Idler shaft bearing on the Power Pro???

[DLB]

Getting back to an earlier post:

Moved the rpms up to 9500 ran for five minutes and the idler shaft moved inward about a 1/4" and the bottom pulley moved toward the motor an 1/8"... The movement of the motor pulley seems to be the main problem with the movement of the idler shaft.

Do you know what parts of the idler shaft moved? In other words, did the eccentric move, did the bearings move inside the eccentric, or did the shaft assembly partially become disassembled?

Also, I'm not clear on why you believe the the motor pulley moving was the cause of the idler moving, rather than an effect caused by the idler moving? Clearly, neither should have moved but I would tend to think that the one that moved furthest also moved first or was otherwise less resistant to moving.

Two more things I would look at: 1) The three shafts need to be parallel, so I would check the tension adjustments on the motor mounts to make sure they are all equal in terms of how far in or out the 4 screws are in their adjustment range. 2) I would make sure that you have the 'right' type of eccentric bushing on the idler. I think that is the split type, and I think you can see the split from the outside with just the belt cover removed. (I'm only going by the pictures, but I don't see this part included in the PP kit.)

-David

[godavid2]

David, some people have had the problem with the movement of the idler shaft and motor pulley and some have not. The idler shaft as one piece moves and not the eccentric bushing when the motor pulley moves and rubs against the motor itself. It must be a common problem that SS is aware of since they have a write up in trouble shooting the PP ie tightening the motor pulley set screw. Apparently SS also knows about the troubles with the motor pulley shaft being out of round causing movement since they sending me one at no cost to me. I think too that SS is sending the motor pulley out of a good will gesture because I have had to spend quite a bit of money on my pp in the last couple of months. Control panel and also a new idler shaft. They did not say so but SS does not give out free parts. Thank you, Shopsmith!

[JPG]

No, but historically SS is quite diligent about replacing defective parts!!!

[godavid2]

Thank you, JPG, I was not aware that SS typically replaces defective parts. It would have been really really nice if SS had replace the defective PP Control board. But no sure luck.

[JPG]

Thank you, JPG, I was not aware that SS typically replaces defective parts. It would have been really really nice if SS had replace the defective PP Control board. But no sure luck.

That is a 'problem' with electronic parts. Impossible to ascertain they were defective. Assumption made is they were ok when shipped and got 'damaged' later. Not always accurate.

[JPG]

Us ignorant folks need pix!!!

[DLB]

Us ignorant folks need pix!!!

I'm borrowing a pic from another thread referenced earlier, credit rjent:

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To my recollection, it was not clear or determined whether that is a spacer or just a larger diameter 'tween the bearings. Therefore not clear, at least to me, which direction the inner bearing is removed. But, my educated guess is that the pulley has to come off in order to remove the inner bearing, i.e. not a spacer.

- David

[JPG]

Still no indication of how the pulley is secured to the shaft.

May be 'force' fit.

[dusty]

I am betting that the bearings are pressed on from opposite ends and that the pulley is pressed on after the bearing on that end

The diameter of the shaft is the same at both ends (.667") and the shaft between the two bearings is .750".

The two bearings are the same (6903Z) 17mm x 30mm x 7mm

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