Cat Challenger 95E 6KS00900. Had a bit of a problem last week, bearings in one of the front idlers failed. By the time I figured out what was making noises, the hub and spindle assembly had been wiped out. Sidenote: duo-cone seals will take a lot of movement before they fail. Anyway, question for whomever can answer. Installed the new cups in the new hub, installed each half of the new seal (went well, everything looked pretty much spot-on), and proceeded to install the hub onto the spindle. Since it was all new parts, not on the tractor, we were able to just lower the hub vertically directly onto the spindle, keeping everything nice and square. It all seemed to slip together perfectly, outside cone slid right into place with no movement of the hub. What I'm concerned about is when I inspected the seal, it appears to be slightly out of alignment. Not sure what to make of it, wondering if I'm going to have to lift the hub back off and reposition the seal. I don't really want to, lol. Edit: When I say the seal is slightly out of alignment, it means one side seems to have pushed a little further into the hub than the other.
How do you mean "out of alignment".? Got photos.? Duo-Cone seal are normally installed using a plastic height gauge to get the steel face ring absolutely square with respect to the bore although you can also do it with a vernier guage or even a 6" steel rule.
Thanks for seeing this Nige. I edited my post to say that it appears one side is pushed a little further down than the other. I'm not sure how that could happen, we lowered the hub perfectly square on to the spindle.
How did you install each half of the Duo-Cone into the housing.? I hope you didn't use lubricant on the ramps..........
Cleaned everything well with isopropyl alcohol before I installed the seals, just like the directions say. I didn't have the fancy tool, but a couple of guys I know suggested that a piece of 2x10 will work just fine. I placed the paper that the seal was wrapped in between the block and the seal when I pushed it in. Both halves looked just like the diagram before we set the hub on, the large o-ring was just slightly higher than the edge.
Pushing it into place requires a steady application of pressure rather than hitting it, which can crack the steel ring. OK, just wanted to make sure that the whole shooting match wasn't sliding up & down the ramp instead of the O-Ring rolling as it should do. Did you measure the height of the ring above the casting at four points around the circumference to make sure it was in square.? Only way to tell if the misalignment might be significant is a photo if you have one.
I'll take one this morning when we get to the shop. I didn't measure before we set the hub on, but only because it looked pretty much perfect. So, is a small amount of deflection ok? It's enough that you can see it, so I'm guessing .050-.075" off? I'm not sure where we possibly could have went wrong here. Setting it down vertically should have been the best you could possibly get. Two guys trying to handle that heavy hub sliding it on with the spindle on the tractor just seemed like a recipe for failure?
You might not be able to see the deflection in a photo....
Usual way is to have the stub axle off the machine and oriented vertically and then lower the hub over it using a hoist. If you did it that way then it ought to be right. There is a certain amount of tolerance on the height of the ring after installing the Duo-Cone. From memory it's 1mm or 40 thousandths. Question: Are the wheel bearings adjusted already..?
The rubber ring sits in a hollow land. Most of the alignment problems I've had with those seals is that the land isn't perfectly cleaned out. Dirt will fill the hollow part and then the ring won't sit square. If they are clean, you can use the flat side of a standard screwdriver to push the ring into the land. You can actually feel when it slides into the seat.
Not yet, trying to locate a socket, looks like we'll be building one. You suppose the hub will draw down some more and the seal will straighten out?
All new parts, John.
I don't know about Challengers but all the seals I've put in for idlers on dozers and excavators, the rubber rings will sit just below the bore edge that they seat in. I've never heard of anyone being successful in just using a flat surface against the metal and pushing the ring and seal in together. The special tool wraps around the metal ring but actually pushes against the rubber ring to install in the bore.
So, what would you consider "unsuccessful"? Both halves slipped in as good as I ever could have expected, and the rubber ring was just slightly above the bore edge, as square as it could possibly be. The new seal came with an illustration, and the way my seal was installed perfectly matched the illustration.
So, running things over in my head, once I get the bearing preload set, rolling that hub around carefully should allow that seal to align itself? I realize I'm probably being overly cautious, but I don't want to have to redo this.
As John rightly says to install "by the book" you have to push on the O-Ring to install the seal, not the metal ring. That's the purpose of the installer tool. Keep spinning it plenty at the same time as pulling up the wheel bearings and you shouldn't be far off. If there was no measurable height difference around the metal ring when the two halves were installed in the hub and on the stub axle it sounds like it went in pretty much right. EDIT: Installation instructions attached. I was right abvout the 1mm tolerance (page 5).
Has the bore been checked? We commonly weld and re size them
The ring will not slide down when pressed against. It will roll instead, which causes it to push tighter against the ring and the bore. You can do what you want. Just keep in mind how far you have to go if it doesn't seal. It most likely will be fine, for awhile.
The thing I have a habit of, once all parts are cleaned or replaced as necessary, is to fit the hub with bearings onto the drive assembly according to spec with no cone seals installed thereby allowing you to check for bearing fitment is proper, with the floating seals installed this is much harder to determine. With no floating seals installed you can get a much better feel of the load on the bearings and things are able to rotate properly. As for the floating seals, yeah, most of us hay seed wrench benders don't have the fancy install tool that pushes the toric ring into the ramp housing. My redneck trick is to find something that will fill the gap between the toric ring and the flange of the steel ring. Might be a piece of insulated wire, like 12 ga primary wire, might be a piece of the coiled housing of a choke control cable, but you need something that perfectly fits that gap. Wrap it around the gap between the toric ring and the flange of the steel ring, hold it in place by wrapping electrical tape around it. Now you can place the seal on the ramp housing and push against the face of the steel ring and it will force the toric ring into the ramp housing and not allow the toric ring to ride up the ramp of the seal. And I must confess, pushing them in dry by hand is a challenge. I don't use oil lube, but I do spray the ramp housing and the toric ring with spray silicone lubricant and let it dry, that does help things slide together a bit better by hand.
Thanks for all the replies. After we loaded the assembly onto the back of the service truck, I inspected the seal again, and realized that the toric rings had not slid down evenly when we installed the hub. Since we had it up high, easy to work on, we hoisted the hub back up, removed, cleaned, and reinstalled the seals, making sure they were as true as we could get them. I was able to watch the seal halves come together as we lowered the hub back down and everything settled in the way it should. I'm not sure what went on the first time, maybe we didn't lower the hub down as straight as we thought? Anyway, it's back on the tractor and I just got home after working it for 9 hours. Thanks again you guys for the input.
As well as making sure the seal surface is level, it's vital that the toric isn't twisted. There will be a faint mould parting line on the rubber which you can use as a reference.