BGB Tear Down/Fixing

[Austin]

I’ve finally decided to just go through this gearbox as I’m tired of it just sitting around being useless. The photos provided are just of my preliminary findings and what I can see as of now. I discover just rust chunks on the bottom and some water still but that was expected as the first time I drained and then put oil in this, the only thing that came out was water. Output shaft seems to be salvageable yet, no major damage appears to be there. The pto side has some minor dings but nothing too terrible. I ran my fingers across the gear teeth and I didn’t feel any catching and nothing felt sharp so I think the gears might be alright as well. The output shaft as some decent play up and down, and side to side. So it likely will need replaced. So as of now I’m think all new bearings, new seals, and a new input shaft. From memory believe I will alsoneed 3 new “moon” keys and a new retaining ring for the input shaft?

 

Also does anyone know the size of the nut in the last picture? I can’t get it off because I don’t have a big enough socket. I know it’s at least bigger than my biggest socket, 1 1/16th inch.

[dhoadley]

As for nut size, I would put a tape measure to it, read it incorrectly, buy a socket that won't work and repeat until I got the right socket. 😏

[PhanDad]

11 hours ago, Austin said:

“moon” keys

11 hours ago, Austin said:

the size of the nut in the last picture

The nut is 1-1/8" across flats.  

[Austin]

A bit more progress tonight. I was able to finally get that nut off in order to take the rest of the pulley and the side piece of the frame rail off. I had a, as my great grandpa would have called it, “senior moment”. I couldn’t figure out for the life of me why the pulley wouldn’t even budge with a puller and breaker bar. Well after breaking out the air compressor impact, I found out… Apparently there’s a set screw there that would have been nice to un-do before hand 🤦‍♂️. Found out after I got it off, I’m surprised the key isn’t as badly torn up as I thought it would be. Overall the output shaft seems to be reusable, and the keyways look fairly good. I checked it out pretty well and couldn’t find any grooves or deep marks from bad bearings or seals. The gears both look salvageable as well. I saw no excessive wear or jagged edges. The input shaft is what looks a little rough. The keyway is ok but not great and it has a slight groove from likely a bad needle bearing. Overall I think my order of all seals, all bearings, back plate gasket, retaining ring, input shaft, and all woodruff keys is still holding solid. I was quoted $276.44 for everything (that includes tax), however the input shaft is on back order for quite a few months. So I’m not holding much faith for that.

 

Let me know what you all think of my findings, and if you also think my output shaft and gears look useable. Also does anyone have advice on removing the bolt holding the input shaft gear on? I tried for a good while with no luck and that’s where I quit for the night.

[Bill725]

11 hours ago, Austin said:

the input shaft is on back order for quite a few months.

On back order "forever" as it is NLA. NOS on Ebay.

https://www.ebay.com/itm/135069481482?itmmeta=01J4S2M5XJ5PWBYC95FJWQ0PPD&hash=item1f72c4ba0a:g:49QAAOSw7SBmTLKo&itmprp=enc%3AAQAJAAAA4M%2B%2FoyEQFI0e2fS6838sYImeK0qFBtRsh1Omb2J%2B3rfX9luUeI%2B%2BpFe0brZwdt0P%2Bm4NyjMVwnbg9iH2kiYZAr9UihNC0bRVImiwh2yKh03Sdv9UqEx420hsedwkvJymdqYjFWadhuKJ7nJWiCaAh%2FewGJIR7jGk%2FsbUbNBgkTfKpu3KaPttaYRgTC4RTkyA%2BzJfP20zVVFmFm0TQypTGuR8Sln%2BTkWY6ChJmEtHqyyxhKK2hUS9UKFidMvikXd%2Bsj23SFN2lOZm93twDRj8vR0PVosjSL4t9bMTuATMBLfk|tkp%3ABk9SR-7e0KKmZA

New cross shaft on Ebay.

https://www.ebay.com/itm/256442492021?itmmeta=01J4S2M5XKWYDR1H91VA4E1QBM&hash=item3bb529e475:g:XlEAAOSws15l70x6&itmprp=enc%3AAQAJAAAAwCAT%2BrD5VdXlhffX55SZF6rm7ALdQjKLw4a3Lsm7VJDoxu4cfv%2FoC2llEDPL4SdbXzcZMlojM7Lg5ISkxntrTjXk3q8MnHU8lFlAe4Fon%2FEXRmxiRJ56lRmZeIuyGc1v%2Bfu4JjIyZG2FUb5T9oqo98QtAOYrOnARLBESoqZRccm%2BwKMnrdamZLBCvxu%2F1pyytYcK%2BDsWeQmgeZoQTWiJ7m10hJKG6FMCQV%2FswdEa3jKlMnUUR2SouHAmvVgFujLoig%3D%3D|tkp%3ABk9SR_De0KKmZA

RH oil seal also NLA. Use Timken 471733 seal with a 1-3/4" OD X 1.510" ID X 0.120" wall tubing, 0.476" long as spacer.

Most small BGB parts are NLA.

I have made several different size shaft sockets. I put a key in shaft, shaft in socket, clamp in vise and remove screw.

 

 

 

Edited August 8, 2024 by Bill725

[PhanDad]

On 8/7/2024 at 10:36 PM, Austin said:

does anyone have advice on removing the bolt holding the input shaft gear on?

@Bill725 "tool" method (it reminds me of working on my '69 Charger where the "repair" manual constantly said "use tool #xxx to remove...) is best, the Simplicity "repair video" shows a similar method:  Put a key in the shaft and clamp the keyed end of the shaft in a vice (brass lined if I remember correctly) and remove the bolt.  I think for installing the gear, you do the reverse and torque to spec.  Since I don't have a brass liner for my vice, I use pine wood to prevent damage to the shaft.  

Personally I wouldn't remove the gear until I procured a "new" input shaft. 

 

Edited August 9, 2024 by PhanDad
nut —> bolt

[Austin]

Thank you both for your input. I will look into getting the NOS input shaft off eBay. Potentially the NOS output shaft too, as I plan on installing this bgb into the B-110.

[Chris727]

That bolt on the input shaft is special. It has a thinner than typical head to provide clearance, which makes it more difficult to remove. I believe it is also NLA. 

[PhanDad]

12 hours ago, Chris727 said:

It has a thinner than typical head to provide clearance, which makes it more difficult to remove 

Definitely requires a 6 point socket. 

[dav-1]

  I have just started tearing down a BGB. I don't remember the source but it must have been sitting outside for a bit. No oil, just water. Bearing are frozen solid. I need to save the input shaft to go in another BGB that the p. o. drilled thru the shaft  after destroying the keyway. (he was into pulling)   

   Years ago I rebuilt one for my Big Ten, back when parts were available. I had photo copies of a tech sheet showing the procedure. Don't have them anymore so I found a youtube clip showing how to do tear down.  

   After this BGB, I have 2 others waiting. One is just tired but the other the cross shaft is almost out without even opening the back of the unit.

[PhanDad]

On 9/6/2024 at 9:30 PM, dav-1 said:

I found a youtube clip showing how to do tear down

Please post link. 
The site lost access to the one we had. 
Thanks. 

[dav-1]

I typed "manual to rebuild a simplicity bevel gear box" into my facebook search. It brought up some youtube videos by Ron Gundrum. I do not know how to send a link to you but you might be able to figure it out. I watched part one last night and tore down one of the 2 BGBs that I am rebuilding. The second one has a problem that I haven't resolved yet; cross shaft is out but gear will not clear input gear.

[Austin]

I’ve been meaning to ask this on this thread but have not remembered. What are everyone’s thoughts on me reusing the input shaft that came out of the gear box? Do you all think I could get away with it without any damage or would something be likely to fail? I have not been able to find a new input shaft, and I did not jump on the one on eBay quick enough apparently.. From memory the shaft didn’t have any major wear or divets but had impression of the needle bearing. Just wanting to know some opinions, or maybe if someone has an nos one laying around…

[Mikeac]

Curious as to what your working on

[GregB]

From the first post:

Looks like B series.

And Red Farmall in the background?

 

[Mikeac]

Early B10 right. Later B10s and up were black 

[Austin]

1 hour ago, GregB said:

From the first post:

Looks like B series.

And Red Farmall in the background?

 

Correct an early B-10 gearbox being rebuilt for the B-110. As to the Farmall, it's the Cub some of you have seen before. I've been meaning to make a topic about it but haven't quite got to it

[Austin]

23 minutes ago, Mikeac said:

Early B10 right. Later B10s and up were black 

Yes, an early B-10.

[GregB]

Here is mine, a 1949

[Austin]

@GregB, mine is a 1949 as well. I see yours has a fast hitch on it. I don’t believe I’ve ever seen a pre-1950 Cub with a fast hitch before. Did yours come from the factory with it or was it a later purchased piece and swapped on?

Edited September 9, 2024 by Austin

[GregB]

The history of the tractor:

My wife's paternal grand father bought it new.

My father in-law got it from his father.

He then retrofitted the one point fast hitch.

Built the mounted splitter, that we used to split more cords of wood than I can count.

When he had a dispersal auction some years ago, I had to buy it at the sale.

Also have a mounted bucksaw for it when I pull off the splitter.

 

This snap was from a bunch of years ago.  Me in the middle, my son in the picture is now thirty, and my father in-law in the picture just passed earlier this summer at almost 92 years.

[Mikeac]

We have good amount of nos 2025572 shafts that we could spare one or two.

 

sorry for your lose

Edited September 10, 2024 by Mikeac