D5B Final Drive Leak, I think.

[Costnsg]

I bought this old D5B about 3 months back and I've been working on it (on and off) ever since. Good news is I'm retired and have time for that. Bad news is I'm not an experienced dozer mechanic. I bought it to help clean up some property I own. I have fixed several leaks now and changed most fluids and filters. Haven't touched final drives...yet.

Pics are attached that illustrate leakage from right rear of tractor. I haven't removed the dust cover for a closer look yet, but I can see the leak is outboard of the sprocket and somewhere around that big nut. I'm thinking to try adjusting the final drive bearings to see if that helps as the next step. The manual says this is a maintenance procedure that should be done every 2000 hrs. Based on the degree of neglect I see overall on this machine, I wouldn't be surprised if it was never done. I can also see a little oil residue/dirt mix on that nut on the opposite side, but no sign of serious leakage there. If the leaking side benefits from bearing adjustment, I should probably do the other side as well.

Curious to hear if my approach makes sense to you guys, or is this an automatic tear down that I need to accept? If I attempt the bearing adjustment, I have a few more questions I will add in another post (same thread).

 

[Costnsg]

If I proceed to do a final drive bearing adjustment, I'm thinking I'll need to break the track. My manual says it's possible to do without breaking the track, but it requires special tools that I don't have.

I'm attaching a pic of a spanner wrench that appears to be what is needed. Am I on the right track? I'll have to buy one unless there is a different way, but this one's not expensive. Also including a pic of the master link so you can see what I have.

Manual suggests the track be separated at the rear sprocket and reassembled at the front. Is this what works best for those who have done it?

Manual also says to tighten the big nut to 2400 ft-lbs and then back off to 350. My skinny self on a 10 ft cheater pipe is only 1500 fl-lbs. How is this best accomplished? Is it really necessary to apply that much torque? I wonder if the spanner wrench can stand it.

I assume I will also need to get all the load off the sprocket beforehand which means jacking up the rear of the dozer (a little) on that side after the track is off the sprocket.

Lastly, there appears to only be about 7/8" for the track adjustment piston to move for loosening the track. I suppose it must have been enough when the track was last installed, but that track looks pretty tight at this point. Any concerns?

 

[Costnsg]

I also found a heavier duty version of the spanner tool from OTC. Perhaps this one is up to the task.

 

[.RC.]

This might help

 

[LarryH]

You shouldn't have to break the tracks to adjust bearings. The heavy duty spanner (7309) is what is called for by Cat.

 

[Costnsg]

Larry, I think I'll order the wrench and take another look with wrench in hand before I opt to break the track. I just don't see much room to maneuver that wrench and get the adjustment made with that track in the way. Have you done it successfully that way? That experience is what I lack on this exercise. I expect to change that by about week after next. Thank you for responding!

 

[Costnsg]

This might help

RC, I was hoping you'd weigh in with your thoughts. I did actually find that video and it squares well with the instructions in the manual. I think for the price of the spanner wrench I'll buy one rather than make my own. I don't have a big pile of scrap metal and buying the material will cost me about a third of the new wrench, I figure. What do you think about my prospects of fixing my leak by adjusting the bearings only? I guess I have to at least try and see if it will work. I have no odd sounds or feel from the final drive, just a leak.
As for the manual's suggestion to torque to 2400 ft-lbs and then loosen and retighten to 350 ft-lbs, I'm not sure I'll get it quite so tight as 2400. 350 is no problem.
Thank you!

 

[LarryH]

You will need to remove some track plates to gain access to the nut. Its not a big job. You just need a6-8 foot pipe for the wrench. Make sure you turn the nut in the right direction. I have done it before but its been a while so memory is a little fuzzy.

 

[.RC.]

Have you put a crowbar on the sprocket to detect sideways movement.

You will also need a big socket to check the tightness of the nut on the end of the dead axle.

You have to loosen off the slotted nut first, then check the tightness off the dead axle nut, then retighten the slotted nut.

Do I think it will stop the leak. Probably not, but it may do enough to get done what you want to do with the machine. Any metal in the final drive oil?

I heard a story about a D8H that was leaking so much oil someone (who I suspect had no idea) told the operator to put some really heavy oil, nearly grease like stuff in it, not sure if they ever did, but I heard someone tightened the bearing adjustment nut up and the leak slowed down considerably.

Also keep in mind if oil can get out, then dirt can get in. I recall Nige mentioning in here with oil sampling high silica levels means dirt, or sand really.

 

[Costnsg]

Larry,

I don’t know why it didn’t occur to me to remove track pads to gain access. I’m away from the house just now, but I will look at it when I get home with that in mind. If I can get on that nut with the wrench against the outside of the track rail it should work. Thank you for that suggestion.

RC,

I haven’t checked the oil yet for metal. I have oil to change it out and figured I’d wait until I had this leak addressed (if I can) to change the oil in both final drives. That is the only fluid I haven’t changed at this point.
I’ll pull that outside plate and measure the dead axle nut to see what I need there. I’ll either order a socket or maybe I’ll have a friend who owns one I can borrow. It will be next week before I get the spanner wrench anyway.
When I’m ready I’ll loosen the track, jack up the rear, and check for sprocket movement.
I really appreciate your feedback. Together with feedback from others, this forum has been very helpful to me in the short time I’ve been involved with it.

 

[Costnsg]

RC,
I think there is a message in your questions. I tried to get some side movement on the sprocket with a pry bar and it didn't budge. The track is tight and the weight of the dozer is on the tracks as well. If I release the tension on on that track, get weight off the sprocket, and still can't get any side movement on the sprocket with a pry bar, is that a good indication that I'm wasting my time trying to adjust the bearings?
On a positive note, I checked the oil level in the final drive (why does that plug need to be so dang tight!) and it's almost full. No way of knowing when the previous owner may have filled it, unfortunately.

 

[Nige]

As others have suggested personally I would take a look at the oil first. If it is full of sparklies then you know you are in for major disassembly and that attempting a bearing adjustment would probably cause more problems than it solves.

 

[Costnsg]

Nige,

I already have new oil that I bought with the assumption that I would change it (as with all the other fluids), so I’ll drain it and take a look. If I catch a quart or so of the first oil out the drain is that satisfactory for examination? Manual says it holds 3 gallons.

 

[Nige]

I would drain everything into one container, then you can go rooting round into what you’ve drained out. Don’t forget to keep whatever cones off the magnetic plug(s).

 

[tctractors]

Have you put a crowbar on the sprocket to detect sideways movement.

You will also need a big socket to check the tightness of the nut on the end of the dead axle.

You have to loosen off the slotted nut first, then check the tightness off the dead axle nut, then retighten the slotted nut.

Do I think it will stop the leak. Probably not, but it may do enough to get done what you want to do with the machine. Any metal in the final drive oil?

I heard a story about a D8H that was leaking so much oil someone (who I suspect had no idea) told the operator to put some really heavy oil, nearly grease like stuff in it, not sure if they ever did, but I heard someone tightened the bearing adjustment nut up and the leak slowed down considerably.

Also keep in mind if oil can get out, then dirt can get in. I recall Nige mentioning in here with oil sampling high silica levels means dirt, or sand really.

There is no bearing adjustment nut on a D8H, it is a shimmed pre-load on the outer cap.

 

[tctractors]

To adjust the preload on the D5 you can split the track or whip off a few track plates, its better to split the chain as you can jack up the tractor and spin the sprocket for the best results, remove the lock off the big toothed adjuster and fit in your new OTC C spanner, you will want to pop off the outer cover end cap and make sure the lock is in place on the dead shaft nut, the lock fits on pins on the dish that loves loads of grease, anyhow when you are standing at the back of the Tractor looking forward as in the seat the right hand adjuster is pulled towards the back to tighten, so with the spanner on the top of the adjuster you pull it down towards the back, the left hand side is pulled from the bottom towards the front of the Tractor so you are tightening the collars, its handy if you can spin the sprocket after you have adjusted the collars just to check that they are firm, the OTC spanner can take some hammer but be careful as things slip, I have an OTC hook with a bit ground off the back to fit in the collar more positive. best of luck.

 

[.RC.]

There is no bearing adjustment nut on a D8H, it is a shimmed pre-load on the outer cap.

Ok I remember seeing photos of one apart now. A big roller bearing on the inside and a tapered rollers on the outside.

 

[Costnsg]

I drained the oil from the leaking final drive today. I didn't have a low profile container that would fit below the drain point and still hold all the contents, so I pumped a couple gallons from the fill opening into a 5 gal bucket and drained the remainder into a plastic pan. You'll see pics for both containers below. I didn't find anything in the oil except the fine particles mentioned below.

I also looked closely at the drain plug and what was sticking to the magnet. It was a mushy blob of stuff that looked similar to what was attached to the strainer magnets for the drivetrain when I cleaned it a few weeks back. It's very fine metal particles mixed in oil. I stuck my finger into it before I took the pic and there's about half an inch of it on the plug. I also took a putty knife and spread it on a white panel. That did not reveal any large pieces. Only fine particles.

I poured some oil in a glass jar to see if there was any sparkles when the sun hit it. Didn't see much of anything that way. However, after I poured the contents of the pan into the bucket (consolidating the oil), I noticed there were some fine particles in the bottom of the pan that did reflect sunlight. To me it seems similar to the particles stuck to the magnet on the drain plug. You may also notice some larger "bumps" on the bottom of the pan. I believe this to be some dirt that fell into the pan as I was removing the plug. I tried to avoid that but was not 100% successful. I'm attaching a short video as this captures the sparkles a little better than a still shot. Hopefully it will upload and you are able to open it (large file).

I refilled the final drive with new oil and plan to drain and change the other side tomorrow, weather permitting.

Feedback on this step? Any conclusions based on oil examination?

 

[Costnsg]

More attachments...

Well, I wasn't able to upload the video clip. Not sure why unless it's a size issue. Also not sure whether the forum allows videos to be uploaded as this was my first attempt. Anyway, I did describe what I saw in the post above.

 

[Nige]

Also not sure whether the forum allows videos to be uploaded as this was my first attempt.

You cannot upload videos directly. You have to host them somewhere else and link to them.