While I (profess to) have a great deal of knowledge in many areas, I am admittedly lacking in some areas of excavator tracks. I lack experience/knowledge in what -NOT to DO- if to keep a track on. Cleaning mud/rocks and track adjustment I understand. Sometimes as I use my 312B I hear a loud POP from the drive end while moving back or forth. I assume this is the drive teeth popping on the track. Am I doing something wrong? What should I avoid doing –or- how are tracks commonly thrown? Do they usually come off the drive end or the idler end? . . .Why?
A lot of times the loud pop is just a good sized rock/other that got between the track and just cleared itself. Proper tension is key to not only keeping a track in place but making sure you get the most life out of it A lot of why a track comes off will be because of the shape it is in... are they at the end of their life??? are the sprockets worn down pretty good and pointy??? if the idlers are worn good just some good packing soil and a little bit of angle on the pads and you will drive right out of the track.
Good day Cat May I suggest it would be better to focus on keeping the track on than loosing the track, the "Pop" you describe could be a result of the recoil spring returning to the normal state after some stone has become trapped in the drive sprocket, chain loss is normally associated with wear and prevailing ground conditions, track pads can also have some influence. Please see attached which may help. Kind regards Uffex
Sorry omitted information
Thank you Ronsii. The sprockets are 'a guess' about 50 % and not 'pointy'. The track appears to be bout the same and in good shape. I keep on top of worn things if I know what to look for. I replaced the TOP rollers because they were getting fairly hot when traveling. I replaced a couple of the bottom ones for the same reason. THANK YOU uffex! You always seem to have and provide EXCELLENT information and documentation. You appear to be quite knowledgeable with 'problems'. The "prevailing ground conditions" is one thing I was wondering about. I assume there some which are more PRONE to losing a track, perhaps ANGLES (let/right) of the track when traveling. I am VERY CAREFUL when rocks as I figure they can pop off a track, but uneven sloped ground . . .?
Does your machine have good guides behind the idlers on the bottom side? I had a 9050B Case that loved to throw tracks on side slopes until I rebuilt the guides front and rear and built some heavy duty center guides too. Also, in rough stuff it seemed to help running sprockets forward to keep the rails tight on the idlers.
When it comes to a machine throwing a track, track chain wear will be the big factor. If there is significant side-to-side movement ("snaking") of the tracks while the machine is moving from worn pins and bushings, then it's more likely to jump the bottom roller flanges and pop off the idler. This will most likely happen during hard-pivot turns, and deep mud or snow will multiply the chances of it happening. With an excavator with worn tracks, you can lift the one track and jog the chain forward and backwards to straighten the tracks out when you are working in a tight area that requires hard pivots.
Matter of fact I replaced them on one side as they were hot after traveling. A good tip. They seem to wear a lot more than the others. I think I'll replace them on the other side. "Also, in rough stuff it seemed to help running sprockets forward to keep the rails tight on the idlers." When working in a steep area like a creek crossing is there any difference 'backing in' or going in 'forward'?
Another good tip. Thanks. That is the type of area I often get into, having to maneuver in a sloped small area. I rarely do anything on 'level ground'. One place I try to be careful is traveling across a steep narrow ditch. Is there a good way to do this?
When crossing a ditch, try to avoid a scenario where the track will "sag" away from the track frame, as the bottom rollers are what help maintain the alignment of the track; once you lose that alignment, you enter the conditions where the track will jump off. This is why track tension and drive sprocket orientation are so important.
So is it best if I cross at a slight angle instead of straight across? (FWIW My Cat 312 has wide pads) I realize these are pretty 'dumb questions' for anyone experienced but I am 'self taught' (like with most things I do) and sometimes start thinking (that's a bad sign) if I can improve what I am doing to help prevent having to 'undo' what I did wrong out of ignorance. Excavators are just TOO EXPENSIVE to fix if you screw up.
Trying to go at an angle is asking for trouble, as you will have stability issues and get into worse trouble than a thrown track. As I said, track tension and drive sprocket orientation will help you out the most in that scenario. It will be if the track tension is too loose where your tracks will sag and become misaligned.
Oops, I should have clarified the type of guide I was talking about. Those are steel plates coming down from the track frame to guide the rail/chain into the idler or sprocket. I don't have a pic or I would post it up.
I believe you are referring to rock guards. They are immensely helpful when working in uneven terrain.
Thanks for the clarification. That is 'one thing' I have not looked at and should.