Convert Bowser DC Loco to DCC

Model Railroader General Discussion (Model Railroader)
1

I am finally converting my Bowser steam locomotives to DCC. I bought the “fiber brush plates” from Bowser and installed them on the DC-71 motors. I think there are some more steps but they don’t give you any further instructions on completing the conversion.

I believe I saw a tutorial at one time that described in detail the steps to convert steam engines from DC to DCC but have not found it yet.

Does anyone out there know where I could find the tutorial?

Thanks, Doc

2

Doc

Its an easy conversion with the 2 wire motors.

Decoder red wire to chassis on loco, Black wire to tender chassis. Orange and Grey wires to motor wires, Blue and white wire for headlight, Yellow and blue for tender back up light or cab light if you have it.

If you have an old 1 wire motor you can either order the brush plate from Bowser or re motor with a can motor. The old DC71 motors were power hogs and you will need a stout decoder that has at least a 2 amp peak rating.

Pete

3

Pete,

Do I have to insulate the motor from the frame?

If so how could it be done and how could I verify it. I have a VOM meter and some experience with circuits.

Thanks, Doc

4

I have not seen a Bowser motor setup but I know one motor terminal connects to the frame in older models. Break that connection. With you ohm meter, you should not see any resistance when you touch a probe to a motor terminal and the frame. Below is some info from the Bowser site.

http://www.bowser-trains.com/hoother/dcc/dcc.htm

Can motor options

http://www.bowser-trains.com/hoother/alliance/alliance.htm

Tony’s decoder suggestions.

http://www.tonystrains.com/download/dec-installation-hout.pdf

Rich

5

Do yourself a huge favor are repower the brute before you install DCC. There are direct conversions available from Accurate Lighting and Helix Humper.

Both are great choices and make for an easy conversion. As well, you can rest in the fact that the current draw is a fraction of what it used to be…not to mention the improvement in loco performance!

David B

6

Not sure but you may need to physically isolate the motor from the frame - it may be getting contact thru the chassis. If so, it’s just a matter of removing the motor and putting down a thin layer of insulating material (like black or clear tape) and putting the motor back. In doing a couple of Mantua engines (which I suspect are set up like Bowser ones) I also got some plastic screws from the LHS to replace the metal ones that hold the motor in place, so they can’t allow power to go thru to the motor.

7

You do NOT need to isolate the entire motor from the frame. If one brush is grounded to the frame (usually just a contact on the right-hand brush holder/spring/mount), un-ground it by bending the contact away from the frame, or slip a piece of wire insulation over the spring where it contacts the top of the brush. Then wire your decoder as described above.

EDIT: To test whether the brushes are grounded to the frame, place one test probe on the frame, and the other on each of the brushes in turn. You should have infinte resistance. If there is zero resistance or close to it, the brush is grounded.

8

Doc

Only the motor brushes have to be isolated from the frame. The motor case or frame will still be in contact with the frame when mounted. I measured the amp draw on my I1s at .978 amp when stalled with a DC71 motor. The current draw on the M1a with a helix humper motor and fly wheel was .652 amp. That is with 13 volt DC on the rails. I will convert these to DCC when I can afford the QSI decoders for them later.

Pete

9

Hey guys,

Thanks for the all the help. I think Tony’s tutorial was the one I remember.

The other key item was checking the resistance between the frame and the “BRUSH” to determine if the motor was isolated. This makes a big difference.

Once I get all of locomotive working on DCC I will look at re-motoring them.

Thanks again, Doc

10

If you’re going to re-motor, I would do it now. No sense soldering all those connections together just to have to un-do them in a while to replace the motor.

11

Pete,

I have installed the brush plate on the old style motor. I now just have to solder the decoder’s red wire to the loco chassis and the black one to the tender chassis? I have them wired to sweepers to pick up from wheels and it’s not working. Thanks…

tom b