D7-17A Final bearing adjustment help

The cage is a slip fit in the holder. The holder (with clamp) is keyed to the dead shaft with keyway normally in vertical position. Looks like the key may be out of position, sheared or missing???

This may be because of several things. Someone wasn't paying attention when they pressed in a new dead axle. The dead axle became loose and they tightened it in the wrong position or the dead axle may be broken or loose now.

Back off on bearing adjustment and check the dead axle nut for tightness next to the diagonal brace under the mainframe. If slightly loose you can probably turn bearing cage to proper position and tighten the dead axle. Then readjust bearings. If very loose and sloppy, you got problems as the dead axle is supposed to measure a certain length from the mainframe when tight.

Old magnet should have the proper dead axle measurements but checking that means a complete tear-down of final drive.

Is what your calling the dead axle what the service manual calls the sprocket shaft? It looks like to me the sprocket shaft goes from the center of the tractor, through the diagonal brace, and out to the outer bearing assembly on the outside of the track frame. It looks like this shaft does not turn, but rather the final drive gear/drive sprocket turns around it. Am I reading the book right? I've obviously never had one of these apart yet. It seems like the sprocket shaft/dead shaft should not turn, and also hold the bearing cage holder assy from turning also. Trouble is, my dirt shield looks like the bearing cage holder has been spinning, as the clamping bolt appears to have caused a ring of wear on the inside of the dirt shield. I hope this makes sense, I can get some more photos tomorrow if needed. Please help!!!

Yes, that's what I'm calling a dead axle....I haven't worked on one of these final drives in 30+ years and long ago gave away all the books on them but do remember things about them.

And yes it should not turn. Maybe the previous flat spots on the nut and bolt was caused by wear from the cage spinning and not grinding by the previous owner.

I think you need to cut the track, drop the track frame, remove end cap, remove axle nut and pull the outer bearing cage assembly off so you can check the key and key way in the axle as old magnet suggested.

You should removed the suppert cap and removed the spocket shaft nut after removed the 2 bolts each side from the support and after removed the diagonal brace cap with 4 bolt and jack the dozer and the support should be losen from the track frame and you can removed the support and the holder ass .and you can see were is the probleme

All good advice....you probably should be on the look out for a new/used holder and dead axle. If the holder has been spinning as we suspect the taper fits are going to be shot regardless of key/keyway issues.

Thanks guys, this sounds like its going to be a bit of a job. I appreciate all the advice. I'll keep reading the manual, but basically it sounds like the dead axle is held from spinning by the bearing support that bolts to the outside of the track frame- does that sound right? It looks like it has both a taper fit and a key way.

The dead axle is kept from turning by the fact that the dead axle is pressed into the mainframe and locked in place by a cicular nut with snap ring next to the diagonal brace under the tractor. If broken or damaged, it has to be "pulled" out.

If the axle has been turning (spinning) in the main frame, that's a major problem to repair and is hardly worth it for a tractor of that age. Other than that, there should be plenty of used parts available somewhere to fix it. There were a lot of those final drive parts that were interchangeable between D-7's from the 7M, 3T, 4T, 17A series.

Pretty good memory there Old 3T...
Same dead axle 2F7507 for the 7M, 3T, 4T, 6T, 17A
Same holder 1M8969 for the 3T, 4T, 6T, 17A.

Be a shame if the axle is loose in the case, doesn't happen all that often but does happen, agree that would pretty much be curtains for that old iron.