# K-27 gear issues?



## Robbie Hanson (Jan 4, 2008)

Fired up the Bachmann K-27 today(about two months old) and under load it's making noises from the gearbox almost exactly like the ones my Connie made just before the gears sheared. Any ideas on why? It does seem to have developed a pretty large bind when the left rod is at bottom.


That and it's riding rather weird and derailing on straights for no reason whatsoever, and has zero traction; it'll start spinning with six or seven AMS cars on level track.


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## blueregal (Jan 3, 2008)

Ok Robbie now you have CURED! me from wanting a K-27, Hah toooooooooo many problems everyday hear more!!! The Regal Careful you'll get you know who's started on a 12 page rampage AGAIN!!!!! The Regal


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## Robbie Hanson (Jan 4, 2008)

Better news! 

The Connie's frame has snapped something and is hanging down and catching on the track. 

How I love Bachmann quality! 

Now I can haul my $1500 in AMS cars with an LGB Mogul....which can't move it.


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## Totalwrecker (Feb 26, 2009)

Check the tires on the drivers if the wheels are two parts castings, ie; plastic center metal rims.


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## Robbie Hanson (Jan 4, 2008)

The K-27 has entirely metal wheels, one piece.


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## paintjockey (Jan 3, 2008)

Is your K one of runs with the counter weights replaced? If not that may be your problem. You also may want to check to be sure all the weights are tight. Mine had a rivet or press fitting, not sure what you call it, that stuck out just enough it was catching on the rod causing a bind.


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## chuck n (Jan 2, 2008)

It sounds as if you may have one of the early k-27s that need a shim between the axle and the Driver. See if you can turn the counterweight on the axle without any other drivers going around. If there is slippage you will be able to rotate it a few degrees (about 5 degrees in each direction). Search this and other forums (January 2008) for some threads that tell how to fix the problem. TOC was the author of the fix. Bachmann will send replacement counterweights, they are easy to install. 


If you bought it new you might be able to get the seller to fix it. I fixed one, it wasn't that difficult, but when I got a second I had the dealer make sure it was fixed before they shipped it. They have worked perfectly for over a year of fairly heavy duty running. 

An LGB mogul should be able to pull some of your AMS cars. Do not over tax the Mogul. If it is over stressed you might strip the idler gears in the motor drive. I have done this by adding weight to the engine and by pulling too many cars.


Chuck


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## Robbie Hanson (Jan 4, 2008)

Original run, replaced counterweights--just bought it new two months ago and did it that night. No issues with it since, until now.


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## StanleyAmes (Jan 3, 2008)

Robbie

Perhaps I can help.

We have several Bachmann K27s on our railroad for use on our long haul runs.

It is really hard to understand the problem you are having so lets start at the basics.

With the power off roll the locomotive on the track. It takes a bit a pressure but it should roll smothly. The headlights should go on and the gearing should be smooth. If there is a problem with the gearing you should be able to determine it with a roll test. If the locomotive runs smooth you likely have no problem with the locomotive. Perhaps the fan noise is what you are hearing.


What Accucraft cars are you trying to pull and what is the vintage of the wheels and trucks?


What power supply are you using?


Normally when the drive wheels on a model locomotive spin, there is no problem with the gearing but a problem that the load is greater then the tractive force of the locomotive.

The early Bachmann K27s did not have their weight ballanced on the drivers. To increase the tractive force you need to add weight to the locomotive and ballancing the weight on the drivers will allow the locomotive to have the greatest tractive force.

Hope that helps a little.

Stan Ames
http://www.tttrains.com/largescale/


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## Robbie Hanson (Jan 4, 2008)

The locomotive does roll freely, nowhere near as freely as an LGB Mogul, but freely. There is a bind felt when rolling that did not exist when I swapped the counterweights. Counterweights are tight, side rods are tight. 

Trying to pull one each of: AMS boxcar, flat, stock, gon, tank, four brand new reefers(acquired Friday). The box and gon are older, the rest of the cars are 2-3 years old other than the new reefers. Brass Accucraft short caboose on the rear, free rolling. 

Using a PH Hobbies 5 amp power supply(older) with an Aristo TE. 

Wheels spin ONLY after the bind--it's as though the loco slows down and then has much more power, enough to overcome the traction of the wheels on the rails. It will sometimes get its footing again when the bind comes around. 

It is indeed an early one and may be unbalanced, but I still don't think my Connie should pull more than a K-27 simply due to weight?


The derailments seem to be occurring only when the engine binds and then suddenly releases, allowing for a sudden burst of power which appears to lift the front axle off the track. 

Photos of the train can be found here: http://s48.photobucket.com/albums/f...chmannK27/


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## chuck n (Jan 2, 2008)

Robbie:

That is a nice looking train. The early AMS cars have truck side frames that bind the axles. Check to see if the wheels on you older cars spin as freely as they do on you newer cars. If they do not call Accucraft and ask for the truck modification kit. They will probably ship it to you at no cost. 


Try running with just the engine. If all goes well then keep adding an additional car until you have a problem. It looks as if you are using 8 foot diameter curves. That is a tight curve for a train that long to pull through. There will be a lot of drag when all of the cars on on the curve. 


If the weight is not evenly distributed as suggested by Stan, gently put some pressure on the cab or smokestack to see if that helps. Then you can add some weight to one end of the engine or the other.


Chuck N


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## jimtyp (Jan 2, 2008)

What diameter curves are you running? 

When you swapped the couterweights are you 100% you put the rods back on properly? 

Is there any wobble in the counterweights? The #3 axle should not have needed replacing. The counterweights on the other axles should now be as tight as the #3 axle. 

Nice looking train


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## Robbie Hanson (Jan 4, 2008)

Running on LGB R3, am looking into Aristo 10' or 11.5' diameter. 

100% sure I put the rods back on properly, I only did one side and one axle at a time to make sure I didn't screw something up. 

The counterweights are secure, slightly less than the #3 axle but MUCH more so than before. 

This is NOT a rod bind. 

I probably should add that the sound it makes is more of a groaning or creaking than a cracking sound--like something's bending and isn't supposed to.


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## steam5 (Jun 22, 2008)

Robbie, 

Is the gowning continuos, short with random intervals or periodic with the motion of the wheels? 

Can you hear where it’s coming from? Does it do it on the straights, corners or all the time? 

Alan


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## jimtyp (Jan 2, 2008)

Could try lubing the main motor gears, that's the only thing I've done besides what you have already. I'm running on tighter curves, 8' diameter and pulling 13 AMS cars, but I have put in BB wheels for all except the caboose (because of electrical pickup). 

I'm thinking you've done all you can and done it right, I'd say next stop is Bachmann, the loco should be under full warranty.


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## Robbie Hanson (Jan 4, 2008)

Lubed the gears and it's getting worse. Binding up 3-4 times per wheel revolution, with a rhythmic metallic hum from the gearbox, a grinding sound. It's now capable of jerking anything behind it off the track and won't run below 20-30 scale mph. 

I did tighten the counterweights too, and they are as tight as I can get them. No side rod binding, though, so it does not appear as though those are the problem.


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## Robbie Hanson (Jan 4, 2008)

I think I may have this solved. 

Opened up the gearbox with the engine flipped, and the two rubber gaskets(O-rings?) were centered over the lip on the side of the gearbox--they appeared to be impeding the drivers. I moved them into the middle of the gearbox and it runs MUCH better. In addition, the axle now moves side-to-side--it did not before. 

More Bachmann quality control issues, i.e. Mallet motor?


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## steam5 (Jun 22, 2008)

Robbie, 

Glad you have solved your problem, its very frustrating when you can’t find an answer. 

Alan


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## SlateCreek (Jan 2, 2008)

I'm not sure, but I seemed to remember something along those lines from the original review of the K-27 .... found it, and got permission to post it here: 

" I tore this unit down far enough to see the main brass axle gear and idler, and to discover that one needs to align the tabs in the plastic axle seals very carefully to get the cover back on the gearbox and still allow the wheels to rotate. 
These seals keep the grease in, and the water out, and the large axles from shorting on the metal gearcase." 


Hope that's helpful. 

Matthew (OV)


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## Robbie Hanson (Jan 4, 2008)

SlateCreek, that worries me; the axle seals were in place, but were SO tight on the axle that it would not slide sideways. They are still on the engine, but next to the brass gear inside the gearbox rather than sealing it. With them how Bachmann shipped it, it will not run correctly(or at least mine won't).


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## steam5 (Jun 22, 2008)

That reminds me, when I opened up my gear box and replaced it back into the chassis the axle went tight like yours, to solve this I backed the screws off slightly until the axel went free. 

Without looking again at my gear box, maybe this could be fixed with a slight shim?


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## StanleyAmes (Jan 3, 2008)

Posted By Robbie Hanson on 14 Jul 2009 09:25 PM 
SlateCreek, that worries me; the axle seals were in place, but were SO tight on the axle that it would not slide sideways. They are still on the engine, but next to the brass gear inside the gearbox rather than sealing it. With them how Bachmann shipped it, it will not run correctly(or at least mine won't). 

Robbie

Glad you found your problem. The seals protect the gearing from water so I would tend to put them back in. I checked mine and one was tighter then I liked. Lubed the axle and the axle and it now moves smothly back and forth.

Stan


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## UK_Pete (May 13, 2009)

*Good news indeed Robbie!*
*I know very well that the Bachmann K27 has issues, but it was this loco that got me interested in largescale in the first place (was just an On30 addict) so I can forgive it almost anything!







*
*I got to go on the footplate of No 464 at the Huckleberry Railroad in Flint-Michigan whilst on holiday from the UK last year and fell in love with the whole D&RG narrow gauge thing then...







*
*I followed this thread with great interest and I am very glad that you have been able to resolve your problem reasonably easily.*
*Cheers from the UK,*
*Pete. 
P.S. Has anyone on MLS visited the "Junction Valley Railroad: (The Largest Quarter-Size Railroad In The world)" in Bridgeport Michigan?
The railroad hobby shop there is a veritable Alladins' cave..... http://www.jvrailroad.com/
*


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## Robbie Hanson (Jan 4, 2008)

Ran the engine for the first time in a week, and it's acquired different issues, and this time you don't even have to load it up to experience this.

Pretty bad vibration, which I can feel through the benchwork. 

Whirring sound coming from the gearbox, along with a light grinding sound which gets worse with time. 

Relubed all the valve gear and the gearbox, didn't help. 

Time to get rid of the engine, or is this %&@*#$ fixable? 

And an FYI for other K-27 owners: If there's a squeaking from the tender, you overtightened the coupler box screw.


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## StanleyAmes (Jan 3, 2008)

Robbie

I now have 4 K27s on our railroad and they are used all the time for hauling the longer trains up the long grades. 3 of our k27s have never been apart, the 4th I have had appart several times testing out some of the reported improvements some of which make things worse rather then better. All 4 have only required periodically lubrication to keep in excellent operation. None of the K27s on our railroad has ecperienced any of the problems you have reported. 

The only sound I get from the locomotive area is the sound of the fan which is on whenever there is power to the locomotive.

My fear is that when you removed the gear box seals you have opened up the gearbox to the elements and any dirt that gets in the gearbox is sure to cause problems.

If you are having problems with the locomotive I would contact Bachmann and if necessary sent it back for repairs.

Stan Ames
http://www.tttrains.com/largescale/


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## Steve Stockham (Jan 2, 2008)

Robbie,
Give Dave Goodson a call at 1-425-823-3507. He's found virtually _all_ of the problems with the K-27 and, more importantly, he has found _fixes_ for them (even though certain people would like to ignore his contributions and would prefer if he would just go away and never be heard from again!) I'm not saying that you shouldn't contact Bachmann but what can it hurt? I had Dave do almost all of the "fixes" before I ever saw my K and it's a wonderful runner! The only thing that wasn't corrected was the gearing ratio but that is another subject and has already been worked to death. Give him a call.


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## Greg Elmassian (Jan 3, 2008)

Hmm... one place you contact knows everything about Bachmann and parts, and fixes, etc..... the other place is Bachmann.... a tough decision? 

Greg


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## Robbie Hanson (Jan 4, 2008)

Stan: 

The engine has been run under five minutes since the seals were moved. No dirt in it, has not been run since that except a few laps around my indoor loop. 

I can try moving them back, but they're still basically stuck on the axle. 

I may call Dave, any good time for him that you know of? 


If I understand correctly, I would have to pay for return shipping if I send it to Bachmann. Pricing on that will probably be upwards of $50 and with college in just over a month, it'll be a huge stretch to dig that up. Oh well, I guess I can see what they say, but I would prefer to have a running engine before I have to abandon it for college...


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## Robbie Hanson (Jan 4, 2008)

Engine is hopefully going back this week. 

Tried to run it yesterday and the gearbox is completely seized up.


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## blueregal (Jan 3, 2008)

Robbie you just hit the "Botchman" lottery, and got um ah well let's say one of they're products that slipped by "quality contol" I would haunt them to death or the retailer you bought it from until it's fixed to your satisfaction! The Regal


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## steam5 (Jun 22, 2008)

Robbie, 

What ever happened to your K-27? Is it well? 

I was reminded of this thread because I was running my K and did something weird, it just made a bit of a grinding noise and the rods stoped turning, but the motor continues to turn until I throttled down, I started it back up again and it ran fine. I stoped it right then as I plan to pull it all apart to put sound in it, I'll investigate it then. 

Alan


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## jfrank (Jan 2, 2008)

Thanks for posting this. You guys have cured me of ever getting one of those things. Long ago I bought one of their connies. It has been back to Bachman to repair a stripped main drive gear. I refused to take that thing apart. They actually replaced all the drivers. The one nagging problem I haven't solved is the motor cutting out when it is overloaded, like more than three cars. lol. I have to turn it off and it resets itself. Mine is battery powered. Is there some kind of overload device on it I can remove. It won't even slip it's drivers.


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## Robbie Hanson (Jan 4, 2008)

Well, good news(that I should have mentioned sooner). 

At the Kansas City show I talked with Allen Pollock from Missouri Train Works. He offered to talk to Bachmann--and two weeks later we drove out to Jefferson City and picked up a NEW K-27--463, second run. 

It runs smoother after only an hour of breakin(I'm in college and have NO time for trains at the moment) than the other one ever did--quieter, pulls more. I'm impressed now; it's nearly as smooth as an MTH Big Boy and smoother than a BBT 4-6-0 drive. 

I'll have to see how it does in terms of long term durability, but so far I suspect it'll be better. 

John: Barry has a new drive for the Connie--I'm going to have one put in mine and will let you know how it is.


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## UK_Pete (May 13, 2009)

That's very good news indeed Robbie![/b]
Hope this one works out for you....[/b]
Pete.[/b]


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## Curmudgeon (Jan 11, 2008)

Unfortunately, motor turning and not the wheels is an issue, or "bug", that has been discovered. 
Preliminary data was submitted to Bachmann, with a request to get back to me if they were interested in full details, UNLESS they already knew about the problem. 

Twice, I sent that. 

NO response. 

Apparently, they are handling everything "in-house", or their consultant is telling them "there is no problem". 

Took me 45 minutes to figure out what was wrong, fix it, and get the unit back into service (during an ops session). 

To have a "weak link" in a system as robust as that one seems to be was beyond my comprehension. 

If your motor spins, but not the drivers, well, Bachmann can help, I suppose. 

And that is as far as I go with this in print. 

I'll wait for the "new helpers" at Bachmann to publish a fix.


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## steam5 (Jun 22, 2008)

Posted By Curmudgeon on 08 Oct 2009 11:50 AM 
Unfortunately, motor turning and not the wheels is an issue, or "bug", that has been discovered. 


Curmudgeon,

What is the bug? Any tips to fix (assuming it can be) the problem would be great!

Thanks
Alan


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## B&RGW (Aug 17, 2012)

I have a first run Bachmann K-27 that I bought used. When I reverse it, it often times seizes. What's wrong? What part(s) do I need to replace?


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## StanleyAmes (Jan 3, 2008)

WIll need a lot more information in order to help out.

The most common cause is that the screws holding the counterweights to the axels have loosened up. Using a smal philips screwdriver, tighten each screw and make a mental note it one was very loose.

If loose then a better long term solution is to use blue loctight on these screws.

A second cause is less common but is posible. A batch on the very first releaser of the K had counterweights that did not fit properly which were immediately replaced. 

To tell if this is an issue you first need to check the tender. If the tender has metal trucks the counterweights are fine. If plastic trucks, then try the following.

Once all the counterweight screws are tight perform the following test.

Hold both counterweights on the #3 driver (the one with the gearbox)

Rotate them, this is the normal freeplay. Now try this to the other counterweights. If the freeplay is more then twice or three times the freeplay of the #3 driver then you need new counterweights.

Hope that helps.

Stan Ames


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