Power feed won't run when quick change gearbox is engaged

I looked at the 9249 manual... and I pulled the cover off and took a photo of this one:
IMG_20210716_205837.jpg

In the top right you can see the shift fork, and it moves well and engages either the gears behind it (threading leadscrew) or the gears below it (power feed). That seems to all work well.

What doesn't make sense is that with both shift levers disengaged like this, power is fed through the shaft above the shift levers. I would've assumed that there were two separate shafts, left and right, and that power would only be fed through the shaft that the shift levers ride on from the left to the right, but that doesn't seem to be the case. The G9249 isn't set up like this, not exactly, at least.
 
Not familiar with this lathe, but I’d wildly guess that the bearings have seized together in the red center support on the upper shaft.
 
I would surmise that what Rabler mentioned, as I was writing the same thing. The gears should move freely and independently from the 5 on the left and the 8 on the right side. Most likely they are not working independently as sets.
 
Is it likely to be a single shaft or two independent shafts? The gears on the left side (input side) all turn at different rates, while the gears on the right side all turn together, as if they were keyed to the shaft. I'm wondering if a bushing on one of the left side gears just got stuck on the shaft...
 
I would guess that something is wrong in the shifting mechanism. Causing 2 gears to engage at once, locking the rotation.

Chuck
 
Looks like bearing balls and considerable metal in bottom of box. Can you determine origin?

Chuck
 
They're just chips that have fallen under the box. Definitely there aren't two gears being engaged simultaneously; for some reason the left and right sides should be independent, but aren't. I don't know if that's because one of the left side gears is frozen to the shaft (it'd be the farthest left one) and it shouldn't be, or whether there are two independent shafts that are frozen together.
 
Most Norton style gear boxes are all the same. There are two shafts. The left side is the input shaft with its 5 gears and the right shaft is the output with it’s 8 gears. You will have to remove one or the other to see if a key or pin has shifted, seized bearings, etc.
Pierre
 
There's a hex screw holding a washer on the left side of the gearbox; if I take that out, can I just knock the shaft out toward the right side?
 
There are quite a few videos on dissembling lathe Norton Gearboxes, might be worth reviewing first. I would remove the whole gearbox and do a complete disassembly as opposed to trying to do it in place. They remove quite easily. The shaft is a single unit, the 5 gear cluster spins on the shaft the 8 gear cluster is keyed to the shaft. It sounds like the 5 gear cluster is seized to the shaft, often 2 gears are attached (see video). You may need to press out the shaft. It looks like there may not have been enough lubrication to some of the gears.
 
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