have bushings and are wallowed about .06. The upper arm that is pinned to the triangular plate doesn't have a bushing either. Only the cylinder and the main loader arm has inner bushings. Over time the the plate holes have wallowed. I'm considering using either a bridge reamer or an adjustable reamer to bore out to 1-1/6" which is 1/16" oversize and very close to what the maximum oval hole dimension is at (1.060). I'd need to have a machine shop make new inner bushings with the larger 1.0625 ID to match oversize pins. I have only a little experience with an adjustable reamer and none with a bridge reamer. Will these take care of an out of round hole? Is one preferable over the other? I'd do it by hand, but would need to do 14 holes (4 plates with 3 holes each and 2 in the upper arms). I don't believe alignment is a major concern here so line boring isn't necessary. I feel like I can make my own oversize pins...just buy 1-1/6" O1 tool steel from McMaster, weld a washer on the end, heat it red hot and quench in oil. Anything I'm missing?
.005" interference with only a 1 5/8 bore. That bushing is gonna probably crack or the bell crank itself. With a bore that small I would not exceed. 0015" more like .00125 . You just want to hold the bushing in place, it's not a rotating wear point. Your machine shop has a formula that dictates bushing to bore fit . Good luck
To me ,removing material from original piece to make room for a bushing would weaken it ,especially since it has a bolt hole going through it
To clarify, I'm not suggesting boring the triangular pieces to receive bushings. There is not enough material to bore that big. I'd just bore them to 1.0625 (1-1/6"). They are currently wallowed to 1.060" at the widest point. Assuming I can successfully bore them, I would need slightly oversize pins. The boom that is in between the 2 triangular plates have the bushings, which would need to be remade to accommodate the oversize pins. My question is about what type of reamer (or anything else) to bore those egg shaped holes from 1.030 (at narrow point) 1.060 (at wide point) to a round 1.065" hole.
If these aren't perfectly parallel they will make for a lot of strain. How did they get worn that bad? There should be no friction where they are held by a bolt. I'd say a boring bar, two bearings, a drive machine. bring them perfectly round without enlarging more than absolutely necessary, then bigger pin. I'm surprised there is no bushing.
I think some welders could Weld up the inside and rebore to original dimensions
Reamers simply wont work they are going to want to follow the hole and probably break the blades on a adjustable reamer definitely a job for a machine shop I understand wanting to do it yourself but just done see how it could work 4140 would be plenty good for the pins no need to weld you need to drill for bolts tool steel could snap if its too hard and not tempered back properly
Seems like you could remove both triangles attach/clamp together and bore in a mill. And maybe rebush the bore to original.
I had a 1845C and the pins, bores on the triangular pieces were also worn out. My observation was that there are lots of pins and they are too small diameter for that size machine. What 6800 pound skid steers have 1" pins? Maybe the previous owner didn't grease them enough. To clarify, I think the OP means 1 1/16" not 1 1/6"
Can't weld those plates...they are cast. Not sure how the holes got worn but when the inner bushing wore, then the pins can rock/twist. Yes, I meant 1-1/16" in my earlier post.
Cast iron or cast steel?
Ductile iron includes magnesium to give it ductility. Ordinary cast iron is tough to weld due to porosity, contaminates, and a severe lack of ductility. Ductile is hard to weld because of the different behavior of iron & magnesium, you don't weld in the same way. I'm not convinced those holes are ovaled that much. I feel you have the wrong sized pin. Measure the smallest dimension of the layers each pin passes. I wonder if a pin sized to match the bores would tighten it up.
Yes it's ductile iron. The egg shaped holes are 1.030 (at narrow point) 1.060 (at wide point). The current pin is 1.029" and is round a the widest point where it contacts these triangular plates. I doubt it's the wrong pin. It's hard to say how much that pin is worn, but again it's not oval and I'm hesitant to go buy new pins at $49 a pop if I'm going to end up with oversize pins anyway. I don't have much reference as to what is "bad". But I can tell you it's pretty tricky grading with the machine because the tip of bucket acts like it's in float mode as it rises and dives with the slop in the linkage. It doesn't have to be "like new" but it does need to be better. I've only done 2 of the 8 pins so far however. Maybe if I just do the others it will take up enough slop to be good enough....
Are all four plates worn that badly ? Have you removed the pins and examined the pin bores in both ends of the arms ? I would think that those bores would not be terribly expensive to repair, because they can be easily removed and taken to a machine shop.
I have not removed them. But all the outer bores appear to be worn about the same. They would be pretty easy to remove and bring in to a shop though...which is the way I am leaning.
Most equipment pin include three bearing surfaces where a pin contacts. Not unusual for the bores where the pin doesn't rotate to not be bushed. I'm surprised to see this much wear in those holes. I believe your best fix is line boring. You haven't said whether the point where it should rotate against the pin is bushed.
you don't need line boring for this. You're fine drilling them to 1 1/16" and putting in an oversized pin without a bushing. You could do it with a drill press, milling machine, hone, pin and grinding compound, maybe a few other methods. I don't have much experience with reamers, but an adjustable reamer would not be my first choice. I agree with Jonas, you'd break the reamer. I do think you can do this on your own though, it's a skid steer, not a mining shovel that's going to see 10,000 hours to it's next full rebuild.
Well, if that's the plan, get a hole saw, lube & take your time.
Two of the three pins are bushed in the middle of the plates where the pin rotates. The third pin is not.
The parts manual shows a bushing in the in the loader frame. #11. All the holes use the same size pin. Can the worn holes be bored to use that same bushing ?
Unfortunately, no. There isn't enough material on those bosses to bore it out that much. I think if I can bore it to 1-1/16" I'll be good for the life of the machine. Or as long as I will have it with mainly homeowner use and occasional contractor work.