# Voltage drops drastically with Bachmann engine



## Reinruss (Sep 7, 2020)

I have a problem. I just finished first layout, less than 100 feet. When I check track voltage using a multimeter on empty track, I get good results (max. of 24 volts) on every section). Then I put my Bachmann Big Hauler loco on it, and the loco doesn’t budge. Voltage on the track drops to less than 2 volts. What is doing this? I suspect wires are crossed in the loco, but I’ve checked and cannot find anything (all black wires go to black, all red wires go to red and nothing seems to be touching). Is motor bad? How do I find the problem? All suggestions are appreciated.


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## Gramps (Feb 28, 2016)

Welcome to the forum. Are you outdoors in G scale, most folks are, so make sure your track and loco wheels are clean. Brass track oxidizes outdoors and has to be cleaned often which is why many G scalers prefer stainless steel. I have been out of G for some time but Bachmann track had a terrible reputation for outdoors.


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## traction fan (Oct 5, 2014)

Reinruss said:


> I have a problem. I just finished first layout, less than 100 feet. When I check track voltage using a multimeter on empty track, I get good results (max. of 24 volts) on every section). Then I put my Bachmann Big Hauler loco on it, and the loco doesn’t budge. Voltage on the track drops to less than 2 volts. What is doing this? I suspect wires are crossed in the loco, but I’ve checked and cannot find anything (all black wires go to black, all red wires go to red and nothing seems to be touching). Is motor bad? How do I find the problem? All suggestions are appreciated.


Reinruss;

A multimeter reading voltage across an empty track is measuring only the voltage available with no load. It can read a good voltage from a nearly dead battery, for example. Your loco needs not only voltage, but current, to run.
I don't understand the reason for 24 volts (DC I hope) I have a Bachmann "Big Hauler" loco that runs just fine on six D-cell batteries, The maximum combined output of those batteries is only 9 volts DC, so why would you need 24 volts? Are you using DCC control, or traditional DC? Even DCC wouldn't have 24 volts on the track, more like 16 volts AC. 

Since you get a 24 volt reading across the empty track, it's not likely that there is a short, or low resistance, across the track, but it should be checked, if only to exclude that as a possible cause. First clean the part of your track where you are going to take meter readings. If the track is old and tarnished then use some fine grit sandpaper to clean off the oxide and get the rail tops shiny. If the track is new, or recently cleaned, then a rag wet with alcohol will handle the cleaning. 

Set your multimeter to its lowest resistance range. Hold one meter lead against each rail.The meter should read infinity, or open. Now switch to the highest resistance scale on your meter and repeat the test. Be sure, in both measurements, that your hands are only on the plastic handle portion of the meter probes and that no part of your body is touching the track. Touching the metal tips of the meter leads, or the track, could give you a false reading. The high resistance range should also read open. If it does then the track is not shorted, though, as mentioned, some or all of it may well have been/still be dirty. 

Now for the locomotive. Lay it upside down and clean a spot on the wheels at each side. Use your meter, set to its lowest resistance scale, to measure the resistance between the right, and left, side driving wheels. It should read a low resistance somewhere around 10-30 ohms, but it should not read zero ohms. That would mean a dead short inside the locomotive.
Speaking of the inside, have you taken the shell off the locomotive, and looked at the inner workings? If it's an old loco, it may have solidified grease on the gears, or there may be a loose wire. Also, if your Bachmann big hauler is the same as mine, you may have damaged the motor by applying 24 volts to a 9 volt motor. Look around inside, and try rotating the motor shaft by hand. You may find the problem.

Good Luck 

Traction Fan 🙂


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## Reinruss (Sep 7, 2020)

Ye


Gramps said:


> Welcome to the forum. Are you outdoors in G scale, most folks are, so make sure your track and loco wheels are clean. Brass track oxidizes outdoors and has to be cleaned often which is why many G scalers prefer stainless steel. I have been out of G for some time but Bachmann track had a terrible reputation for outdoors.


yes, I’m outdoors. I just cleaned the track. I am beginning to agree on Bachmann train quality. I bought the set at the Philadelphia Garden Show in 2001. It stayed in the box until recently. I just don’t understand why merely putting it on the track makes the voltage drop from 24 to less than 2 — without moving the train at all.


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## Reinruss (Sep 7, 2020)

My 


Reinruss said:


> Ye
> 
> yes, I’m outdoors. I just cleaned the track. I am beginning to agree on Bachmann train quality. I bought the set at the Philadelphia Garden Show in 2001. It stayed in the box until recently. I just don’t understand why merely putting it on the track makes the voltage drop from 24 to less than 2 — without moving the train at all.


track is LGB brass.


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## MichaelE (Mar 7, 2018)

You might want to apply track power directly to the motor (if straight DC) and see what those results are. 

Also check to see that the motor turns freely when disconnected from the drive train, and then check the gearbox(es) for each bogie. I don't know the internal arrangement of these locomotives so the procedure might vary.


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## Gramps (Feb 28, 2016)

You have an , at least, 19 year old locomotive that has not been run. That's probably where your problems are. The above posts are good advice.


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## 65446 (Sep 22, 2018)

Bachmann has risen to great heights in the HO and N scale world... I've no knowlege of their G scale.. I only know a bit about LGB from my older brother who had that years ago..I thought they ran great but I didn't care for their out of scale-ness with rail, flanges, and general toyish dimensions and atrocious couplers...
Anyway, it has to be you, something you're doing wrong, not the loco(s)'s. I too would go right to the motor by removing the shell(s) if you must, and applying track power right to the motor leads..If OK, maybe something is jamming the action if I assume the Big Hauler is a steamer... Look for binding somewhere. What about the controller itself ? Are you sure it's the right current for the BH ? If came with the set then maybe it's a cheapy that needs an upgrade...
Good luck... You'll solve it ! M


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## Reinruss (Sep 7, 2020)

telltale said:


> Bachmann has risen to great heights in the HO and N scale world... I've no knowlege of their G scale.. I only know a bit about LGB from my older brother who had that years ago..I thought they ran great but I didn't care for their out of scale-ness with rail, flanges, and general toyish dimensions and atrocious couplers...
> Anyway, it has to be you, something you're doing wrong, not the loco(s)'s. I too would go right to the motor by removing the shell(s) if you must, and applying track power right to the motor leads..If OK, maybe something is jamming the action if I assume the Big Hauler is a steamer... Look for binding somewhere. What about the controller itself ? Are you sure it's the right current for the BH ? If came with the set then maybe it's a cheapy that needs an upgrade...
> Good luck... You'll solve it ! M


Thanks. I am using the Piko 35028 analog r/c controller with Piko 5A transformer. The one that came with it was not robust enough for even a smallish layout. I’ll try the motor check. I appreciate the suggestions. I’ve discovered model railroading requires one to know how to tear everything down, check it along the way and then put it back together without crating new problems worse than the original reason you had to open up the innards in the first place. The cheap plastic parts break if you breathe on them. . I’m learning, but wish I could get the thing to go around the circuit without a problem. Kinda like keeping up an old car. At this point, it frustrating me to the point of writing it off as junk and finding a few thousand bucks to buy a good German train.


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## MichaelE (Mar 7, 2018)

Well, the ABe Allegra 8/12 comes to mind, but even in that scale I believe it is still narrow gauge. You'd have to check it out. I'm not even certain who builds this model. The folks who own this railroad are members of another European forum I belong to.


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## Gramps (Feb 28, 2016)

There were, and maybe still are, G scale forums. Try searches for largescaleonline or mylargescale or largescalecentral . You should get help there. I had used Aristcraft products and was very pleased but they are out of business.


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## Dennis461 (Jan 5, 2018)

Reinruss said:


> ...... At this point, it frustrating me to the point of writing it off as junk and finding a few thousand bucks to buy a good German train.


 Better make sure it is not a power supply or track problem first.

Connect ONE piece of track directly to the power supply and see if your engine will work, that is one piece of track on the kitchen table, not the layout,


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