Hello all, first post. I noticed that there is oil leaking down the inside of my sprocket, from what I’ve read I’m thinking that the duo cone seal might be bad. How do I go about fixing this. Never tore into a dozer final before. Thank you for any help. Jonathan
Post a machine Serial Number and a photo or two of the leak. That would be a good start. On a conventional tractor like yours replacing the Duo-Cone (if that's what is actually leaking) is going to be a fair bit of work.
I will get a picture when I get to the shop tomorrow late morning. Thank you
Well I walked into the shop this morning to find final gear oil all over the floor. I moved the dozer in from a job I just finished Cutting timber on yesterday, that’s when I saw a small bit of oil on the inside of track pad. I’m guessing I have the pull the final off ? Obviously I need to block the machine up and split the track at the z link. Then what? Thank you for any help and or encouragement. First year in business is always the hardest right?? Haha
Well here's what I'm seeing for the remove and disassembly of the final drive of a S/N CFC00446, D3G dozer:
Here's the track separation & connection just in case it's any use.
TC Tractors is the preferred man in the UK to be pulling finals apart. I'm sure he can give you some good advice if he sees this thread. It's not a job to do yourself. It's an idea to pull both apart.
These aren't like a conventional oval track tractor with a dead shaft and tapered splines. What you are looking at is a single stage planetary driven by a pinion and bull gear. You can dismantle it as far as the duo cone without removing the final drive and with no special tools required. However, the pinion bearings start to wear out on high hours machines so you may want to consider pulling the entire final drive while you're at it. It's up to you.
Nicky, Think TC Tractors would make a road call to Wyalusing? Maybe swing by and pick up Cmark on the way?
Thank you all for the pictures and directions. The machine has 4600hrs on it. I called the previous owner today and he said he had the local cat dealer in his area replace the duo cone seal on the other side at around 4000 hours. Both finals had good clean looking oil when I changed both around 75 hrs ago. I think im going to start by tearing into it while it is still on the machine. Once I get inside if I see lots of wear or find something broken I will then pull the whole unit off. I will keep you all posted as progress is made or lost and will post any further questions I may come up with. Thank you all!
I just took a quick look at the directions I posted and did not notice any major presses or that kind of stuff. A few special tools but seemed like most of that would be overkill for a one time project. But then like I said I just took a quick look so may have missed something!
Just work careful and keep things clean and if you need help I think someone here will chime in. One question I have. I checked just for fun as to where Wyalusing was and it appears to be just a bit down south in PA. The question is why when you do a Google Maps search on that name does it show a picture of two giraffes?
Yep, only maybe a crosshead and porta power cylinder required which I don't consider to be special tooling. You can even avoid this if you're in a pinch by pushing the drive hub off with a couple of bottle jacks braced against the machine frame.
im not sure, I googled it and I can’t find the giraffes lol
This type of F/Drive is not to bad to tackle you do not need the Patent Lift bracket thing as a single forklift tine with a clever bit of strapping will set the job free, or it can be pulled down a good amount in bits, they are similar to the F/Drives fitted to the Shovel range ( 943-953 etc) I have used simple Enerpac cylinders to pull off the hub but it could be tugged off via a few brain cells I feel. best of luck with the task and lets hope things are not damaged inside. tctractors
I split the track and pulled the segments Saturday afternoon. This morning I started on pulling the final drive assembly. And for never doing it before, it came off very smoothly thanks to all the help you all posted. Now, time to get to that duo cone seal. I got a clean tarp laid out to put everything on in order and a paint marker to mark inside and outside as needed. I’ll keep you all posted!
One thing that may seem counter-intuitive is that when you pull the two halves of the worn Duo-Cone seal out of their housings the silicone rubber rings will be drenched in oil. When you install the new ones they MUST go in without lubricant for the seal to function correctly - the only assembly "aid" that is permitted is isopropyl alcohol. Also you have to clean the housings where the rubber rings fit with whatever will get all the oil off them and treat them with the same alcohol. So you can get your head around how Duo-Cone seals work try this thread. HeavyEquipmentForums - I know it's about track rollers but all Duo-Cone seals irrespective of size to all intents & purposes function in exactly the same way. The larger in diameter you get, the more critical the installation & alignment of the seal is. There is a pdf attachment SEHS8876 (post #6, Page 1) in the thread that would be extremely good reading for you. Another point to metnion is that, once istalled, the height from the face of the housing to the top of the steel ring has to be measured at 4 points 90-degrees apart around the circumference. There is a maximum permitted height variation between the 4 points that could well be described as "not much" - it's actually 1mm or 40 thousandths of an inch. Often new seals have the plastic height gauge shown in the bottom drawing of Illustration 1 in the box with the seal.
I did not know that. It’s a good job I leave it to Tony
As Nige says the most important thing with those Duo-cone seals is clean, clean, clean! Forget what machine it was on but recall I was told that there was a problem with the surface of the area the orings went into being too smooth. Believe there was a "cure" of glass beading the surface to give a little grip to the rings. So don't polish that area just clean it good and no oil on the rings or the surfaces they touch. Maybe just one drop of oil on the faces of the two seals(metal parts).
We had that years ago on at least two 994's IIRC. Couldn't figure out why a particular Duo-Cone kept leaking on a brand-new machine even after replacing it with new. Then the factory came up with the suggestion that they'd come across some ramps that did not have the required level of surface roughness causing the Toric Rings to slide down the ramp instead of gripping it.
I chickened out. I got down to the bearing that sits on the duo cone seal. I just am not set up yet to pull bearings. So I took it to local dealer and a few hours labor later she’s back together. I brought it home and finished assembling the fd. As far as getting it back on the machine I’m having a hard time getting the two dowels, the sprocket off the motor to match the large sprocket on the shaft in the final and the end of the shaft on motor to match up with bearing in the final housing all at one while suspended off a chain. I don’t dare draw it in because I’m afraid of ruining the bearing in the top of the final. So what I’ve come up with is.... I bought a few m16 bolts 2” long. I’m going to cut the heads off, throw the now stuff in the lathe and weld on a 6” piece of cold rolled stock the same diameter. Then I’m gong to thread a few into the dozer and use them as alignment rods so at that point I can put a floor jack under the assembly to hold weight and roll in into the machine square and even. What do you guys think? Any tips or secrets?? Thanks again for the help thus far! Jonathan
AKA guide bolts. So long as they are dead straight after you finished welding what you are planning ought to work. Can you get M16 threaded bar.? Even a couple of pieces would give you something to use as a draw tool to help everything go together using the guide bolts to support and align the components. The key thing is, don't rush.
Your right about not drawing it in with bolts, and your plan will work but I would get longer bolts and cut the heads off ,using 2 about mid way and adjusting with the jack while turning the sprocket flange. when you get on the dowels you should be good to go. Bob
when I get to the dowels it stops... it appears to be lined up correctly... am I missing something?
In the picture of the machine, how do I know that the end of the shaft is going into the bearing in the top of the final assembly straight? In the disassembly procedure the last step before removal was to remove 4 nuts on the pump drive on the inside of the machine. After I pulled the final drive off I did not see how doing that did anything because the studs I pulled the nuts off never moved. Did I do something wrong here and now that’s why I’m hanging up on reassemble?? I think tomorrow I’m going to pull the final assembly off again to check that bearing in the top of the final assembly and start all over again. Any suggestions??
If its trying to start on the dowels try a bolt on each side about 2 holes down a little tighter than finger tight then one on top and tighten lightly . If the cover moves in tighten bolts evenly but don't force it. If it stops back up. The nuts you removed on the drive motors were to remove the pinion carrier Bob
I got it 1/8” on to the dowels but then it stops. I can reach in through the drain hole and wiggle the gear that mates you the pinion and sets on the shaft that goes through the final. I can also wiggle the sprocket hub. What could be bound up not allowing it to pull on that last 3/4”?
Looks like the pinion bearing would be the only thing holding it up? Back up and try again maybe put your pilot bolt on the top and start the bottom a little bit ahead of the top. Bob
All together. Ended up pulling pinion shaft and putting it in the final to hold the large gear in. Went together super easy. Spent the afternoon putting new segments on and putting track back together along with straightening track frame shields. New segments on other side tomorrow then off to the next job! Thank you everyone for your help
Always good to hear a success story. I hope you removed all the paint from the mating faces of the new segments before installing them, otherwise you'll have difficulty keeping the hardware tight.