Making a dummy engine but having one problem

[dekker]

I have an older Athearn GP38-2 that I have stripped down to nothing but the frame and trucks and when I put it on the track it bogs my powered engines down. It is almost like it is shorting them out. As soon as I take it off the track my powered engines run smooth again. I have two other Athearn engines that I have made into dummies the same exact way and I have never had a problem. What do you think the problem is? Thanks!

 

[portage]

Probably a short as you said. You might experiment with different wheels.

 

[Cjcrescent]

Did you take the trucks apart and remove the gears, or did you just remove the gear at the top of the truck? If you only removed the gear on the top of the truck, you may have a jammed gear inside. It does sound like one or more of the axles are dragging.
Also check to see if one of the axles is seized by corrosion in the bearing or rust on the steel wheels.

If the electrical bar that comes up from the truck is on the opposite side of the other one, there is the problem, you have a direct short across the frame.

 

[dekker]

short

The only gears that are in the trucks are the ones between each wheel. It rolls freely when pushed by hand. The bar from truck to truck has been taken out. I just do not get it. I looked at my other dummy engines that I made and everything is the same as far as wheels trucks and so on but something is making the powered engines short out when I put the dummy unit on the tracks.

 

[Espeefan]

Check each wheelset with a multi-meter and make sure the half axles are not touching each other inside the gear causing a short across the rails.

 

[Railphotog]

If you took the wheels out of the trucks to remove the gears, you may have not placed all of the insulated ends on the same side. Check and see if the are all the same, this will short out the truck(s).

 

[Cjcrescent]

The only gears that are in the trucks are the ones between each wheel. It rolls freely when pushed by hand. The bar from truck to truck has been taken out. I just do not get it. I looked at my other dummy engines that I made and everything is the same as far as wheels trucks and so on but something is making the powered engines short out when I put the dummy unit on the tracks.

Put just the "dummy" on the tracks. Check for a short. If no short then here is the problem. Both locos have metal Kadee couplers I bet, and are facing in opposite directions from each other. The frames of each loco are still picking up power via the trucks. When they are facing the opposite way from each other, the frames are picking up power from opposite sides of the track, and now you have a short!

Solution is simple. #1: Costs money! Get Kadee couplers for the locos in Kadee's #20 series. These are the insulated series I believe, (you can check on Kadees web site), and will not cause this short. #2: Costs nuttin! Switch the trucks on the dummy engine from front to back. This will reverse the pick-up on the dummy engine to the same polarity as the powered one. Good way to confirm take the bodies off of powered and dummy engines, and place the mechanisms on the tracks as you are going to run them. Make sure the electrical pick-ups on all 4 trucks, (that L-shaped piece of steel coming up from the inside of all trucks), are all of the same side, when these locos are coupled, again as they will be when running, back-to-back or elephant style, (front to back). Even though you've removed the gearing on the truck and the motor, from your description, you haven't removed the electrical pick-up on the trucks.

 

[stlgevo51]

For the short, try plastic wheels.

 

[kjd]

Put just the "dummy" on the tracks. Check for a short. If no short then here is the problem. Both locos have metal Kadee couplers I bet, and are facing in opposite directions from each other. The frames of each loco are still picking up power via the trucks. When they are facing the opposite way from each other, the frames are picking up power from opposite sides of the track, and now you have a short!

Solution is simple. #1: Costs money! Get Kadee couplers for the locos in Kadee's #20 series. These are the insulated series I believe, (you can check on Kadees web site), and will not cause this short. #2: Costs nuttin! Switch the trucks on the dummy engine from front to back. This will reverse the pick-up on the dummy engine to the same polarity as the powered one. Good way to confirm take the bodies off of powered and dummy engines, and place the mechanisms on the tracks as you are going to run them. Make sure the electrical pick-ups on all 4 trucks, (that L-shaped piece of steel coming up from the inside of all trucks), are all of the same side, when these locos are coupled, again as they will be when running, back-to-back or elephant style, (front to back). Even though you've removed the gearing on the truck and the motor, from your description, you haven't removed the electrical pick-up on the trucks.

You can also put #5 in its plastic box and mount it on the frame with a screw to avoid shorting between the locomotives.

 

[Cjcrescent]

You can also put #5 in its plastic box and mount it on the frame with a screw to avoid shorting between the locomotives.

I've found to use #5s on a BB loco, the coupler pads have to be filed a lot to get the couplers to match the Kadee gauge.

Here's something even simpler. If the locos are not going to be uncoupled from each other, to change the consist, replace the coupler between the engines with a drawbar made of plastic.