I need to replace the sprokets on my 550 John Deere dozer. Are there any special tools needed, and what is the best way to do this. I have never done this before so I know I need advice from someone who has done this before.
tracks Have never done it on a JD only high track cats with bolt on sprocket segments. All we ever used was a socket and ratchet with about an 8 foot cheater pipe but if you have to take the track apart I would have a couple of good come-alongs and have the rear end off the ground so u can spin the tracks back on the sprocket possible have a chain hoist or a skid steer to do the heavy lifting
Only machines I've done undercarriage on are our TD-15C's and CAT 312 excavator. For the 15's, took the blades off, got the entire machines blocked up, rotated each track so the master link was right in front of the sproket(that way all the track rolls forward), removed a few pads, then using a track jack(picked up from army surplus years ago) to hold it while you removed the pad holding the master link. then just let em roll to the front. The sprocket on the 15's is all one piece, bout 12 bolts and its off. After were done(usually are putting on an entire new under carriage) set the machine down on the rails and get a few links grabing on the sprocket and just drive forward. Get the tail on the front to flip up over the idler. Using the track jack, or come alongs pull the master links together. I have to look in my collection of photos to see if I have any with the tracks split. It also helps to loosen up your front idler to give your track as much slack as possible. Hope that helps some Trbo
Thanks for the information guys, I think I will be able to get this done. I wonder why all dozer sprokets don't have the bolt on segments instead of replacing the whole sproket?
Remember to loosen the tracks first :cool2
I will be sure and loosen the tracks, thanks for the reminder. I had another track guy come and measure my tracks today and he told me something that doesn't make sense to me. He said he would just replace the sprokets and keep running it without having the pins and bushings turned, he said and I asked him twice to be sure I had it straight that if I had the pins and bushings turned I would only be getting about another 100 hrs. of use out of the tracks with them turned. That has got me confused, granted if you knew me that don't take a whole lot. Heres my confusion about the situation, if it takes around 1500 hrs. to wear out one side of the pins and bushings why would the other side only last you such a short periond of time? If he is correct why would you bother ever having them turned? Looks like a lot trouble and money for just a 100 hr. of running time.
dry or lubed tracks?
Sprockets As I was told, the biggest reason, the sprockets are in segments, is so you can change them in the field, without breaking the track. I personally, dont break, or loosen (unless its real tight) the track when replacing the segments. If you slack it off, all the way, you stand a chance of the track falling in your way. I move the machine, where you can get to a segment, remove the bolts and replace them. Its better to have a big impact (3/4 drive) and a good air source. I like to replace the nuts and bolts (most of the time, the nuts get messed up) they dont cost that much. Get them from the dealer, so you get the correct size and hardness. Just keep moving the machine and replace them as they come up. After you finish, check the tension on the track. This is not a bad job, if you have the right tools. I have had to (in the field) to torch the nuts off and replace the new bolts, and tighten with a cheater bar. This is my second, same reply to this post, so if another one pops up, it was my internet problem. Good Luck
Here's my theory. If your tracks are dry, the worn space between pin and bush are left as a space (open gap) after turning. This space soon contains abrasive material which acts like grinding paste on the remaining turned pin and bush. If you're lucky enough to work in topsoil all the time the opposite will apply. I had an oval track D7G LGP that used to work in sand and water most of the time, and I tried TURNING the SALT (sealed and lubricated tracks) only once. The sealing surface was at the end of each bush and failed ones (aprox 50%) were replaced to ensure the integrity of new seals. An expensive exercise which resulted in buying new chains in the future, then running them to destruction. Three good men could fit new chains and transfer the grousers overnight under the sky when required. This machine was on 24 hr hire and had a 12hr window each week for major maintenance. Sprocket segments were replaced with the tracks in place at any other time. I found that the sand used to pack around the low drive sprockets and cause too much grinding when bushes and sprockets were both in new condition........C ya..........Ray
If the tracks are dry they are out of pitch from normal internal wear that will accelerate wear on new sprockets that are in new pitch if not turned. If they are lubed the internal wear is not a factor. Pitch is the distance center to center of the track pins as a dry track wears this distance incerases. Are you more confused now?
Not many people can predict the life on pins and bushings after turn. There are so many variables; working material, steep ground, high speed reverse operation just to name a few. As DPete says the issue of dry or lubricated does make a difference. Because lubricated track does not stretch if the oil is still in there, the bushings wear and the pins do not. Most owners and operators don't keep a good watch on how much the bushings have worn and consequently they wear past the point that they can be turned. They wear so thin that when pressed they crack. If you have worn that far it is best to just install new sprockets and run to destruction. Mr. Welsh also has it correct in stating it may not be economically feasible to turn SALT track bushings because of the extra labor it takes to install new seals, refilling the links and then pressure testing to be sure they don't leak. It has also been my experience that the track shops only press one side of the link apart so one seal does not get changed. Since SALT track is basically all master links, when the oil is gone the track is shot in no time at all. A sealed track will stretch with the idler being adjusted out to keep the track adjusted. When the idler reaches the end of the track frame it is obvious to the operator or owner that something needs to be done. The stretch roughly coincides with the wear on the bushings. At that point you turn the pins and bushings and replace the sprockets and go back to work. From my experience you only get about thirty percent of the time you had before turn depending on how long the operator can stand to run it. You haven't stated what series or year your 550 is. I've seen a lot of problems with Deere SALT tracks wearing out completely with less the 2,400 hours on the clock.
Back when I was younger(just a lil kid) I know I asked my dad why we never did pin and bushing turns. His reason was just as you stated, we ran Sealed and Lubricated Tracks thus the cost would could not be justifed. I do belive we could get 3500 to 4000 hours on a set, so about 3 years max. Trbo
DPete they are lubed tracks.
Thanks to all of you for your help and advice, I think I will go with the new sprokets and just run it some more. The dozer is a 2004 550H. Now I know why everyone has to charge so much for dozer work. It's about like fertilizing hay fields, with the price of fertilizer these days I feel like I have got the tractor window open and am throwing $20 bills out the window as I am going over the field with the buggy. Like my cousin told me ain't nobody but the Corp of Engineers and the State got enough money to run a bulldozer.
Like John C and the others said. I just run my lubicated track to the end and never turn the bushing.But i just work in the mud and black dirt.If sand like in Neb. i would run the min. then do a early turn of the bushings and run them out. Here the seals will go first and oil will leak out before the wear on the bushing are a problem.Dry bushing are worst then bushing wear,at least for me.With dry bushing the tracks strech out fast and you run out of tighten ability. On the D6H you can only tighten so far they fixed it so the grease will leak by because they put a groove in the tighten to keep you from running the idler out to far and getting more wear or breaking the tube because of the length it is extended. Your new sprockets will wear really fast if you have any dry bushing,so don't plan on getting to many more hour for the money you put in the sprockets.Is you sprocket really pointed or chipping, because you can run them longer if they are pointed or chipped then you can if the rails are getting streched to the max,is worst. Do you think you have more tighten length and what about dry bushing? Well good luck:usa
do idelers get turned or built up, what might that run?
The tops ones we always just build up and run them until the bearings go out, not a huge deal to change, just did one the other day that went out and it was only about a 20 min job(tracks were off so easy to get to). Not a bad price either $240 for a new one. The rest will be built up next year as they still have build up on them from the last time. Bottom rollers we have gone both ways, if the tracks are off for another reason we have slid them out and built them up otherwise just replace them when you do a full UC. Good safety rule, when the tracks are split and you are re installing them be aware they can move and buckle between the top idlers, front idelers etc. Trust me I know, as it happened yesterday and my right hand got between two pads and smashed my fingers. trbo
im kinda new to tracks.im thinkin of bying a 93 d6h undercarrage is shot but comes with 50%chain and roolers. lose .the front and rear idler wheels would stay but are groved. would i take a grinder to them? on unit.? bring um to a shop? thats a lot of grinding.
John Deere Sprockets A friend of mine runs these Little John Deeres and he thinks the John Deere Sprockets are worth the Extra Money. He buys almost all of his parts from Heavy Quip but the Sprockets don't last very long. Sprockets are one thing he gets from the John Deere dealer.
Without seeing photos of the idlers I would be thinking welder before grinder. Put some material back on them don't take any more away. Lets see some photos of the grooves. Trbo
O.K., Bandit, you're in Luck. I work on 650's, same as your 550, just a little bigger. You will need: blocks to support rear of dozer, and two blocks to put under the blade. Come-along or chain hoist, a section of 2-3-inch Bar Stock, and a block to hold the track against the idler for reassembly, plus assorted sockets and impact or ratchets. A torch(Depending,) a lot of Anti-seize, and a big Torque Wrench. Block up rear of dozer, and put a block under each side of blade. Jack her up, and find the Master links. Remove the grease fittings for the track tensioners. Take your short section of Bar Stock and stick it into the teeth of the sprockets so it will support both sides of rail(track chain). Spin track either way, bar stock will ride around, catch the rail, and as it passes around it will suck the tensioner in. Now you're ready to break the track. Spin the Master link to the rear of the tractor and break the track. With the dozer in Neutral and brakes Off, hook your pickup or Farmall to the track on the top side, and Head Out The Door with it. That done, time for the Sprocket. NOTICE; There are occasionally some thin shim rings on the back side of the sprockets, DO NOT DAMAGE/LOSE THESE! They are critical to aligning your sprockets, don't mix them up, either, they go right back on the axle they came off of. All Cases have these, JD not so much. No idea why Deere won't use segmented sprockets, probably to make more money off you. Get your screwdriver/scraper and knock all the dirt off your roller frames, and check the 8 big bolts that hold them on the crossbraces CAREFULLY, the bolts break REGULARLY, and many times will only have a shred of steel holding their heads on. Put a socket on ALL of them and put a little torque on them in reverse. IOW, back them out if they will and LOOK at them. NEVER put these bolts back in without Anti-seize, if you do, you WILL be Sorry. You will probably need to change out a few rollers, if you're not doing a Full Track Rebuild. Check ALL your roller bolts, and if you have Rock Guards, check the bolts on those, as well as the crossbars that connect the guards. These will get loose and wear in the holes, and eventually decapitate themselves. Now, if you ARE going to replace all the rollers, a NOTE: Go ahead and pull the roller frames, MUCH easier to work on, Worth The Time. Turn the roller frames upside down, and pull all the roller and rockguard bolts. You WILL break the heads off MANY, if not ALL of them. Don't Panic, it's NORMAL, we'll FIX that while we got her apart. Check your roller frames for straight, make sure they're not spread or Forked at the idler end. This happens due to Operators being @$$hats and hitting stumps Dead Center in High. After you get all the roller bolts drilled out or get your New frames in, whichever you decide, buy a Tap the same size/pitch as your roller bolts, and chase out ALL the roller bolt and rockguard bolt holes. It seems John Deere does not cut threads all the way through the roller frame, just 3/4 of the way. THIS is why you break the heads off the roller bolts and have to drill them out. I don't care HOW MANY times you've changed out rollers, unless you do this you WILL break the heads off a BUNCH of them. Fastest way to get out snapped-off bolts is drill it for an Easy_out, then heat the side of the roller frame alongside the broken bolt til it's Cherry Red. Take a few draws off your stogie or a couple sips of coffee while it cools to normal color, THEN tap in the Easy-Out and wrassle with it. Sometimes you may have to go ahead and blow the bolt out with the torch. Needless to say, you need to be GOOD with a torch to do this. Usually bolts will come out First Try with method described. If it is still stuck after Third Try, Blow it Out with the torch. This will be a good time to Build Up the wear-places on the idler ends of the frames, and replace the wear bars, as well. As you put it all back together, MAKE SURE to Antiseize ALL bolts that screw into the roller frames. That way the NEXT time you have to do this it will only take ONE day, instead of three. Also, re-pack your track tensioners and check the rods for pits or cracks. Now, the Tracks. If your new rails come seperate from the pads, Unassembled, that's O.K. Lay the rails out on the shop floor, pad side Up. Take a grinder/wire wheel and knock ALL the paint off the pad side of the rails. They must be BARE METAL. Next, put 'em on, MUCH easier to do with no pads attached. Now, have your assistant lay out all the new pads with the grousers down. Then have him/her take the wire wheel and knock off ALL the paint in line with the bolts holes where the rails will meet the pads. They must be Bare Metal also. The reason for this is that paint on these will prevent your pad-bolts from EVER tightening up and STAYING tight. You will ALWAYS have loose bolts and pads, and they'll drive you NUTS. Do It Right The FIRST Time, and Forget about it. You must cut the paint off the inside of your new sprockets for the same reason. The axle flange mating surfaces MUST be CLEAN and BARE, or you'll go broke replacing broken bolts. Any paint, dirt, or rust on these mating surfaces will prevent proper bolt torque. And DO torque all bolts To Spec, and go over the pad-bolts TWICE. Re-torque your sprocket-bolts in two or three days and they should be good until they DO back out. As you replace the shields on the roller frames, some of them will have stripped nuts/bolts. Just get Grade 8 replacements, and Mig the nuts in position. The factory bolts are too soft, the dirt wears the heads down. Grade 8 will LAST. If I forgot anything, feel free to ask. KY Jim
Real good info gents
Need help! Which nut is the grease release on a d6h