Athearn Bluebox SD9 to DCC?


DakotaLove39

DakotaLove39

Always Improvising
Last year I bought a BN SD9 off of Dispatcher812, and I hate to say that for most of that time it's sat in its box.. waiting...

Reecently I finally broke it out and got it running. It's an old growler for sure, my P2K GP38 was dead quiet compared to the old hood. (I think it needs some cleaning and maybe oil for sure, where's the best places to lube?)

The Athearn internal setup is not something I'm used to looking at, and in fact it totally caught me off guard. (Also noticed one of the truck connections was off..)

Is it even possible to wire these older Athearns for DCC, or will this old fighter end up a display model? I'm hoping it can be made digital, as I found out that the local Minneapolis yard has one on hand for whatever needs doing: http://www.rrpicturearchives.net/showPicture.aspx?id=426602
 
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It can be converted to DCC quite easily. Remove the contact strip from the motor. This is the metal strip that connects the motor to the trucks. Now rock the motor side to side until it lifts out of the rubber motor mounts. The drive shafts will slide apart as it's lifted out. Carefully pry the motor mounts up out of the motor well. On the bottom of the motor is a metal strip with two fingers projecting from it. These connect the motor to the locos frame. Flatten these fingers or break them off. Solder a 4" wire to the strip keeping the solder blob as flat as possible. Look in the motor well. In the center is a thin shiny area between the holes the mounts were in. Cut two strips of electrical tape and place them on the shiny area so they cover it but don't block the holes. This will keep the motor from making contact with the frame. Put the motor mounts on the motor then push it down into the well taking care that the commutator is toward the front of the frame. Don't worry about connecting the shafts yet. Now that the motor is in carefully pop the worm housing off the top of the front truck. This can be done by slipping the tip of a flat blade screwdriver under the lip of at the side of the housing and bringing the screwdriver shaft down against the frame using it as a lever to pry the housing up. Do it gently and keep a thumb lightly against the top of the housing. You don't want it to fly off. Also keep your fingers under the wheels or the truck will fall out. Look at how the worm shaft is positioned then carefully lift it out so the gear beneath it is exposed. Place a drop of oil on this gear. Now carefully fit the drive shaft back together then put the worm back in place and put the worm housing back on. Repeat for the rear truck. Have your decoder handy? Solder the black wire to the headlight bracket. Solder the red wire to the contact arm rising from the front truck. Now solder another wire to the front trucks contact arm and run it back to the rear truck and solder it to the contact arm there. Solder the gray wire to the wire you solder to the bottom of the motor earlier. Remember that top contact strip? fit it to the top of the motor then cut of the pieces that project beyond the motor. Now solder the orange wire to the contact strip. Connecting your lights is done the same as in any other hard wire install. The blue wire connects to the + contacts of both the front and rear lights. The white wire connects to the - contact of the front light, the yellow wire connects to the - contact of the rear light. Wrap a piece of electrical tape around eact exposed connection to prevent it shorting out against and metal surface. Now that that is done place the shell back on the frame then turn the loco over. On the bottom of each truck is a long plastic plate. Slip the blade of a small screwdriver under the front of the plate and push it sideways to pop the side of the plate loose then do the same at the rear of the plate. When the plate is loose lift it off to expose the axle gears. Put a small drop of oil on each gear. DO NOT put the oil on the bronze bearings. The axles, bearings and metal sides of the truck make up the pickup system and electricity is conducted from one to the other of them. Most oils are non-conductive and will insulate the axles from the bearings. Use only a conductive lube on the bearings. Now pop the plate back on then repeat the procedure for the rear truck. Now place the loco on your program track and check your installation. If all is well the DCC system will recognize the decoder and you can program it. If not then you have a short somewhere and you must check each connection to find the fault.
 
What brand decoder would you recommend for these old critters? I have a bunch of them, and also Athearn PA/B's, F7's, etc. How about sound decoders?
 
For ease of installation in Athearn blue box loco I would suggest the Digitrax DH123AT or DH163AT. Both use 'no-solder' clips that take the place of the existing clips on Athearn BB locos. These are for motor and light control. They have no sound. To add sound Digitrax has the SFX0416, a mobile sound decoder that can work with any existing DCC decoder.
 
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jeffrey-wimberly said:
For ease of installation in Athearn blue box loco I would suggest the Digitrax DH123AT or DH163AT. Both use 'no-solder' clips that take the place of the existing clips on Athearn BB locos. These are for motor and light control. They have no sound. To add sound Digitrax has the SFX0416, a mobile sound decoder that can work with any existing DCC decoder.
Click to expand...

Thanks! I'll keep those suggestions in mind when I get around to doing such conversions. I presume that similar conversion techniques will work with Athearn "covered wagons".
 
Awesome. Okay. Between your post and a less-intensive visual guide I found, i think I have the DCC installation figured out. My question is though how to protect the wires and chip from the moving components inside the engine? I was thinking I should build some type of cradle or shelf inside the body or something to that extent..
 
Even simpler than that. tape the decoder wires to the top of the motor so the first 1/8" of an inch of the decoder is resting on the rear of the motor and the rest of the decoder hangs over the flywheel. I've done it like that with the HO decoders for years and haven't had one hit the flywheel yet. The decoders I normally use are Z Scale size and I can tuck them into any small space.
 
Okay, that actually answers two questions. I was concerned about the DCC chip baking itself to death or something.

The original engine only comes with one light for the headlight/cab light. While I've got a soldering gun out (Well, not yet, but in the future) and have this thing apart, can the system handle second light for the rear directional, and what would I connect it to? Second part to this is are my death-inducing P2k GP38 number board lights good for replacing the original SD9 headlight?
 
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I have done a few BB's and I have used either Digitrax DH123 or NCE D13SRJ. I favor the NCE because I am starting to add ditch lights and the D13SRJ is the most economical solution for that I have found, but they are larger. Wiring is identical for both. Both support front and rear lights. the blue wire is common positive and the white and yellow wires are for front and rear lights respectively. With the NCE, use violet and green for ditch lights.

-Chris
 
So the front light would be strung from blue wire to white wire, and the rear light would be blue wire to yellow wire?
 
yes.

If using LED's, which I do, then hook blue to two 1k resistors in parallel, connect positive lead of each LED to resistor and then the negative side of each LED to white and yellow wires.
 
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