Carrier roller tear down (6K9879)

[SubMech]

Looking for some tips on how to best disassemble a top roller off my 215B (9YB03340). It is off the machine on the bench.
For example, do I press the shaft out of the hub from the cover side or press the shaft out of the mount bracket?
Seal housing seems to have dowels and a snap ring holding it to the mount.

 

[56wrench]

looks like pull, push, or hammer the whole assy out of the mount. then remove the seal components from the backside of the roller. then press the shaft out of the bearing( cover side) it should have a duo-cone seal assy but I may be wrong. if the bearings are good, reuse them. just adjust to proper preload. after seal installation and reassembly make sure the whole thing is seated in the mount correctly to preload the toric rubber rings of the duo-cone seal or it will leak. also the seal mating surfaces have to be square during assembly. ( there is a handy little plastic gauge and wire hook that used to come with CAT seals. last but not least, the mating surfaces of the steel seal rings and the toric rings must be clean and dry during assembly or it will leak. hope this helps--it may be a little bit vague. I can give more detail if you need

 

[SubMech]

I found a cut away drawing that shows you are correct on the seals. Looks like the preload on the seals is determined by how far you press the parts together on assembly. Need to figure out the drawing before I start whacking at it with the hammer.
Thanks to 56wrench, I do appreciate the input.

 

[Mark250]

item 2 is a retaining ring that holds the seal retainer make sure you remove that first otherwise as above

 

[56wrench]

I forgot about the snap-ring. my memory ain't as good as it used to be lol. cat has used this style of carrier roller going back 50 years (give or take) on tracked machines

 

[DMiller]

Dowel pins are locater pins for the shaft to the support to keep the seal package from rotating should it bind up. Most likely locked in with corrosion. Bearing retention cap has been removed, have to remove the roller and bearings from the shaft, preload is performed on assembly as bearings are reloaded.

 

[SubMech]

Managed to remove the roller from the bracket. Required some careful use of steel wedges to move the dowels out of the seal retainer while advancing the shaft via a brass drift.
Shaft dials in a little bent but only .007 thou. Not sure if this would be enough to cause the uneven wear or just the result of some bigger issue.
If you look closely at the bracket you can see the track ran on the top of it long enough to remove 1/4 inch of material which means the track was running to the inside. Must have changed the roller at some point. Does it make any sense to rotate rollers like tires on a car? Even out the wear?
Not really surprised, the machine is a 1987 vintage, that's like 100 in dog years.

 

[Bluox]

That wear pattern means some one had their head up their butt and ran the tracks half off the roller quite some time. Are the tracks well worn ? I would have put them back on and run that roller.
Bob

 

[SubMech]

Makes more sense than the slight bend. Track ran on the inside and wore away the inner roller flange and part of the bracket to the point that the inner flange can no longer retain it and now allows it to throw the track off the roller to the outside.
And yes, the tracks are fairly worn with the pads showing the most wear.
As I dig deeper into this machine I will have many more " learning opportunities" I am sure.
Thank you for the insight Bluox.

 

[Bluox]

If it throws the track now might as well replace it ,check with Cat for their cheaper undercarriage roller and replace the whole roller.
Bob

 

[DMiller]

Bent should have slight effect on surface wear, doubt it would affect slipped rail at .007. Snakey rails could be a problem if had SALT and the seals had gone where internal pin/bushing wear caused a roll off. Should check alignment of idlers also, may be running offline.

 

[Vetech63]

I haven't tore down a roller in 20+ years. I couldn't rebuild them cheaper than I could just replace them and be done with it.