Hello I have an old D4C CAT which I use on my property for general levelling work. During my last use, the machine separated between the leaf spring and undercarriage, that is it has come of the leaf springs at the front on one side. The leaf spring now hangs below the track and the front of the track points outward, I thought no problem, I would buy the new tie bolts, lift the front of the dozer and hence the leaf spring by putting the blade down on the ground and then turn the other track to push the machine over so the leaf spring was back on the undercarriage. Great idea, however it did not work, pushing the blade down also lifted the front of the tracks. Next idea was to try and lift one side of the dozer, again no luck. Unfortunately the dozer is in a muddy area on a slope, about 1 km from the garage..... I thought that before I break something or injure myself, I might ask how one generally might approach putting the leaf spring back on the undercarriage. Any information would be much appreciated.
I hope this photo helps - it shows the leaf spring and the undercarriage.
i think you have diagonal brace problems , called alignment arms in the picture https://www.dropbox.com/s/21ijk4eim9iq4hu/brace.jpg will also pay you to check the bolts that hold the saddle to the block , these are known to crack around the block ,if they all come out you will find yourself skyward
Yair . . . d4dozer As the #3 post says I reckon some thing has broken or come a drift to allow that amount of movement . . . I'd be checking the outer sprocket support bearing setup too but I am not conversant with your tractor. Cheers.
I'm with the guys above. Your photo shows a symptom, not a root cause IMHO. The root cause is going to be found somewhere at the back end of the tractor. Getting the spring back in will probably happen while you are pulling the track frame off, because I think you'll most likely end up having to.
Thanks for your thoughts, this is the location at which the machine died. As you can see, I managed to move it of the road, but it is now impossible to move as the track is touching the body.....Nice mess, literally - as its pretty muddy. A great spot for a first time disassembly. So the verdict seems to be that I need to pull of the track frame and see what's happened at the back? Has any one every used the air cushion jacks under a machine like this? The ground is way to soft to put a jack down, even with a plate. Thanks
Any decent size trees around..? You're going to need lots of timber cribbing.
I was thinking of getting two 4tonne air bags - lift one side and then chocking it, but its so dangerous though because any point to chock is so far in and I don't like the idea of putting my body under there...
Like said above pull the sprocket covers and check the saddle and bolts like in Niges pics then the inner wishbone bolts and cap their supposed to have two bearing shell halfs in there that are supposed to be greased but Ive seen them when they hadn't been and if it wears on the shaft you have big problems. Final drive has to be pulled and the dead axle replaced and like you said that aint a good place to do it. Im going from memory but I think the leaf spring just sets on the roller frame might have a bolt and tube above it that lets it pick up the track when you raise the dozer with the blade.
goofed didn't think the post went thru
Rather than repair the machine where it is, can the track 'structure' be pushed / wedged / pulled into some alignment, then temp weld some tubes / pipe / plate to hold it there, then drive /tow it back to the truck / shop. I have no idea if this will work, but I keep this one welding machine around basically just for this purpose: machine rescue. It is a small 8kw welding generator and I figure that will be its calling. These machines can be rented - they make power for tools, lighting, and a small air compressor as well as make some stick welds....
I like your thinking, but the end leaf spring is in the way of pulling the track in. So if I could get it back on the leaf spring if could move it.......which sort of goes back to my original question. How do I get the leaf spring up.....Airbags? So the idea would be , get the leaf spring up, straighten the track so it drives (and temporary secure it), take it up the hill to the garage were I can work on it, then follow steps given above?
Yair . . . d4dozer . Mate I wouldn't even think about trying to move it until you get a firm handle on the problem, you are likely to tear the guts out of something. From your picture you are in a pretty good position right along side a decent gravel track for goodness sake. It's a little D4, no big deal to jack it. As Nige mentions you are going to need some decent baulks/cribbing. There looks to be a bit of timber there, an hour with a chainsaw would cut a decent selection. All you would need are a couple of ten ton jacks and a bit of patience. Be careful, think it through and work safe. Incidentally this is a "breakdown" and rarely is it possible to conduct such repairs in a work shop. The normal situation is the back of the tilly serves as a work bench and tarps are rigged to protect personnel and components from rain . . . if it pi$$es down some strategically dug trenches may be necessary to divert water around the site. Cheers.
If you can jack that spring up you may be able to rig some chains to hold the track frame into position so you can move it to your shop. A jack under the front of the engine should eventually bring that spring up. Take a quick look under the back end and see if that diagonal brace is in place. Good luck
Do you know what might be just the thing to get the track frames back apart and the spring back where it should be..? A couple of Acrow props. However I bet that there won't be any available out in the bush where the machine is, if there is any sort of construction going on there just might be. Most people will ask what an Acrow prop is. Google it - there are loads of images. I'd think that if the blade was used to gently take the weight of the front end of the tractor a couple of props between the 2 track frames should be all it takes to push them apart enough so that the machine could be raised up until the spring is lined up. Release the props and the frames should come in and hold the spring. Bob's your fathers brother ....
It looks to me like the spring has spat the dummy out, these springs are made up with a multi leaf build up with the 2 longest leaf sections sitting on the saddle section of the track frame, the leaf sections are clipped together useing 4 "Fox Clip " ties 2 each side of the centre mounting pin, your jacks are on the blade, just lift your blade right up and place timber baulks under the blade, press the blade down and the result will be good, crib under the nose group for safety and sort out your knackered spring, you will find the end worn off the 2 main leaf sections, if you were in the U.K. I have a rebuilt spring ready to fit, the Fox Clip clamps are rivit fastend to the leaf section and the multileaf build up is clamped together through cast steel sections with nuts that near always undo, the centre pin will be worn out and look like a chunk of Camshaft, failing finding a good/new pin a welder can soon shape it up, allow a day to get the job sorted. tctractors
I actually have about 15 Acrow props.......The problem is the tracks lift with the front of the machine when the blade goes down.
Crib up on both tracks till you get above the hood lay a beam across and pull it up with a chain hoist then pull the tracks in ,with the blade & tracks on the ground we are not talking about a lot of weight here on one end of that spring.I will try to get Willie to come sit on the track and pick the thing up. hope this helps
Willie been taking vitamins or eating bowls of steroids?:beatsme
Hi.. could you please to check your PM.. thanks..
Yea he started when the tomcat ran him out of the excavator.
ointlaugh
The Spring lenght tip to tip on a D4C like a 24A series tractor is 4ft 3"(1.300mm) your spring might be missing the last 4" on the 1 side,it might be time to trade up to a D6R and put the D4 on the "job to do spot"
Would love to, been dreaming of it, but D6's in Western Australia, even if they are almost dead cost you an arm and a leg......and then some. Someone I know imported one from the US and got quiet a bargain, compared to local prices. I will have to try and fix mine. Has anyone tried the air bag jacks? I am waiting for the rain to stop before attempting the look see investigation - we have had some mighty wet weather here in WA.
Yair . . . d4dozer An exhaust jack was standard in our Suzuki Sierra when we were poking around on compass bearings on the Gulf coast . . . got us out of trouble a few times, I have never really thought about using them on heavy equipment though. Cheers.
Well the mud has now gone in WA, but the little D4 still sits waiting. I am going to try air bags and see if I can lift it. It is one of those daunting tasks, well for me anyhow.
shop guy - I have read your post a few times, trying to get my mind around what you propose. What you are suggesting is to put a beam, reacting on the tracks and use a chain block or the like to pull up main frame while pushing down on the tracks with the beam. Then find a way to pull the tracks in. sorry for repeating it back to you, but I do not do this sort of thing very often (ever....) so am a bit cautious. cheers
tctractors - thanks for your comments. I did try using the blade to lift the front, but for whatever reason both the dozer nose AND the tracks lift at the front when the blade is pushed down, leaving the "relative" dimensional discrepancy in place. (This old D4 does not have non return valves on the hydraulics so it is really dangerous to lift the front and get out of the machine......) I undid the leaf spring clamp on the other side in case that was dragging the tracks up, but that made no difference.
well after spending many days trying I am still as stuck as ever,.......my latest plan is to try to undo the alignment arm bolts.
Well over twelve months of trying, I finally got it back in today.........and drove it back to the shed!
Ok, ascertained that the leaf spring is in fact about 50 mm shorter on the side that came out. I am going to try to put a mild steel extension piece in on one side only. Getting a complete leaf spring here in WA looks to be an impossibility, so its time to improvise.
Yair . . . d4dozer Mate, that does not make sense. You need to pull the thing apart and figure out the problem. You have a broken or worn pin/centre bolt, slipped clamp or something . . . I just don't see how that assembly could be asymmetrical unless some one has hacked an end off the main leaf with a gas-axe. Cheers.
It is shorter on one side because then end of the spring broke off!
That'll do it every time......!! I'm sure there must be a replacement spring out there somewhere though.
Is it common for the ends to break?
Good Spring works {makers of truck springs ** should be able to make you a new Spring Leaf I know on larger dozers than D4s the springs were replaced with a solid bar ..Perhaps Scrubpuller may be about to shed a bit of light on solid bar replacements .
Scrub Puller, a solid bar or even a thick walled SHS section sounds appealing? Anyone else done this conversion, lets face a D4C is a pretty rough ride and the suspension is only protecting the structure from impact, not the driver.....
Yair . . . d4dozer . On the Allis HD21s we used to weld all the leaves together to make it into a solid unflexing equalizer bar. . . I can't recall any issues and it could be worth a try. Still can't get my head around breaking a couple of inches off the end . . . did it wear very thin then fail? Cheers.
one thing to keep in mind with the D4C and making it a solid unflexing bar is that the saddle is fixed to the block and it has no chassis or frame unlike the D4D ,they are well known for cracking the mounting holes in the block
The ends breaking off these springs after many years of wear is fairly common in the U.K. I have the complete assembly including the saddle mounting and pin ready to fit all refurbished, but the postage might be a drama? I did say in page 2 that its most probably the tip snapped off, the thought of all the nose weight thumping into the cylinder block takes some understanding in CAT engineering as near every block I see on this series of tractor is damaged. tctractors
I thought the springs might be there to protect the machine rather than the operator......breaking the block does not appeal to me.
I've often wonders why they're wasn't a bushing or shackle setup on the ends of the spring, but I suppose the engineers didn't expect the tractors to be in use 50 years later, so weren't worried about the springs wearing thin and breaking.
I would suspect that the spring is set up to support the weight of the motor, and that's about all. I cant see that any other loads can be transferred, so the alignment of the tracks is an unintentional load transfer that results from worn "other parts" that in the past kept the tracks aligned? Any thoughts?