At some point in the near (1 year) future I hope to purchase a small track loader, Deere 350/450 or Cat 931 size machine. From reading in this and other forums I have learned what a good vs shot sprocket looks like. To measure across "x" number of pins after you have backed up the machine to stretch the track out and consult the chart to determine track wear and that a quick look at the idler position can reveal a rough estimate of wear (assuming the correct number of links) My questions are about idler wear and carrier wheel wear and what the photos are telling the prospective buyer. Attached are 2 photos, I would appreciate observations about what they are telling me. Thanks, Rick
Idler doesn't look bad at all, usually the center rib will wear narrower and the flanges will sort of wear down until the track links are sitting in a groove. The carrier is always the least of your worries, because it's cheap and easy to replace. That one is near the end of it's useful life, you can see the lip at about 10 O'clock is getting thin, when it starts to chunk out, slap another wheel on the shaft.
The complete carrier roller assembly, ready to bolt up to your machine is just over $100 at Off road. Like lantraxco said, not a big expense. With the uneven wear at the 10:00 position I would be checking the bearing in that roller to make sure it was free for an entire 360 degrees revolution.
If those components are on the same machine I have to wonder about track frame alignment. It's kind of hard to see on the idler but it looks like the chains are wearing against the center rib wearing it back toward the inside. That top roller has been flat spotted from being stuck.
The carrier roller's flat-spotted through having been seized at some point in time, the idler's not much better. What about some photos of the sprocket teeth and the external wear on the bushes..?
Ask and ye shall receive Rick
And 2 more Rick
Looks pretty good to me if not siezed up
Thank you to all for the lessons. Rick
Nige what are you seeing wrong with the idler? I'm still trying to master undercarriage
If that was my uc I would make sure that top roller bearing was good and then just run it.
Maybe it's the angle of the photo, but the idler tread where the links run appears to be "lipped up" towards the outside. They normally wear like that anyway. To prove that it would need a photo taken from right behind the idler instead of at an angle. If the lipping is more than about 1/16"-1/8" it's either replacement or rebuild of the tread by welding and re-bearing whichever is the owner's preference.
As Nige said, it might be the angle of the photo shot ? ….. but also the centre of the main idler is still nice and square ….. The carrier roller is a very common failure, excavators alike …… The roller is shot ! ….. not even worth checking if the bearing is good or not ….. BUT WHY ??? is the concern ….. I'm with the others here, it got seized and the rail dragged across for a long period of time, but not seeing the whole picture, as in: is it wore the same on the inside as out ??? ….. if not, then would in my books prove to have stopped turning, also if not ??? ... another common occurrence is rocks etc. get jammed up between the top frame and top of the pads causing either the main pedestal to bend, causing misalignment, or the main shaft of the idler got bent. As posted above they are cheap and in your purchase price can be adjusted. Another 'ol quick trick I was taught years ago, Was Grab, with both hands, either side of a Pad, anywhere there might be a bit of slack is easier, and Rock it back and forth, Left to Right as hard as you can !!! ….. If it seems to be excessive movement, then suspect the pins within the track rails to be worn out ….. by the looks of the pic showing the drive sprockets they are in excellent shape, Nice and square tips of the teeth, the gap or spacing where the pins contact are Not elongated, looks nice and uniformly round ... pending on total hrs of the machine, I would either suspect if it was a higher hour machine that those drive sprockets were replaced not long ago …… If you found the Movement as I mentioned before to be excessive and those sprockets to look like new then the rails have the appearance to be stretched or as the pins to be worn bad, will cause the track pitch to change and now wear out your drive sprockets really fast !!! …. If I get a chance later I will post some pics of what worn sprockets off of my Excavator look like …. they are worn out and I have to do a total undercarriage overhaul, Rails, Drive Sprockets, bottom rollers, and top rollers, front idler carrier rebuild the slides and rebuild the hyd track tensioners due to excessive stretch the tensioners exceded max travel the fr idler slopped back and forth breaking the main bolts that keep everything compressed ……. $$$$$$ ….. BUT the machine relatively a low hr (6500hrs) unit that had a lot of tracking time traveling …. just the cost of doing business !!! Hope these pointer help a bit too !!! …. Cheers … GK
What we really need is a sticky thread about undercarriage where people can post their "The Good, The Bad, and the Ugly" photos and then use it as a reference tool to help others learn about how to inspect undercarraige and what to look for.
Great idea Nige ! Who can make these a reality ?
Ask a Moderator I suppose ...... one problem would be where to put it because there are a number of different parts of HEF that deal with tracked machines.