# Bachmann BN 181 trouble



## zefram (Aug 13, 2014)

Hey guys!

I have a Bachmann Burlington Northern GP30 from the early 90s. I hadn't used it for many years, and put it back on the track recently..

It was making a sound like something was making contact with the rail ties.. A plastic sounding clicking noise. I checked everything, even taking off the couplers, but nothing seemed wrong with it. I then found this thread:

http://www.modeltrainforum.com/showthread.php?t=738

And decided to open up the motor to see what's what. I found that one of the gears is missing half a tooth, and has a crack as well.

Could that account for the sound that I heard? What's the likelihood that I will be able to fix the problem? Finding parts might be a problem given my location, but there's a similar model on sale on eBay at the moment... Is that my best bet?

Thanks!

John


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## DonR (Oct 18, 2012)

John 

I have that same Bachmann GP30. When you
took it apart did you find that the chassis is two
cast pieces and that there are no wires, the two
halves conduct all electricity?

If so, we have the same model. Mine makes a 
clicking sound similar to what
you described. I have been unable to trace it
down, but the loco runs so smooth, and is a great
puller that I didn't want to dig into the trucks
further. Some of the plastic fittings are very
brittle from age.

Mine is nothing like what is pictured in your link
however.

I installed a Digitrax decoder made for N gauge
because there is so little space inside.

You might check with Bachmann for a replacement
truck. I did some checking but found nothing listed,
however they may have something lying around.

Don


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## ggnlars (Aug 6, 2013)

If your motor is like the picture, the sound is from cracked idler gears. This is a notorious problem with Bachmann pancake motors. You can try to find old engines with motors with good gears. If you buy 10 engines with 20 gears, you might get four that are not cracked. I do not have another source. For thus reason, I make a lot of dummies. Bachmann sells the whole motor assembly. But I haven't found that they sell the gears.
Larry
check out my blog: www.llxlocomotives.com


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## DonR (Oct 18, 2012)

My motor is an oval can motor with dual brass flywheels, dogbone
drive shafts to worm gear on each truck. Not
the same as pictured.

The clicking in my GP30 seems timed to the RPMs of the motor shaft, not
idler gears. It is as if there were a nub on the motor shaft stricking
something. There is no such thing on it.

It appears Bachmann made several diffrerent
versions. Mine is a Spectrum.

Don


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## zefram (Aug 13, 2014)

DonR said:


> I have that same Bachmann GP30. When you
> took it apart did you find that the chassis is two
> cast pieces and that there are no wires, the two
> halves conduct all electricity?


Nah, mine is nearly what is pictured. Mine has no flywheels or shafts, and is a pancake motor like ggnlars mentioned. I doubt that mine is a spectrum, as I think I mainly have cheap engines that looked cool 20 years ago. 

I actually wired mine, also, to be DCC.. I didn't remember seeing this problem before converting my layout to be DCC.. But maybe I just wasn't careful enough. 

It runs... okay.. with the clicking noise, but I would rather fix that problem as it sounds like something very bad is about to happen if I run it the way that it is. I do have a Life-Like engine with a similar motor, but unfortunately it's thinner than the Bachmann. The gears aren't the right width and don't have the same size hole for the motor to be used instead of the Bachmann's motor.. So the truck on the Life-Like rides very high on the Bachmann (but runs BEAUTIFULLY, even at low speeds).



ggnlars said:


> If your motor is like the picture, the sound is from cracked idler gears. This is a notorious problem with Bachmann pancake motors. You can try to find old engines with motors with good gears. If you buy 10 engines with 20 gears, you might get four that are not cracked. I do not have another source. For thus reason, I make a lot of dummies. Bachmann sells the whole motor assembly. But I haven't found that they sell the gears.


Ugh, I would hate to delegate this model to be a dummy. If nothing else, it has sentimental value to me. I do see that Bachmann has a motor for this kind of engine, but it's currently out of stock. I may just get the model from eBay, especially because I want to experiment with installing better lighting on the model.

Is it possible to re-gear the entire motor? I've seen some gears kind of close to this locally.. But measured in mm instead of fractions of an inch.

Thanks for all the replies so far!! Really appreciated!

John


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## ggnlars (Aug 6, 2013)

The life like clone is does not suffer from the same idler gear problem as the Bachmann unit. They are similar, but I never have tried to switch them. The truck bottom attachments and lengths are different. 
This clicking sound will eventually lead to a failed gear or two. Then the unit won't run. Best to start shopping for a new set of parts. 
As of other parts to regear, I think the issue will be teeth size and number for any other gears. The main gear is on the motor and will not change. 

Don R, early Spectrum units are a pain to work on. The metal frame tends to be the brush holder. The plastic around the motor will get brittle and break away. You could have some debre in the motor causing the clicking sound. It also could be coming from the shafts of the truck gears. If you haven't done it already, you should take the trucks off, clean and lube everything. At that time look at the gear teeth. On might have gotten damaged. When you put it back together, try to run with one truck at a time to see if you can isolate the location of the sound. be carefull that the dreve shaft pieces do not fly away. 
Good luck with these,
Larry
www.llxlocomotives.com


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## DonR (Oct 18, 2012)

Larry

You are right about the disintegrating plastic parts, however
the motor is somewhat sealed so doubt anything in there.
I had the trucks out and did lube their gears. With the
shell off you can still hear the ticking and strangely it seems
to come from both ends. It is nearly imperceptible at
the kind of slow speeds I run so I'll just let it continue
til it grinds to a halt. It's one of the smoothest and best
pulling loco I have.

Don


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## Mr. SP (Jan 7, 2015)

*Bn gp-30 181*

The Bachmann body shell is well done but the paint and lettering is all WRONG!!
It will take a bit of work but I used a Athearn Blue Box GP-35 chassis to repower the Bachman model
It's a kind of cut and fit proceedure but my BN GP-30 has a correct paint job and a very much improved 
drive.
I also replaced the plastic handrails with wire handrails using Athearn stanchions and .015 steel wire. The plastic handrails were used as a pattern to bend the metal handrails


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## Mr. SP (Jan 7, 2015)

*BN GP-30's*

Found a photo of a BN GP30 in Trainpix that shows correct paint and lettering


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