cat 304 track roller

[jbernielh]

so I noticed a little puddle of oil on my rubber track the other day.. had a feel and a sniff.. definitely oil, and not a hypoid gear oil, no stink.. it was directly under my rear track roller.. I immediately thought my final drive was leaking but after looking it over closely everything was completely dry including all the hoses going up to the swing valve.. looking closer the roller was damp and there was a drip of oil on it..

so the big question is... are the track rollers oil filled? I would have thought they would just have sealed bearings.. there's no doubt it's oil, and it's situated specifically on the one roller, and after it's sat for a couple days there's a spot of oil about the size of a quarter on the track..

Bernie

 

[Nige]

Yes those rollers are oil-filled with a non-EP oil, so no gear oil smell. No bearings in them but bushes (2 of Item 5A below)
They are sealed by 2 steel face seals, one on each end. I can't find any disassembly/assembly instructions so can't be of any help regarding exactly how much oil should be in them. The parts 1 thru 5A shown in the illustration below are all available individually which gives the impression that a roller could be rebuilt, however I'd price up a complete roller assembly first decide whether or not it makes economic sense to even try to rebuild it.

 

[jbernielh]

thanks much for that information Nige.. I suspect a replacement roller will be the way to go.. my machine has just over 2K hours on it and have had to replace both of the top idler rollers.. a lot of weight on a single roller and its only supported on one end.. no wonder they lose the inner bearing.. those ones are dry, no oil.. I looked into rebuilding those, and didn't get very far before realizing I could buy a new one for half the price of rebuilding.. I suspect the track roller will be the same.. I'm going to check with finning in the morning.. the guys there are pretty good.. they will usually match aftermarket pricing.. hopefully it's not to pricey..

Bernie

 

[Nige]

There's a big difference. The carrier rollers are non-rebuildable - there are no separate repair parts (via Cat anyway) quoted for them.
The track rollers on the other hand can be rebuilt. Why not try pulling yours apart and see if you can spot what the problem is. The fact that there is oil in it (as evidenced by the fact that it's still leaking out at this time) you might be lucky and find it only needs the Duo-cone face seals replacing which would be much cheaper than a new roller. What do you have to lose by pulling it apart if it's already goofed ..?

 

[jbernielh]

true enough Nige..

I bought a new roller for 150 bucks.. I am going to dismantle the one I took off and have a look at condition and parts availability and pricing.. then I'll make a decision as to whether or not I'll rebuild it as a serviceable spare..
not sure where you looked re parts for the carrier roller but my PC shows all the pieces, bearings, seals etc.. mine is a 2008 304C CR

Bernie

 

[Nige]

You never gave a Serial Number and titled the thread "304", so that's where I looked, not 304C...........
When I look at 304C you are correct, the carrier rollers are theoretically rebuildable.
For good parts information it's always advisable to give a machine Serial Number, or at the very least the S/N prefix. Even for 304C CR there are 3 prefix options, ENW, FPK, & STB.
Here is your track roller. As you can see it's slightly different and also the bushes are not available separately like in the earlier machines. Wear on the shaft or on the roller bushings would probably be enough to render a roller uneconomical to rebuild.

 

[jbernielh]

I got a chance to pull the removed roller apart today.. actually in pretty good shape, but then it's only got 2200 hrs on it.. item 5 on your parts breakdown are actually a rubbing seal system with 4 large orings.. I'm going to see what Finning wants for the seals and if it's ridiculous I'll just replace the orings.. it will be a good spare to keep on hand.. Nige you have any idea exactly what oil is used?
Bernie

 

[Nige]

The seals are called Duo-Cone seals (steel face seals in other words). According to the Parts Manual for FPK-prefix 304C CR machine the seal assembly is a 158-4712 - check to make sure that is correct for youtr machine. The O-rings for the seal are not listed separately. Normally the seals leak because the steel sealing face gets badly scored with all the dirt, complete replacement is the only answer.

If your metal faces are in good shape you could consider just replacing the O-Rings. Ask Finning if they sell 279-9085 O-Ring separately. That is the O-Ring for the 158-4712 Seal Assembly. Don't be surprised if they tell you it's not available, in that case you'll have to bite the bullet and buy the complete seal aseembly. Oh, and BTW the seal needs special tooling to install it .......... or it will leak ...........

Oil in the roller will be an SAE50 TO-4 powertrain oil.