John Deere 30 inch mechanical tiller disassembly problem

[Al_W]

I'm trying to get the chain sprocket out of the tine shaft on a 30" JD mechanical tiller. The sprocket and spindle will spin on the tine shaft and slightly move out but will not pull further than 1/4 inch. I don't see a way to get in back of the sprocket to either pull it or push it out. Anyone ever do anything similar? Am I overlooking something obvious?

 

[TractorTech]

From your description and pictures, I would say that the bearing is stuck on the shaft. Did you unscrew the set collar, #7, on the bearing?

 

[Al_W]

From your description and pictures, I would say that the bearing is stuck on the shaft. Did you unscrew the set collar, #7, on the bearing?

There is no longer a set screw on the collar and it is still stuck on the shaft. The bearing and race are mostly broken off anyway and the problem is the shaft of the chain sprocket that goes into the tiller shaft will not come out. The set collar would only keep the bearing in place and not the chain sprocket from being removed. I'm still working on it.

 

[oldnslo]

When shaft stops moving does it still turn freely? Just curious if over the years some crud has built up inside the tiller tine tube or if tube is slightly bent from use.

 

[TractorTech]

There is no longer a set screw on the collar and it is still stuck on the shaft. The bearing and race are mostly broken off anyway and the problem is the shaft of the chain sprocket that goes into the tiller shaft will not come out. The set collar would only keep the bearing in place and not the chain sprocket from being removed. I'm still working on it.

I'm missing something, but when you removed the setscrew, did you unscrew the collar from what's left of the bearing's inner race? The collar bites into the shaft to hold the bearing.

 

[Al_W]

I'm missing something, but when you removed the setscrew, did you unscrew the collar from what's left of the bearing's inner race? The collar bites into the shaft to hold the bearing.

The collar is still on the sprocket shaft but there is so little of the bearing left that with the flange bolts removed none of that--not the collar or the bearing--would keep that shaft from being removed IF it would only move freely. Anything left that is still on the sprocket shaft easily fits through the hole of the tiller side body.

 

[Al_W]

When shaft stops moving does it still turn freely? Just curious if over the years some crud has built up inside the tiller tine tube or if tube is slightly bent from use.

When I pull it out that little bit and it won't go further it is stuck at that point and will not turn freely. I'm at the point where I am almost ready to give up on it. I'd like to put a bomb under it and blow it up. Getting really frustrated because I have other things to do and can't spend all of my spare time with this.

 

[TractorTech]

Okay, so I think then that the holes that the retaining bolts go through a galled the shaft? If so, take a drill larger than the hole and use it to clean up the raised area of the shaft. To pull the shaft, fashion some wedges out of wood or stacks of metal behind the sprocket to help pry the shaft out.