I have a d6c, 10k-3438 leaking on back side of sprocket,ck oil level and found very low..I added four gal,s of oil and noticed oil pouring out of seal on back of sprocket, Blocked up tractor, removed outer cover and found, dead axle nut loose, proceed to dissemble right side,final, found holder support pulled off by hand.Pressed off sprocket,, removed cover, and found bearings pitted but still intact,, My concern is dead axle key way is at 7:00 instead of at 12:00. I don't know if axle has turned, or if last repair someone ser axle at 7:00, Also big nut under tractor had no wire ring, but it did have lL shape pin on top side of dead axle holding nut in place. IT does not appear that axle has turned or pin would have fell out.please help thank you
TC Tractors Tony Coates will be able to tell you what’s gone wrong. It sounds drastic unfortunately
You have a loose Dead Shaft as nobody would install one in the wrong set position, press on and see what you find.
I have seen an experienced mechanic pull a turned dead axle and just replace it, I have also seen the same mechanic pull a turned dead axle and he got in a line borer and bored and bushed the dead axle housing as the taper was damaged. Either way you will be pulling it. As you probably know, there is a dimension there to measure as to how far in the axle goes. And that is about the limit of my knowledge on them.
I've seen the line bore the case and making a tapered insert to press into housing you will need a pretty good machinist to get it right so the shaft ends up at the right lenth out from the case .
I took a measureme nt before I pressed axle out, My service manual says from case, steering clutch to support on end of alxe inner edge, should be 13" I have 12",which makes it shorter, which should tighten final drive, not loosen and cause a oil leak at seals.I attached
That dosen't look bad enough to loose a inch I think i would make sure i measured from right location
COULD THE OUT SIDE end of axle with taper end and key way be worn, allowing support to go on too far, and maybe I LOOSE AN INCH there, I verified with cat tech, I am taking measurement at correct locations.
Does anyone know the size of the taper on these shafts? And what the thicknesses are supposed to be at the start and end of the tapered area? Knowing this should inform you if your deadshaft if the correct one at least. Losing and inch is a lot of wear but I don't see it being worn that much from the pics.
We always measured from flat at outboard side of shaft behind outboard threads to machined surface of the clutch housing. The questions that pop into my head are was the outboard hub tight when you took it apart did you have to use a press to pull the dead shaft and my other thought would be was inner nut tight? To be short a inch I would think you would be close or out of treads on inner nut
both out side and inner side nuts were loose, also outer holder assembly pulled off by hand on dissembly, I did not have to press if off. I did have to use press to remove sprocket and I had to use press to remove axle assembly
A couple more thoughts If I remember right most of axle/dead shaft instalation instructions tell you to press dead shaft in hold pressure on shaft tighten inner nut then drill new hole for lock If you only have one hole I would wonder if it was put in right last time also I would be looking for a part number on dead shaft/axel to make sure it right one for your machine who knows what was done to it in 60 or so years
In the circled yellow in the attached photo below, is that a wallowed out area from wear? You can see the original machining marks on the taper on one side, but they are worn away on the other. As for the inch. I think it may be you were given the wrong measurement or measured from the wrong place. An inch less then it should be would mean massive track frame misalignment, and I doubt you could get an inch out without the diagonal brace bearing hitting on one side of the machine frame. I do not know what the D6C manual says, but the D6D manual says to install the outer support hub and you use that to measure from. D6c Dead axle repair | Forum - ACMOC The Antique Caterpillar Machinery Owners Club (ACMOC) was founded in 1991 by a small group of enthusiasts who all shared a similar passion, the legacy of antique Caterpillar machinery. www.acmoc.org
I thought it was only the later machines with threaded holes to attach the pressing tooling to you pressed them in. The two bolt holes in this D6D final drive are for attaching the tooling to. I remember reading a D7F service manual and it said to flog them in with a hammer (you flog a tool threaded onto the end, not directly onto the threaded end) with someone tightening the inner nut with each blow until a dimension was reached.
Yes some of them were sledged in till you got to the spec lenth
I think I have found cause loose adjustment nuts on final drive bearing.I had posted that on dissembly outer holder pulled off by hand, The key way broke allowing support to turn on axle ,support is pinned to inner bearing adjustment collar, there fore backing off bearing preload,, Looks like I need a new axle and holder assembly
I would like to thank every one for your valuable knowledge and experience, i have ordered parts and I hope every thing will stay tight.
Im also currently working on a D6C, and having issue with the bearing adjuster nut is contacting the guard on the sprocket before Im able to get the Nut tight that holds the holder to the dead shaft. The machine does Not have threaded holes to press the dead shaft in, so we pounded it in. My manual only gives measurements that require the pressing tooling to be installed to make a measurement. Would It be quite easy to pound the dead shaft in way too far? Going by how much threads stick out under the machine compared to the other side’s dead shaft it looks very similar. How to measure it to know of its in the right depth? Any help is much appreciated. 76A 419 SN.
You need to pull the outboard hub off and adj back they are a little confusing they don't turn the way you think they would to tighten the bearing load. first you tighten dead shaft nut at out board hub making sure it is not loading bearings After dead shaft nut is torqued at outboard hub and adjustment nut still turns you can now adj bearing preload. As far as the dead shaft as long as bore in case is not all screwed up it would be pretty hard to go in to far I beleve the old ones told you to have someone tighten inner nut while you sledged shaft till you got to spec I would thing they are the same pressed or sledged
Thanks for the reply, the problem Im having is as I try to tighten the outer nut down to tighten the hub the adjuster to set bearing preload is essentially getting clamped between the steel wire guard on the sprocket and the hub. So before the outer hub is tight, the bearing adjuster is jammed tight. See pic
The guard on sprocket looks thick to me I remember them being a not that heavy
Did the sprocket push on to the correct dimension? When I had to replace the bull gear hub on my D6D, one supplier told me they tested each aftermarket one they sold (just by laying a master part on and measuring a dimension) as they had experience of some aftermarket parts the tapered spline not being made correct. HeavyEquipmentForums
Thats one thing I wondered too, these aftermarket parts could simply be made wrong. The sprocket is pushed on to the point that it is within the specification that the service manual gives. Albeit it is on the shallow end of the spec range it is still within spec. The one thing I did notice is that the amount the bearing adjuster nut is machined back where it fits into the guard on the sprocket is less than the same nut on the other side. I will post a pic, but my thoughts are perhaps tolerance stack up is partially at play? If the dead shaft was in a touch too far, and the sprocket was not quite on far enough, and the Adjustment nut isn’t machined quite enough, all together it adds up to it doesn’t quite fit.
See the red portion of the picture. That distance from the bottom of the notch, to where it meets the guard is 1.125” before its stepped down to fit into the guard. On the other side of the machine, that distance is about 7/8”, and there is nearly 1/4” Gap between the red portion of the picture and the guard. No where close to touching the guard. So my thought is take the nut back off and machine the step further back to get the clearance I need to finish this job.
Here is a used spare I had in the shed. Should be about a 1/4" gap. This photo is of a machine equivalent to yours.