Good Morning Everyone, Many here have help me in the past with my old PC 60-6. I just cant bring myself to replace it. After much work I was able to eek the summer out of it. Few hiccups along the way. I would like to send it back this summer to the same island job and definately need to do some more work. It definately needs chains. Walks off them all the time. I have found replacements no problem at the Cat dealer. Once I pull it in the shop and tear it apart. How do I determine what else it needs? The sprockets look ok. Not pointed at the ends. How do I determine if the top and bottom rollers need to be replaced? The same with the idler sprocket? Will I need to torch all the pad bolts off or do they ususally impact out? Do most people re install the pads? Any bit of help is greatly appreciated. I want to order parts soon to hopefully avoid covid delays.
Good day A video you may find helpful. Kind regards Uffex
there are specs for sprockets, rollers, and chain so you can measure everything and see how worn these items are. You could take a link out of the chains if there not worn too bad. Confirm you track tensioner is holding your tracks tight. Youll need a pin press and a torch and some new pad bolts. its easier to cut the pad bolts off then to try and save them.
If you install new chains, you're defeating the purpose if you don't install new sprockets. They are a matched set. Everything can be measured to determine if it should be replaced. Idlers are usually good for more than one set of rails. Pad bolts should be replaced as well but some people reuse them. Torque on them is very important. You're machine is relatively small. Be glad it's not D6 size or larger.
Sprockets and chains usually wear at about the same rate so a chain can be worn and usually the sprockets are about the same. Having said that, they are not a matched set. It was common in the times when your model of machine was new and it was sold into north America for the tracks to be replaced and all the rest of the undercarriage to be original. So what you see now is a lot of mis-matched components. The other issue on the mini's is that they don't wear out in the same ways or at the same rates as larger machines. The issue of measurements is also problematic on mini excavators. A measurement is only good if you have a standard to compare it with. Sprockets, particularly on mini Komatsu excavators don't have percentage worn specifications that I have seen that you can look up. Komatsu doesn't put out an undercarriage manual so the rest of the specs have to come out of each individual service manual per each machine. Post some photos of your machine and the undercarriage components and I can give you some guidelines. Both sprockets showing the teeth, the position of the front idlers in the track frames, the bottom rollers showing the flanges as they are over the track pin bosses. From there I can give a good idea of how worn out those components are. You might consider looking at my video that covers excavator undercarriages.
Good grief man! Matched set as in new sprockets match the pitch of the new chain.
Good day I guess B. Builder is looking for wear data applicable to the Komatsu PC60-6 with steel tracks, my files only have PC50 I am not sure if that is the same. Anyone on the forum have a manual ? Kind regards Uffex
I just removed my worthless comment.
Minis are not as fussy as larger units, if you can source new sprockets reasonably get them in and don't look back. If they're unobtanium or priced like platinum and your old ones look decent to your eye, they'll wear in to match the new track. Might be a little extra wear on the bushings but almost always it the internal pin/bushing joint that gets sloppy. Do not reuse the pad bolts, they're ridiculously cheap especially in and aftermarket brand and the originals will be nasty and stretched. On small machines I hit them with the impact set to tighten, much easier to deal with if you can snap them off. Be sure to clean the back of the pads and clean the pain off the new chains where the pad sits. JMHO, YMMV
Hello Everyone. First I must apoligize for taking so long to reply. For some reason I dont get a notification if someone comments. Second, thank you very much for all your great advice. I really appreciate that you all help me with my repairs. I could not do it without. Per John C.'s comment I will wait for a short stretch of warmer weather. -20 today and I will fire up the old girl and bring it in the shop to thaw out. I will take some pictures of the tracks and sprockets as well. The chains are for sure worn out. The Pads have alot of side to side movement. I will update as soon as I can get this done. Thank you
Good Morning, Sorry to dredge open my old post but the weather has finally gotten better and I fired up the old PC60-6. I have ordered the chains and nuts and bolts for replacement. I am going to take pictures of the sprockets and rollers today and post them to see if anyone has thoughts on wheter I should be ordering sprockets, idlers, and top and bottom rollers too. Being its an older machine and isnt working all day everyday. I do want to keep it in decent working condition.
Hello, So I blew the dirt out and took some photos of undercarriage. Anyone who wants to share there opionion on what I should replace I would welcome it. Not sure if I can attach them all or in a few posts.
More pictures
Last bunch
Let me know if any other pictures would help.
In this throw away society I ran track gear to 100% destruction. All the rollers and idler don't require replacing.The track rails look OK. If it was mine the most i'd do is remove a chain link. There could still be over a 1000 hours left in what you have IMHO.
If a roller is frozen, rattling or otherwise broken replace it, other than that it all looks mid life decent, just run it.
Hi Guys. Thanks for the advice. I will leave the rollers then for another time. I need to replace the chains. The pins in them are really worn and the pads rock badly and they wont stay on the bottom rollers. Maybe I will just replace the chains with nuts and bolts and see how it works. When you say remove a link...do you mean you can shorten the tracks if the idler runs out of adjustment? If you do mean that, I didnt know that was even an option.
Yep thats zackary what I meant. The last machine I did was a forestry mulcher and got another 1000 hours before replacing any components. Unlike an excavator that machine was moving all the time.
He was talking about slop in the links, pins and bushings, not loose bolts or pads. Need new chains or a pin and bushing kit installed. Depends on how close to a track press you are and the availability.
Posted on wrong post.
Good Morning. Thank you very much. Yes. I dont think the pads are loose on the chains themselves. As Traxco noted I think the pins are worn and the chains move around alot and pop off the bottom rollers with the slighest movement. I have ordered new chains and track bolts. Any tips on make the job easier? Is it easier to take all the pads off while still on machine, replace the chain and re-install the pads with the new chain installed?
Yes
When you say pop off the bottom rollers do you mean it just walks off of those but the track stays on the idler and sprocket? If that's the case I would say what you really need is track guides also known as rock guards to keep the chain on the bottom rollers. They don't need to be full length, even just a section in the center helps immensely if it doesn't have anything at all. From the pics it looks to me like everything else is fine. If the tracks stay tight there isn't really any reason to mess with removing links. Once the idler moves over half the distance of a link you can remove one if needed, it is pretty common. The first sign that that is needed is usually idler frame starts poking past the track frame and you can't keep the track tight. As far as guides I don't have any great ideas on how to get them. I don't know if they were ever available on those but most likely it would be easiest to fabricate them if you have the capability. The new chains will solve the problem as well, if you could install some kind of guide you will get a lot better life out of them in my opinion.
Those chains show little wear on the links but it does appear by looking at the sides of the track chain that the track pins are working in the links. When the links are stretched, the front idler support blocks are usually poking out the ends of the track frames. Yours don't looked stretches at all. I'm guessing that someone may have already pulled a link out of each track. Have you had the machine since new or bought it used? This is a small machine and it is pretty common to put little wear on the link rails but put a lot of internal wear on the bushings and pins. How wide of pads do you have on this machine.
Hi Guys, I bought this machine used. But many years ago. The track pads are 24 inches wide. I hope someone didnt cut a link out because when I ordered the new chains they asked me how many pads the machine had which is 37. Does anyone know if this is the number the machine came with? To answer your question it doesnt come off the sproket or idler. Is just pops off the lower rollers and then track will be a little bowed out where it sits on the ground. Lifting the machine up with the arm on the side it happens pops it right back it. Also I can rock the pads back and forth quite a bit with my hand.
I will ask the place where I orderd the chains ( Cat dealer) if they have chain guides or rock guards for this machine also.
Just looked through the parts book and it looks like 74 pads total. So thats good.
Tracks popping out the side isn't any big deal and if you take notice it will happen most when the sprocket is in the forward position. Tramming any long distance run the machine with the idlers at the front and when digging do it over the sprockets To be very honest I think you are making mountains out of ant hills and are blowing coin on something that doesn't need doing. Try running the tracks a little tighter. Hope this helps.
Good Morning, The chains are on the way so will replace those. The machine has a blade so I dig over that when possible. Makes it more stable with the small machine. I assume its easier to take all the pads off while still on the machine? Install the new ones once I have the new chain on?
The rule of thumb is the first change chains and sprockets, any worn out roller, second change chains, sprockets, rollers and idlers, new track adjuster seals, you don't put on new chains with worn sprocket rims. HT
Actually you do what you wish when it's your own iron. The issue of worn sprockets and new chains has been covered on here many times. It is easier to take the pads off the chains while installed on the machine and it is also easier to put them on with the new chains installed on the machine.
Yup, for an excavator I wouldn't hesitate to leave those sprockets, obviously on the old chains at least, they wore a hell of a lot more on the inside than on the outside of the bushings.
Hi Guys. Thanks again for all the great advice. I am going to start with replacing the chains. Its possible once I get it apart I will find something else that needs replacing but am hoping not. The new chains and bolts have arrived. They came with 38 links and not 37 as specified. I assume I will just torch a link off? The parts manual says 37 is the correct number.
You might want to wait on removing links until after you have tried them on your machine or at the least count the number of links on your old chains. If there is an extra, make the supplier remove it. Burn any paint at all and it will forever be out of warranty should something unforeseeable happen.
If the new chains came with a press/drive in master pin kit, AND you find you do need to remove a link, then you can press a pin out, or as you say, torch things until you can remove one link. Be aware that the bushings extend into a counterbore in the links, so it's usually best to slice through the bushing and pin just inside the links on the open end of the chain near both links, then remove the right and left links with the bushing stubs, then cut the pins stubs back, blow through the center of the pins, let them cool, then pop them out with a drift and hammer. If your new chains have alligator links, all bets are off, you will need to do some pressing.
Oh boy. I dont know which king these are. I will send some pictures of the new ones. It did come with a small bag of parts. Which I assume is the master . My tracks are definately 37 links and the new chains are 38 links.
Will either be pins, spacers, and seals, or bolts for a split master (alligator style)
I meant to say which kind not king.
This is the type. I am wondering if I can weld up a drift on a long bar and pound a pin out? Or are they just too tight for that? I call the Cat dealer I bought these from and they offered to send a field tech out to press them out......but I would have to pay for that. Nice.
Those aren't Komatsu tracks and that's not good or bad. The tracks on your machine are likely Komatsu tracks and they will have a press in master pin. Don't bother with the expense of pressing it out. Take a torch and burn a ring around the center of the master pin on each side, let it cool and you will be able to knock the pin out with a punch and a 4 pound hammer. As far as the extra link goes on the new chains, check on what you ordered first and then if you ordered chains with 37 links, inform the parts people of that and ask what they intend to do about it. If you have never worked with track chains before, don't undertake the process of making in right on your own. The new chains have T headed master pins so they are not press fit. When you are ready, clean the the goo off the pins, lube up the pin bosses with antiseize and pound them in. There will be a cotter key that goes in the cross hole at the end of the pin. Don't lose it and don't use one that you get from a hardware store if you do lose it. Good Luck!
Hi John, Yes I checked. I ordered 37 link and they delivered 38 link. No they are not komatsu parts. Its becoming very difficult to get parts for the machine now. I tried to find a new ring gear for the machine as well as a governor arm spring assembly and both are NLA. Now I would need to buy a whole fly wheel assembly to get a new ring gear. I am still working on getting the Cat dealer to rectify the situation. Still waiting for a answer.
Yeah, leave the open end with the master links as is, that's a typical Japanese excavator master setup with the T headed pin. On the other end get the second link setting on hard steel or a big balk of wood with the pin and links and bushing of the first link hanging in air. With a BFH and a good drift, you can probably pound the pin out of the upper track link, might have to work on the bushing as well, what you're trying to do is get the upper link completely off the pin and bushing, then the lower link with the pin in it will just fall away, or at least that's the plan. You can always torch it off, but I hate to waste brand new parts that might come in handy some day if a link breaks.