Broken drive shaft Bachmann HO?

Hi all I have a used Bachmann GP40 with a drive shafts that keeps slipping off the gear. Not even sure if I’m using the correct terms here. Anyway previously it happened occasionally that I just popped the shell off and slid the shaft back in place with a small screwdriver.

Now it happens constantly. Is this just a replacement part needed?

Heres some pics.

First one to give you an idea of what I’m working with.

Second one is a close up of it slipper off.

Third one is after I slid it back in.

It’s the universal slipping off the worm gear. I small dab of CA should take car of the problem. Be careful to not get any in the ball joint or glue the shaft to the gear housing. Make sure the shaft and universal are free of lube before using the CA.

Mel

My Model Railroad
http://melvineperry.blogspot.com/

Bakersfield, California

I’m beginning to realize that aging is not for wimps.

Can you see if it has any cracks in it? If not, my suggestion would be to clean the ends of the parts in question, put a very small dab of supper glue on the metal worm shaft you have circled and push the universal joint back on to it. If that doesn’t work, then you probably need a new part.

It’s hard to see a tiny crack in a black piece of plastic. I’ve not seen complaints of that part cracking, but Bachmann is known for gears cracking.

I’ve read good things about the Bachmann forum and the they have online parts and parts diagrams.

[quote user=“RR_Mel”]

It’s the universal slipping off the worm gear. I small dab of CA should take car of the problem. Be careful to not get any in the ball joint or glue the shaft to the gear housing. Make sure the shaft and universal are free of lube before using the CA.

Mel

My Model Railroad
http://melvineperry.blogspot.com/

Bakersfield, California

I’m beginning to realize that aging is not for wimps.

I dont see any cracks but will check. So like Mel you’re saying glue this universal part directly in place?

Thanks Henry. Do you mean a user forum on the main bachman site?

this might be the part you need, but I can’t get the larger image to work. Therefore if you have a crack or the glue doesn’t work, ask on the forum

https://tinyurl.com/v3y7z8a

CA is Super Glue. The universal is a universal joint, the black piece hanging down off the shaft. It has to swivel freely on the opposit end that goes on to the shaft, don’t let any excess glue to get into the ball joint.

Keep the glue away from where the shaft goes into the gear housing so that it doesn’t glue the shaft so it can’t turn.

Mel

My Model Railroad
http://melvineperry.blogspot.com/

Bakersfield, California

I’m beginning to realize that agin

Hello All,

Sorry to be the bearer of bad news but glues won’t fix this problem.

I have had several failures like this on Bachmann GPs.

The only real solution is to replace the cracked linkage.

Unfortunately, Bachmann does not sell the individual female part of the linkage. You will need to replace the entire truck gearbox.

To do this go to the Bachmann website and click on the “Parts, Service and Information” link.

From there you can look at a diagram of your particular unit, under “Product Reference”.

Then you can go to the “Order Parts”. Choose from the column on the left “HO Parts”.

Choose the type of locomotive and order the part(s) in question.

Another option would be to get the linkage part(s) from NortWest Short Line. You will need to measure the diameter of the drive shaft of the motor, then order the correct kit.

The above two options will require you to go deep into the guts of the unit. You will definitely need a set of jewelers screwdrivers and possibly the ability to solder if there are any broken wires.

The third option would be to send the unit to Bachmann for repair. The unit does not have to be under warranty for them to do the work.

On the Bachmann website click on the same “Parts, Service and Information” link, then click on the “Service Dept. Info” link.

This will open a window with a “Repair Request” button. Click on that button, set up an account and fill out the form.

You will need a Return Merchandise Authorization(RMA) number, which will be generated for you.

Follow the instructions, print out the label, pack your loco and ship it off.

The repair department will contact you if the item is out of warranty with an estimate for you to approve.

I recently sent in a 0-6-0 steamer in for out of warranty repair. The cost was $45.00, including return shipping.

The entire process

Before I would pay Bachmann $45 I would replace the entire drive line with a $5 NWSL Universal Kit. Most likely a much better repair too.

Mel

My Model Railroad
http://melvineperry.blogspot.com/

Bakersfield, California

I’m beginning to realize that aging is not for wimps.

[quote user=“BigDaddy”[https://tinyurl.com/v3y7z8a]
(https://tinyurl.com/v3y7z8a)
[/quote]

This opened in a new window that I didn’t see. I don’t think it’s what you need. I vote for NWSL

This is the Bachmann part which has way more than you need

https://estore.bachmanntrains.com/index.php?main_page=product_info&cPath=68_185&products_id=7579

Hello All,

The caveat would be if you don’t have the tools or experience to perform the “surgery”.

If the OP doesn’t want to invest in tools and time, $45.00 might not be that much of a hit.

On the other hand, if the OP will be doing future D.I.Y. projects then the initial cost of the tools and the learning curve will be worth the investment.

Just giving the OP some options to his situation.

Hope this helps.

What size shaft and ball is the Bachmann? I have a bunch of Athearn 2mm shaft .156” ball universals I could send him for free! The NWSL balls I stock are 2mm shaft with ⅛” ball.

EDIT:

Another Backmann [:(!][tdn]

Mel

My Mode

Hello All,

If it’s a GP then this is the part from Bachmann…

https://estore.bachmanntrains.com/index.php?main_page=product_info&cPath=68_185&products_id=1306

Hope this helps.

I have repaired many Athearn, Proto 2000 and Bowser locos with this kit:

https://ppw-aline.com/collections/miscellaneous-re-powering-parts/products/12030-universal-joints-coupling-assortment

I only have three Bachmann locos, a pair of EM-1s and an Alco switcher which, so far, have not had any drive-line problems, therefore I can’t guarantee these will fit.

Regards, Ed

I’d buy at least one spare, might not be available later on. I ordered a driver set for a Bachmann GS4 and three weeks later I decided to order a send set and they were no longer available.

Mel

My Model Railroad
http://melvineperry.blogspot.com/

I had the same problem with a Bachmann sharknose diesel. I drilled a #77 hole, perpendicular to the crack, through the universal and the shaft and put a piece of wire, bent over on both ends, through the hole to lock the universal to the shaft.

That method is not practical for the inexperienced though.

There needs to be a better construction design than force fitting plastic pieces on metal shafts. This is a constant problem that affects almost all manufacturers eventually.

Mark Vinski

I have a BLI Hudson, a medium sized steamer. I had a similar problem, only the shaft just slipped inside the coupling. Really, a drop of CA is all it took.

If the OP wants to fix this and is thinking of a replacement drive train, give a cheap drop of glue a try. Sure, it might fail, but if you’re looking at an expensive replacement, try the glue first. It may be fine.

I would also vote for the drop of CA first, as that is the easiest and quickest method of repair for this issue. (Also cheapest. A tube way bigger than needed from the dollar store gets a pack of up to 4, for $1.)

Then, if that failed, I would advance to more options, such as replacing parts.

No experience with replacing this part, but does the replacement also not need glued on? We are still talking about a (relatively) smooth plastic piece press fitting over a (relatively) smooth metal piece, so would not the same issue occur if glue was not used?

I’m basing that off of the fact that a replacement flywheel needs to have glue holding it on, and while the universal isn’t quite the exact same thing, they both still press fit over a smooth metal shaft, and both can hit a pretty high RPM…