# Drive gear slipping on my 1:24 Bachmann 4-6-0



## yellow_cad (Oct 30, 2020)

On the straight and flat my Bachmann 4-6-0 pulls fine, but with the slightest increase (grade, tight curve, etc.) motor revs and it doesn't move. I have been into the drive train and I can't be sure, but my best guess is that the final drive gear is slipping on its shaft. It is pressed on a weakly knurled shaft, but it likely spun once so is prone to now. I was thinking of coming into the shaft/gear joint from both sides with super glue and hope enough wicks between the two to secure the gear. Thought I would check hear first to see if someone else had this same issue and found a better solution. Thanks for any help on this. Jim


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## Nick Jr (Jan 2, 2008)

Jim, Bachmann.com, in their parts section offers just the replacement gear or what still looks like a plastic gear pressed on to the axle. If it is slipping it may also be cracked. Let us know if the adhesive fix works.


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## Dan Pierce (Jan 2, 2008)

If not cracked then try to pin it as well as gluing.


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## yellow_cad (Oct 30, 2020)

Nick Jr said:


> Jim, Bachmann.com, in their parts section offers just the replacement gear or what still looks like a plastic gear pressed on to the axle. If it is slipping it may also be cracked.  Let us know if the adhesive fix works.


I am having a problem finding the drivetrain parts for the 4-6-0 on the Bachmann site.


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## Nick Jr (Jan 2, 2008)

Could just post the link, but there are other things on their site you may find interesting. I also suggest you join the Forum, very knowledgeable folks there and quick to respond, that is where I am learning.

1: Bachmann.com
2: Parts Service and Info
3: Order Parts, (with the loco pic)
4: upper left drop down menu pic. Large Scale Parts
5: scroll down till you come to the loco you want to look for parts.
I found what you are looking for under. ANNIVERSARY then FRAME & WHEELS you will get an exploded view of the assembly, the parts are numbered.
The parts people are very helpful if you are still having problems. Direct #. 267 297 2494
I must say, looks more difficult to work on than the 2-8-0.
Also, the locos I saw the axles w gears were for the 4-4-0 and 2-6-0.


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## Pete Thornton (Jan 2, 2008)

I for one never encountered a slipping gear on an 4-6-0, though I'm sure it has happened.



Nick Jr said:


> several pages of parts that are available,


But no gears, either for the Anniversary or 'standard' 4-6-0. Usually Bachmann sells a motor and gearbox combination. I didn't see one of them either! Aha. Found the gearbox: under "4-6-0 Standard-Detail Parts" for $36. [At that price you could buy a junk one and use it for parts!]

I do not think your super-glue idea will work. Apart from anything else, that's a 'shear' joint which acc is notoriously bad at gluing. You really need a pin or screw on to a flat spot on the axle. I have managed sometimes to get a collar next to a gear and then bolt to gear to the collar. The collar has a setscrew to tighten it onto the axle.


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## yellow_cad (Oct 30, 2020)

My final drive gear that is mounted on the shaft of the drive wheels is cracked at its boss. I am not sure how the wheels are attached to the axle so I haven't forced anything in that regard. Without removing the wheels, I can't get to it to pin or sleeve. Would anyone know if the shaft is chromed thereby making it more difficult to drill? If I do just glue it, I would clean it up real good with alcohol. Anyone have an idea of what glue would work best for attaching nylon gear to steel (maybe chromed) shaft, super glue, 5 minute epoxy, Gorilla Glue, etc? Thanks for any thoughts. Jim


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## Greg Elmassian (Jan 3, 2008)

Cracked gear, replace, no glue will work, nylon not fun. Join the Bachmann forum and read the sticky at the top of the forum and then ask for help if you still need it.

Greg


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## yellow_cad (Oct 30, 2020)

I called Bachmann and they don't sell the drive gear. Their only remedy for that model is to buy a complete new chassis for $90. Worse yet the replacement chassis also has nylon gears and the metal gear chassis will not be available for about one year. Can anyone tell me how these wheels are attached to the axle so I can remove them to get at the gear?


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## Nick Jr (Jan 2, 2008)

Pete, I found an old MLS posting of yours from 08 where you inquired about removing the wheels, did you ever come up with a solution?
Thank You,


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## Pete Thornton (Jan 2, 2008)

yellow_cad said:


> I called Bachmann and they don't sell the drive gear.


Excuse me, but I found a complete gearbox for $36 - see post #6. Maybe they didn't understand which version you have.
Are you sure this is a 4-6-0? How old is it? There are 5 or 6 generations, and the latest/decent ones have a bump under the axle. Also take a look at this:
Big Haulers Tips



> Would anyone know if the shaft is chromed thereby making it more difficult to drill?


It is not chromed and not stainless. The wheels have a nylon insert to isolate them from the axle. If you have the right tools, it can be filed or drilled.



yellow_cad said:


> Can anyone tell me how these wheels are attached to the axle so I can remove them to get at the gear?


They are actually dead simple. In typical Bachmann fashion, they have a screw in the center to hold the wheel onto the axle. The screw is hidden behind the wheel insert. 
To remove the wheel insert (see pic below from Bachmann's gearbox listing,)
Gearbox & Wheel Set Assembly - Black (Large 4-6-0) [0AY01-00J05-MTG48-B] - $35.79 : Bachmann Trains Online Store!
you look behind the wheel for the balance weight. As you can see below, the balance weight is not molded into the wheel, so it is visible between the spokes from the inside. Take a small screwdriver and press it out from the back!










This gearbox may not fit your motor and the gear may not fit your gearbox! But if you take off the wheels you should be able to push the axle out of the gear and free it all up.

Post a picture or two as you do it.


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## yellow_cad (Oct 30, 2020)

Here is a photo of my final drive gear mounted on the shaft. I am not sure how to remove these wheels from the axle so I can attach a sleeve that will hold the gear fast on the shaft. The gear is cracked and Bachmann says they only supply the entire chassis as a replacement and it is $89. If I could remove the wheels, then I could jerry rig some fix.


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## Nick Jr (Jan 2, 2008)

Pete, you last pic explained why I couldn't see a seam in the little hub at the center of the wheels on mine, never considered that the whole wheel cover could be removed. Not sure which version I have, unmarked with the 'sound' system in the tender.


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## Pete Thornton (Jan 2, 2008)

yellow_cad said:


> I am not sure how to remove these wheels from the axle


Yellow_cad (don't you have a more friendly name?),
Weren't my instructions above any use? See the green arrow on your pic, below? Insert small screwdriver or pointed implement and push the wheel insert out.










The green arrow is at the side opposite the crankpin so you will see the balance weight between the spokes. This is what it looks like from the back - see the balance weight?










And yes, your gear is cracked and you will need to replace it or the whole gearbox.


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## yellow_cad (Oct 30, 2020)

I believe you are saying to use the balance weight to push the wheel off of the axle so the axle must be square on the ends and a press fit in the wheels. It looks like in the photo that one wheel has a male attachment and the other a female attachment. I'm not sure if this is an allusion and really both wheels have a female attachment. And, finally my last reservation is whether these wheels will go back together and be completely firm and rigid as they are now since this is essential to correct operation.
By the way, if I get the wheels off, I plan to make a shaft collar that I can attach to the gear and anchor to the shaft to stop all slippage of the gear on the shaft since they don't sell the gear and I don't want to buy the complete chassis.


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## Nick Jr (Jan 2, 2008)

If I may, you appear to be very lucky that the crack is only at the bottom of the gear, at this time. If the crack works it's way to the top, the teeth will separate and no longer mesh properly. I don't know if this will work for this case, but years ago when we had a cracked head, would drill a hole at the end of the crack, that would stop it from growing. After that would tap and insert threaded rod and grind off excess. In this case just drilling the hole would do.


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## yellow_cad (Oct 30, 2020)

That's a good point and I could drill that hole parallel to the axle, but it all depends on whether I can successfully remove and later reattach the wheels. I I can't remove the wheels, then I intend to get a split collar shaft with the axle ID and turn into that a shoulder that will grip the entire gear boss on one side and hopefully this will take the strain off of the crack.


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## yellow_cad (Oct 30, 2020)

Sorry, I I can't remove the wheels should read If I can't remove the wheels.


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## Pete Thornton (Jan 2, 2008)

yellow_cad said:


> I believe you are saying to use the balance weight to push the wheel off of the axle


If you look at the photos I posted, especially the ones from the Bachmann website, you will notice the wheel insert is separate from the wheel. *Back in post #11, I said:*


Pete Thornton said:


> In typical Bachmann fashion, they have a screw in the center to hold the wheel onto the axle.


So you pop the wheel insert out of the wheel, and unscrew the center screw. The wheels have a nylon sleeve and the axles have a flat on both sides at the end so the wheels stay quartered correctly (= one wheel at 90 deg from the other.)


yellow_cad said:


> It looks like in the photo that one wheel has a male attachment and the other a female attachment. I'm not sure if this is an allusion and really both wheels have a female attachment.


It's an illusion. Those are the center blind drivers, not the wheels on the drive axle. Take a *close *look at this picture:










It looks to me that you have the (very) old style wiper contacts, shown on George Schreyer's site (you did at least look closely at his pictures, I hope?) Those locos didn't have the thick boss in the center of the wheels that is shown above, but otherwise they are similar.










I'll repeat what I said earlier - you need a new gear or a new chassis. Once they start to crack, the plastic is brittle and will continue to break. Bachmann occasionally sells the chassis 1/2 price, or you should find one on eBay for less than $50.


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## yellow_cad (Oct 30, 2020)

Thanks Pete. I will check for the half price sale. One last question on disassembling the wheels from the shaft. I tried to remove some sort of plug to get to the screws, but it looks to be glued or molded in. Do I need to destroy the material covering the screw (white in color) in order to loosen the screw and take off the wheel? 

Also, this exploded view that I believe is my model doesn't show any screws.


https://www.bachmanntrains.com/home-usa/dwg/dwgs/LS_4-6-0_Metal_Gears.frame_&_wheels.pdf


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## Greg Elmassian (Jan 3, 2008)

re-read and look at the picture in post #11... i think it answers your question


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## yellow_cad (Oct 30, 2020)

OK now it makes sense. When I read it originally, the light bulb didn't come on. I think because the gear part was different I didn't look closely enough at the photo.

I was thinking of making an aluminum gear to replace the cracked one. Does anyone see anything wrong with the final drive gear being aluminum and being driven by a nylon one?


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## Greg Elmassian (Jan 3, 2008)

It's really weird, and has flummoxed many a person, just not real obvious.

Aluminum should be ok, watch the lube, perhaps lube with white lithium, so if you get weird wear on the aluminum it might show up, but as you stated, would be more concerned with wear on the nylon gear.

Greg


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## Pete Thornton (Jan 2, 2008)

yellow_cad said:


> Thanks Pete. I will check for the half price sale. One last question on disassembling the wheels from the shaft. I tried to remove some sort of plug to get to the screws, but it looks to be glued or molded in. Do I need to destroy the material covering the screw (white in color) in order to loosen the screw and take off the wheel?
> 
> Also, this exploded view that I believe is my model doesn't show any screws.
> 
> ...


The blue/black plastic wheel insert is pushed in to the metal wheel and overlays the spokes. The white central boss is part of it and comes out as part of the insert. Just try pushing the plastic insert out from behind.

Bachmann's diagrams aren't always perfect. Try a different one, like the Anniversary locomotive.


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## yellow_cad (Oct 30, 2020)

Thanks for all the help on this. Jim


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## Dick Friedman (Aug 19, 2008)

I had this problem with Bachmann's trolley. The gear cracked. The motor turned, but nothing moved. I printed a gear.


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## Pete Thornton (Jan 2, 2008)

I did get a photo via PM, so in the interests of completion I'll post it here.










The drivers were a much older version, held on entirely by splines, with the wheel insert molded in. The wheel came off with a good pull.


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## Nick Jr (Jan 2, 2008)

Pete, thank you for posting, I was getting curious and wanted to ask. Has he gotten to the Gear fix yet??


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## Pete Thornton (Jan 2, 2008)

Nick Jr said:


> Pete, thank you for posting, I was getting curious and wanted to ask. Has he gotten to the Gear fix yet??


I haven't heard anything since he pulled the wheel off (which was his objective when he started the thread! It only took 2 pages here, as he didn't have a 'modern' 4-6-0 and I didn't get the photo until last week.) I suggested he ask Jerry Yeramian if such a gear was available.


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## Nick Jr (Jan 2, 2008)

Wake this thread for two reasons, yellow_cad, have you made any progress on the fix?? and after many years on the shelf took this one down and before even applying power wanted to check it out to see if my gears had cracked and lube it up. The original grease is more like soap, and very little of it in there. Started to add some and ran out, good excuse for a hobby shop run. This is the one with the antlers under the headlamp. Interesting to note: all of the axles are joined by plastic to insulate the sides from each other, and the wipers appear to pick up on the front and rear drivers, also the pilot wheels.


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## Pete Thornton (Jan 2, 2008)

Nick Jr said:


> all of the axles are joined by plastic to insulate the sides from each other,


Nick, that looks like a later version, with the brass bearings and (I'm guessing) the brass strips on the bottom plate that contact the bearings to collect track power.

I'll repeat what I said earlier - this is the first 4-6-0 that I heard of with a cracked gear. Yours may be fine. The wheels should come off by removing the wheel inserts and unscrewing them, as I noted before.


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## Nick Jr (Jan 2, 2008)

Yes you can see the brass strips that rub on the axles. Don't know when the later version came out, if my memory is correct I had this one when I moved here in 04. As you can see it has no valve detail and the side rods are a very flexible plastic it came as a set with trailing cars. Is there somewhere on the loco or tender that can tell me the date of manufacturer?
EDIT: forgot to mention the gears are fine just cleaned and re-greased. Very smooth runner on rollers.


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## Pete Thornton (Jan 2, 2008)

Nick Jr said:


> Is there somewhere on the loco or tender that can tell me the date of manufacturer?


Well, we arrange them by "generation" or 'gen'. The first was the battery Big Hauler with the plastic wheels. The usual indicator of which gen is the bump under the gear axle. You have the bump so you have a gen5. That's the good one which has few known problems - certainly the gears are fine.

There's the Anniversary version and there's a similar gen6, both with metal gears. There is a new version just been released, but it is mostly a gen6 with a better tender and DCC wiring. Let me scoot over to the Bachmann forum and make sure I got this correct. 
Ah - Loco Bill lost all his database when someone stole his laptop [and backups - he was moving to a new house.]
George Schreyer has a good description:
Big Haulers Tips

Oops - I didn't read the thread all the way down.
Bachmann Forum
Loco Bill has a table in the thread with dates.


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## Nick Jr (Jan 2, 2008)

Pete, thank you, I did see the link to Loco Bill's table on the Bachmann forum. From what was described seems I got this one in the early run of the 5A's as the location I purchased from changed vendors early 2000, and also remembered other incidents that clarified the date for me.


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## Nick Jr (Jan 2, 2008)

A very smooth running loco, enjoy.


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## Matt Vogt (Jan 2, 2008)

Pete Thornton said:


> If you look at the photos I posted, especially the ones from the Bachmann website, you will notice the wheel insert is separate from the wheel. *Back in post #11, I said:*
> 
> So you pop the wheel insert out of the wheel, and unscrew the center screw. The wheels have a nylon sleeve and the axles have a flat on both sides at the end so the wheels stay quartered correctly (= one wheel at 90 deg from the other.)
> 
> ...


Thank you so much Pete for the information! I couldn't figure out how to get the wheels removed, but it was, of course, very simple once I saw how to remove the wheel covers. I bought a gearbox years ago, and one of my 4-6-0 Annies finally decided to shred the gear. I'm wondering if a replacement chassis would be better to have on the shelf for the next one...?


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