Why are the pins ground down? I'm new to the dozer, so please forgive if it seems like a juvenile question. Both tracks are like this
They are rubbing on something. Must be a roller or rock guard. Check along the bottom and see if there is something bent or broken.
Probably rock guards all right, from the look of those some big rocks stuck in her.
Be careful of sticking your hands down there. I'm thinking ten thousand razor blades being pulled off something hard.
Is this a high drive machine and if so are both inside and outside of pins wearing?
It's a little hard for me to tell from the picture, is that scraped metal showing? or white powder from crushed rocks?
Yair . . . Double post.
Yair . . . Something out of whack with that picture . . . those tracks haven't been working, they still have rust on surface of the rails. The picture is inconclusive, weird is how I'd put it. Cheers.
Your prob right,I bought it on auction..Both sides of outside tracks are like this..I think machine Sat for a while then owner decided to get it running to sell. Very little wear on pins. It's shiny metal, not rock powder
Post more pics of all the undercarriage parts. Could be a bushing out of an idler etc letting it favor on side then the other.
Not a high drive, I also notice a few sprocket teeth broken
my guess is that they stole the good tracks off of it and thru some junk on it, i have seen this a few times on cats at auctions where pins and bushings and sprockets and rollers are dragging in strange places.
Another pic
Post some good pics of: - 1. Sprockets 2. Carrier rollers. 3. Track rollers. 4. Front idler (from closer up that the photo above) 5. Lower roller guards from front or rear of tractor, whichever is best, to try to show if the track pin ends are rubbing on the guards. What machine is it you bought..?
It's a jd 450c
Bottom rollers are worn out is my guess.
I tend to agree with you, Bottom roller wear usually results in the links contacting the rock guards. The idler in post #13 looks pretty poor to me, but the photo isn't really taken from close enough to be 100% sure. That's why I asked for more photos showing the rest of the undercarriage components.
How hard are the bottom rollers to replace..are they worn because they no longer have the proper height, or worn because the bearings are no longer good?
My dozer is about 75 miles away from me right now, so I can't get anymore pics till the weekend..also the pins have no wear on them???
No worries, unless that is you're planning to work the machine a thousand hours or so between now and taking the photos. Post the photos when you can.
Could be the equalizer and swing frame bushings are shot too, making the frames splay out when its pushing. That will make the pin bosses ride the rock guards.
I did have a ton of play where the c frame connects to dozer, the inside support had come unwelded, which only supported the pin/bushing on one side, instead of both..causing blade to have excessive play and pivot
In order for track rollers to cause wear like that I would have to assume the flanges would be completely gone, since the pin bosses are not worn from hitting the edge of the flange... Doesn't seem likely to me, but pictures will tell the tale.
Yair. . . Things just don't add up to me . . . this could be an interesting can of worms. Cheers.
As worn as these are it seems that there has to be something that is just as worn somewhere that is rubbing. Maybe burying the blade to get weight off the tracks will show the cause.
That's not the news I wanted to hear
What flanges are you referring to
Yair . . . Bloody hell this isn't rocket science. If the O/P lets the grease out of the adjusters, pulls the idlers back and jacks the tractor up on blade and rippers it would be as obvious as dogs balls. No rippers? Well back the sprocket onto an eighteen inch log or baulk and lift the front up on the blade and have a look at the flanges on the rollers . . . perhaps some bodgie or bent rock guards have been fitted or welded on crooked or some such, it will be easy enough to see. Cheers.
Flanges are the outer parts of the roller on this single flange roller. Double flange rollers have another set in the middle, the links ride between the flanges. I have never seen any case where the flanges were gone, unless something was very wrong with the track frame or idler alignment. Rollers usually wear where the links ride, making the center smaller over time and the pin bosses begin to hit the flanges. You never know though what a machine has been up to, so it's always possible you have a roller or two gone South, but both sides at the same time? Maybe the chains are running half off at the front or rear, got a link down in the center? Seen it happen if things are worn enough... that idler looks like it's out to the bitter end of adjustment so..... Usually obvious though. As Nige sez, more pictures please!
Both tracks are doing this, I'm betting it's got rails from another brand of machine that was a "close" fit and they are just too wide across the pins. Look at the overhang on the idler and roller.
You know it's hard to tell from the pictures but my first thought was that the links looked way big for a 450.
:beatsmeLooks like someone's builtup the leadin plates and used too thicker material
I'm with Scrub jack the dozer up and find what is loose or what is rubbing. I had the same rub on my chains (not near as bad though) we kept running it because there was no noise. Well it starting sqeeking and we found the problem yesterday. Bad front idler and bad front roller on LH side of machine. I think the idler took the roller out. Chain was rubbing on the rock guards because the idler was loose and let the track adjuster kick over a little. I'd jack it up loosen the track and go over everything with a little pry bar.
I've had rubbing like that in days gone by, my cause was a combination of snaky tracks and roller flanges worn thin letting the rail rub the rock guards. I just ran it until undercarriage time
I do have a broken idler on the right side, do you think it would cause issues on both sides?
Another view opposite side
Your idlers don't match wear wise side to side for one. The broken idler is def causing that side chain to be rubbing. Start looking for undercarriage parts.
Can't I repair broken idler by welding it?
My instincts tell me that the more you look at this one, the more you will find that is used up. I am thinking a complete undercarriage rebuild is in the near future and I would bet you will find cracks that need welding and broken guard bolts.
x2 I'd check all the mounting hardware from the track frame to the cross bars to the main frame. Those rock guards will unbolt with some muscle and you can inspect things alot better. Good luck!
That track adjuster rod is a relatively inexpensive part, I would buy a new one so you know it's straight and strong, I think there's two seals for it should be replaced at the same time. Don't get too excited about the undercarriage, a bit of thoughtful study will lead you to what needs to be corrected or replaced. A bit of grinding on the pin ends needs attention but not panic. It's what, a forty year old machine? Bound to need a little love to keep it going.
Seconded. The left idler is worn like a razor compared to the right. However see below ...... It may be possible to weld if it is the shaft from the idler frame back to the tensioner/recoil mechanism that is broken, however I would start by trying to identify WHY the shaft broke in the first place. Also price a replacement and then ask yourself if you can weld it cheaper/better than replacing it. It could have broken due to excessive vertical play in the idler guides caused by a combination of poor maintenance and/or wear. Like others here I think it needs a look at the complete undercarriage system, starting with the track frames, equalizer bar & pins, and the rear track frame pivots, because if there is anything major there then one or both track frames are going to have to come off for a start. At the same time you could start looking at the condition of bottom & top rollers, idlers, & sprockets. Lastly the tracks. I know zilch about the JD450 so I have no idea if as others have opined that the tracks are incorrect. Maybe it might be an idea to find some marks on the sides of the links to see whether or not the tracks are even the correct ones to fit the tractor, because if they are wrong then it would be nonsense to replace damaged sprocket segments for example. This tractor is not necessarily going to be a money pit, however it looks as though it's in need of some TLC in the undercarriage department. I hope you didn't pay too much for it. If the undercarriage is in that sort of state it makes me question what the rest of the machine is like..?
Just a note for those not familiar with this make and model, the track adjuster rod is solid where it goes into the yoke and acts as a piston rod, but is welded to a pipe section which is why you see the chrome part near the yoke and a rusty rod further back. They almost always break at the weld when the idler brackets get worn and the idler starts to move and twist, very common.
From failure to correctly shim/poor maintenance then..?
I just replaced my yoke and rod for a 550 jd for about $450 bucks. That's brand new no messing around with old welds. Also, bottom rollers were about 125 a piece this winter and actually seal kits from jd weren't to expensive either for the tensioner or the rollers. Jdparts.com will give you prices if it's still available but most importantly it will give you part numbers to search for parts.
Exactly Nige, or possibly a broken recoil spring at the rear putting an angle on the back end of the rod. There's typically a sheet metal cover over the rear section so you don't see it until things start looking knackered.
Well, I can blame anyone, but I feel the seller should have been a bit more honest about the description..for instance..it wouldn't steer at all, so I tore into it and found that the brake levers were frozen in the engaged mode top steer and I'm guessing the wanted machine to move so they used the cog wheel to loosen up brakes to get it moving and were too lazy to fix..so if I had to guess, they gave the machine very little attention....it starts right up and has good power, I'm hoping I can give it all the attention to get it the way it should be...honestly the tracks scare me, since I've never worked on them before. I might have paid too much, but it's done..I paid $9k
No that sounds like a fair price unless there's more wrong with it. I see these going for around $15K typically in good condition.
If it was in an auction you have to live by the good old motto "buyer beware". If a buyer isn't machinery savvy they should take someone with them who is to look at the machine before bidding. Don't worry about never having worked on undercarriage before. There are plenty of people on here with loads of experience who can guide you through the process. It's not as difficult as you might think but really needs to be done in a certain order. Get yourself registered at jdparts.com to find parts info for your tractor.
Thanks for all the great info...I guess I should've mentioned it was an online auction about 1200 miles away...nonetheless is mine now
Ok, I'm back to my dozer..this is what I found...the suspected idler rib is about 11 mm narrower that the idler on the other side, and the rails over lap it..it looks like it doesn't even belong on this machine.....they are over $500 to replace..I think I'm going to rebuild it..I have decent welding skills...how hard is it to split the track when I can't find the master pin?
Maybe you can find a used one rather than rebuild that one. I just ran into a similar deal with one of my front idlers. I called a local dozer shop and he had a used idler and track adjuster assembly. It was in the same shape as the other side on my machine. I picked up the part for $350 and was back going in a day or so. It will take allot of welding and grinding to fix that one.
Look for a link with a split down the center of the chain to find master link. The grouser pad bolts hold the link together. Mine was a pain to get apart but finally did after soaking it with BP Blaster and little hammer time.
I don't think they've made those cast idlers in forty years, look for a decent used fabricated one like you have on the other side as JS300 suggested, would be my advice as well.
What you have is a $1,500 dozer. I would not spend a dime on it til I knew that the reverser pulled when it got up to temperature. Those tractors are notorious for the frame breaking where it attaches to the finals. The undercarriage is sho nuf ugly but needs run to find out the condition of the motor and reverser. I would be getting my money back.
That's a little harsh. I believe a new idler can be had for 500$or less that will have a warranty. If you look at the time to re weld and cost to fit new bushings on the axle it would be about as easy to buy a new one. My thoughts are if you re weld then you might loose an axle and then its junk. Splitting the tracks is not a big deal either. I like to break them on the idler then use a 6x6 to hold the bottom part of the chain up and a ratchet binder or come along to pull the top of the rail back in place. Clean all the contact areas good with a buffer wheel. Does the tractor have other issues?
How can I lose an axle if I'm going to weld up the front idler? This is the biggest issue...other issue I found is small radiator leak..I ran this machine for about 1 1/2 hrs and it had plenty power in forward and reverse. As for a $1500 machine???? well I'm not sure the poster has any knowledge of heavy equipment machinery or is qualified.
https://g.co/kgs/dfgnH0
As for radiator issue, it was just a loose clamp
You won't actually lose the axle as far as it being gone from your presence. These things tend to break after hours of fatigue. And there are bearings the axle runs on that wear as well. Point being , I hate to see you spend 20 hours welding and grinding to have another idler issue.
You can lose the bearings on anything that rotates, and that idler has been rotating off and on for decades. That's why we're advocating a new idler assembly, or good used takeoff. You might put in all the time and effort to weld that up and then a month later find it's turned into a cow bell. Or not. YMMV Yeah, what Dickjr said, lol
Can I rebuild idler, and put new bearings, bushings and seals? Or is it not cost effective?
I think how you go about the repair depends how how much you plan to use the dozer. If for a couple hundred hours of personal use a year I would say repair it cheap as it breaks. If you really need it to run you would be better off fixing it right wich always seems to run into alot of money. Like I said in a previous post I just fixed a similar deal. I really needed to take an extra day and about another $1,200 to repair it correctly but I only plan on using the dozer for another 100 hours or so this year. Hopefully I can find the time to repair it right this winter. I would find some used parts and slap it back together undercarriage work is tuff, mainly due to all the old fasteners not wanting to come loose. I'm learning that if you don't like to spend money on repairs dozers aren't for you, especially if you have to hire the repairs out. One thing to keep in mind is what it would cost to hire a dozer operator to work for you. In my area a 100 hp dozer is around $125 an hour. At that rate you can work the repair cost out of a machine pretty quick....if you have the place to do it. Just take your time and enjoy doing the repairs as I'm sure this won't be the last one.
Thanks, my dozer is purely for personal use. My livelihood is in the healthcare industry..I like to tinker with things and give them the tlc they need..an easy way out is to spend $7k and put new tracks, front idler etc, but that's not what I prefer to do right now..in that case, I'd run it til tracks fell off..to me it's fun and a hobby..I enjoy welding and I'm a third generation welder, so my belief is "if its human made,a man can fix it"
Or a man can spend an hour searching online, and swap out that old junk for a used part that was designed for that machine, rather than "trying to make a silk purse out of a sow's ear". As for value, there's a big difference between what a desperate novice will pay, and what a veteran WOULDN'T pay for a solid older fixer upper. Fair market value is somewhere in between. Just because it was sold/purchased at auction, doesn't mean it can't go for more than it's worth. The way I look at it, half the stuff at auction sells for more than it's worth, and half less.
A few years ago I needed a front idler for my 450C. I shopped around on the internet and found a good used one for around $350. If you are set on welding your up first see how much you are going to have to built it up and how much time and cost it will take you. But first take it apart and check the inside where the bearings and races are. If it is wallered out forget it.
Yep, I think you're right. I went back and looked and those rails don't look like they belong to the tractor. That idler rib has been chewed off on one side indicating at some point that the track was not running true. Here's some parts machines: http://www.machinerytrader.com/list...ction-equipment/manufacturer/deere/model/450c I've been to the 3 in Texas and they're OK to deal with. They'll have most any parts you would need and save you a lot of money with used stuff.
The master pin on that old of a dozer will have a dimple or small hole on the end. You have to beat or press it out. Oh I just thought that won't help you ends are chewed up. Are they chewed up on both sides?
Correct if the tracks are correct for that machine. They did not bolt those 550 tracks together with longer track pad bolts. I spent some serious sledge time getting my old ones beat out between grinder runs trying to get all the weld cut off! Personally, I would be looking for a new idler and new rails at a minimum. Once you get the track split I'd start looking at bottom rollers to see if any of them are OEM that can be refilled and check to see if the bearings are any good in them.
Well I've figured out the problem. I need 10 bottom rollers and an idler sprocket. Im going to replace rear sprocket too (has some teeth broken). Those bottom roller bolts are very stubborn. Im having to heat them and use impact.
By "idler sprocket" are you referring to the front idler that you have been disassembling recently..? TBH I would not recommend you replace the drive sprockets because of the broken teeth until you clear up the doubts raised by others who are not sure that the tracks currently installed are the correct ones for the machine. If you simply replace the sprockets for new ones they could be destroyed in short order by tracks that could be of a different pitch to that of the sprockets. If the tracks are in fact wrong it may be that they have caused the broken sprocket teeth, so replacing both sprockets and tracks would be the only way to solve the problem long-term.
Nope, I have measured the rails and according to the service manual they are within spec. Also if the tracks were wrong, i would think both sprockets would be broken up. IMO the previous owner was really bad about maintenance.
From the photo in post #51 on a previous page it appears as though the bushes are significantly worn externally. I have no idea if this photo is from the side with the damaged sprocket or not. Just out of interest what measurements did you take on the rails that showed they are within spec..? Could you post some photos of the sprockets on both sides of the tractor so that we can see the condition of them..?
Bushings are good. I will take pics tonight when i get home.
How have you determined the bushings are good and the pitch is correct? Have you measured across 4 links to see what the wear is? I agree with Nige the bushes look to be worn.
Yes, as in my post #72 the measurement is 25.53" which puts me right at 70%..as for the culprit,I pulled rock guard off and I could see where rails were rubbing..the rollers were shot...so I'm going to replace all rollers, front idler and sprocket..I'm not a business or do dozing for a living, so I can't anticipate thousands of hours..some of you are perfectionists and that's great, but this machine is old and I think I'll get my use out of it
Sorry to disappoint you, but we work on yellow iron for a living, it's hard to be perfect in that line of work...... what we are trying to do is to help you establish the condition of the complete undercarriage on your machine and hopefully make sure that the route you're proposing to go on replacing parts is not going to come back and bite you in the *** at some future point because of some factor that wasn't considered.
When writing post #77 above I forgot to mention that if as you say the pitch extension on the current track links is around 70% then installing new drive sprockets that are designed to work with links that have 0% pitch extension in them is likely to cause very rapid initial wear of the sprocket teeth until the bushes on the current "extended pitch" links fall into the sprocket teeth correctly. You may be able to live with that but I mention it in passing anyway. The normal procedure to solve this problem provided the track link surface wear is within acceptable limits would be to turn all the track pins & bushes 180 degrees to bring the track pitch back to specification. At that point the teeth on new sprockets would marry up perfectly with the track pitch, if that makes sense.
Nige I really appreciate and value your input. I totally understand where you are coming from, but I can live with an initial rapid wear of a $130 sprocket, vs the economics of turning the pins and bushings..and from what I have read for my machine its more feasible just to replace with new rails. I dont need to do that just yet. I think with the new roller, idler and sprocket I can get plenty use out of it. I found shale rock stuck in some rollers and tension spring, so I am under the assumption that prob something like that caused teeth to break sometime back. Thanks again!
Based on past experience I'm not a fan of turning pins and bushes whatever the cost, I prefer to run the links to destruction. Best of luck with your plan.
I'll post update when Im done