# Back gear assembly?



## Dark Age 53 (Jan 14, 2015)

I was looking over what's involved in removing the back gear assembly, I've seen video's on how to but my 1928 SB 22 YC seems to be different.

I understand on how to remove the lever, the two square headed bolts but I don't see any pins on the shaft that need to be removed.
Here's one video showing the tapered pin I'm talking about, at the 2:00 minute mark https://www.youtube.com/watch?v=lCpuSCdlF8U .

A few pics of my set up, you can see in one photo a missing gear tooth.


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## timvercoe (Jan 14, 2015)

It looks to me like you have the tapered pin but the pin is just about the perfect fit and the head and the tail are hard to see.  I can look at my SB when I get to the shop and see if it is different.  It is quite a bit new than yours, 60s machine I think.  You might try cleaning that collar really well and see if you can see the ends of the pin.  I am a little confused by the slotted cover for the shaft on your machine, just have never noticed it my mine has that.   

Tim


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## Dark Age 53 (Jan 14, 2015)

timvercoe said:


> It looks to me like you have the tapered pin but the pin is just about the perfect fit and the head and the tail are hard to see.
> 
> Tim



Tim,

I'm new to lathes so I very little, I'm really not understanding what you're saying. There's a tapered pin in the lever handle which I see, as for the pins that are shown in the video, I don't have those pins.....I'll get a better pics showing that area. Thanks for the reply.

Later,
Al


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## Dark Age 53 (Jan 14, 2015)

More pics.


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## Ski (Jan 14, 2015)

Could it be that the older lathes have no pin ? The 13 does not have a tapered pin on that part. My old 65 vintage 10L did. Try to pull the shaft out with the handle after the pinch bolts are out. An older parts breakdown might shed some light ob this too.


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## Ski (Jan 14, 2015)

Take a look at the "useful files" section at the top of the south bend forum. If you look there is at least one parts list from 1935 and while I am not 100 %sure,  it does not seem to show show a pin on the right side of the back gear.


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## Dark Age 53 (Jan 14, 2015)

Ski said:


> Try to pull the shaft out with the handle after the pinch bolts are out. An older parts breakdown might shed some light ob this too.



If you look at the first pic I posted I think you can see you can't pull shaft out from the handle end, the eccentric bushing also looks different then anything I've seen posted.


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## Ski (Jan 14, 2015)

Dark Age 53 said:


> If you look at the first pic I posted I think you can see you can't pull shaft out from the handle end, the eccentric bushing also looks different then anything I've seen posted.


Not sure how else it would go ?If that


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## sundownj (Jan 23, 2015)

Hey Dark,

The left end of the shaft with the split eccentric bushing (little gear end) is driven out by using a round nose punch in the direction of the handle end.  This, of course is after loosening the two square locking bolts you show in the photos.  Actually you can remove them completely.  Each eccentric busing has a round indentation indicating where the tip of the locking bolts (which should come to a point) are supposed to set when tightened, this correctly aligns the eccentric bushings allowing rotation of the shaft when engaging the back gears.

In your 1st photo posted, it shows the spot for the placement of the round punch so damage does not occur to the handle shaft (smashing or enlarging the shaft).  It is not necessary to drive out the pin holding the handle on the shaft as seen in the video you posted. Nothing on the handle itself is used to retain the shaft in place with the exception of the pin allowing the slight rotation of the eccentric bushing and should allow the handle eccentric bushing to be withdrawn at the same time.  If for an reason this bushing is stuck, then you may have to remove the retaining pin first, like shown in the video, leaving only the bare shaft.

By removing the shaft, the housing containing both gears is lifted straight up and out of the fixture.  My 13" SB has the gears on a key way on this type housing and both can be removed from the housing using a small hammer and block of wood.  On a side note I do have a 20 ton press if they get ornery.  None of your photos are clear enough to determine how your gears are attached to this housing but they should be the same.  Inside the housing there should be bushings (probably bronze) in each end that the handle shaft rotates on but not the entire length of the housing.  The inside center of the housing has a hollow space for oil.

Also, in one of the photos there appears to be 2 fittings "marked with the number 710" and should be places to oil by depressing the centers, which should have some type of spring closing.  This is how the handle shaft is lubricated.  My 13" SB has a center screw that is removed for oiling the shaft.

I have seen the gears I believe that will fit you SB available on ebay and other places on the internet, separate and the complete assembly when I was searching for my 13" SB back gear unit.

Since the shaft has probably not (or maybe never) been removed for some time, don't use a sledge hammer on the round punch, go easy. Watch the shaft for movement as you tap. If no movement occurs, stop and seek out a more knowledge person for assistance.           ..................sundownj


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## rafe (Jan 23, 2015)

Is it 710 or OIL ? All depends on how you look at it !


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## Dark Age 53 (Jan 23, 2015)

*sondownj*, Thanks for the great information on to remove gear assembly, the only thing I might add is spraying some PB Blaster around the bushings and let it sit for a day. Again, thanks for the detailed information. 


*​**rafe*, Your correct, it does say oil. I took the pic at the bad angle. Thanks


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