Rebuild track idler HELP? (Kubota KX41-3v mini-excavator)

[Sodo]

Bearing went out on my front track idler. I thought the sound was just rocks going thru the track, then noticed the font of the track wobbling. Checked if the hub was warm, and it was....almost HOT. Also had suspected one side drive motor getting weak, pretty sure that the idler held that side back. 1360hrs.

I found a new replacement for $275 delivered. But can't find anything on the web about replacing the bearings.

So are the track idlers NOT rebuildable?

 

[Sodo]

Got this KX41-3v parts diagram from the dealer.
Looks like it's rebuildable.
Will tear into it.

050 BUSH looks like the "bearing".

 

[BukitCase]

I"d say you nailed it - bushings are almost ALWAYS used in high stress applications like that, ball or needle bearings are limited to the tangent point between needle and race, times the # of needles - bushings are MUCH closer to 100% than that, usually up around 70-80% contact instead of maybe 10-20% -

Also, somehow I doubt those particular parts are gonna run a few THOUSAND rpm ...Steve

 

[Sodo]

I wonder what kind of lube it uses. Or dry? No serviceable parts, there is no grease fitting, simply is a "2,000 hour" wear part. It has 1363 hours on it, total failure, 3/8" of slop in the wheel bore to axle. The wobbling wheel/roller destroyed every surface, even the seal bores and the yoke support arms.

Of course I'm thinking I can get a new one and put a grease fitting on it. I ordered the new idler parts, I suppose they will arrive in a week or two. Very easy install.

Anyway I "powered on", invoking my dear old Dad. Pics below. Word of warning, if you're squeamish, or just ate your lunch, turn away from the computer screen NOW! Don't say I didn't warn ya!

Heres the idler wheel unit. It simply slides out of it's slot, held in by track tension.

I can't even tell what kind of bearing was in there. The hole is 3/4" bigger than the shaft.

OK now get this. My iron pile is only about 6 years old, and for the 1st 3 years was basically NOTHING when I had curtailed my desires to drag stuff home, and quit for awhile. So how in the HECK do I have two pipes in stock that make up this slop almost perfectly? GOOD CLEAN LIVING that's how !!! And bringing a little stuff home, good materials only. I highly recommend it. But be careful what you drag home, everything is a project.

Anyway the bigger pipe had to be sanded down a little and it pressed in. Note the predrilled grease holes. The little pipe has about 1/16" slop on the axle, and about 1/16" slop to the bigger pipe.

I had to chisel the seam out of the bigger pipe. I ground a chisel round first.

Ground the thrust sides flat.

Drilled a grease hole.

Put it all together with one thrust washer on the other side. But it still had 1/8" slop which couldn't be dealt with by adding a washer because of a nested snap ring. Not assemble-able if washers take up ALL of the slop. So I made a washer split in two.

Welded the washer halves together and now I'm out in the woods diggin again!

Thanks Dad!

However if my dear old Dad knew I ordered the new parts (and will toss this repair before running it out) he would not be happy ---- but he doesn't have to know that.

 

[downsizingnow48]

That's a great shade tree fix.

 

[Sodo]

Got my new idler, next time the track is off I'll replace it. I'm interested to see how the shadetree bearing fared.



This, according to the maintenance schedule, is simply a "2,000hr replacement item".

I'm wondering if I oughtta drill & add a grease fitting -or- if its supposed to run dry. It has a rubber seal - I wonder if theres grease in there now? Prob no passage for grease to pump out, but as it wears loose there will be. Who knows about these things?

 

[Rattlerjake]

Got my new idler, next time the track is off I'll replace it. I'm interested to see how the shadetree bearing fared.

View attachment 483927

This, according to the maintenance schedule, is simply a "2,000hr replacement item".

I'm wondering if I oughtta drill & add a grease fitting -or- if its supposed to run dry. It has a rubber seal - I wonder if theres grease in there now? Prob no passage for grease to pump out, but as it wears loose there will be. Who knows about these things?

So, three years later how did this repair hold up or did you just swap it out for the new part? Where did you order that tension wheel from? I have a KX41 needing the same fix.

 

[Sodo]

So, three years later how did this repair hold up or did you just swap it out for the new part? Where did you order that tension wheel from? I have a KX41 needing the same fix.

I didn't run it out, only dug a few days on it.
Which is not really normal for me.
I like to know how long my shadetree repairs might run, and especially if the replacement is in-hand, why not?
In this case...... because whenever a track comes off, it's kind of a hassle, and work stops in its tracks .
so I decided to install the new one.

Cost Sept 2016 was $230 + $45 shipping.

RB237-213�9 Kubota KX41-3V Idler
1-800-719-4160
idler: RB237-21309

Incidentally getting a track back on,
I've used a crowbar, and loosen the grease fitting
but not actually take it all the way OUT, just relieve some pressure.
some grease comes out,cuz theres a relief slot in the threads.
Operate the track motor very slowly.
KX41 is small enough you can operate the drive lever while
holding a crowbar to guide/stretch the track back on.
I think I must have done this at the sprocket, but could have done it at the idler. Sorry I can't remember.

And wish I had a vid, but I only have two hands and this is a 3 or 4 hand job as it is.
It would be far better to have a 2nd person helping.
And somewhat dangerous too, think about where that bar could go.

More tips.
Here's track fully off.
Note using the blade
-to push a socket extension
-to push the idler back in (and grease out).

If the track is ON the roller, this is a little easier 'cuz it doesn't 'roll.
You can cut a longer stick in the woods and push directly on the idler slider too.

 

[Seven Gables]

Nice work on your temporary fix , saving those old pieces and parts sooner or later pays off. Your question about lube for the idler bushings , I'm quite certain they use oil not grease. If you look at your parts diagram #030 is a Allen head plug , I also spotted it on your original idler support arms. That is your oil fill plug I believe. I did not see it on your aftermarket replacement . My Volvo excavator has one also except it's located on the wheel itself. That's where the factory fills them . If and when the seals go and I spot it in time I would pump corn head grease or the like in that plug hole to see how much time that would buy me. B