Athearn driveshafts on newer motors

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NYSW F45

NYSW F45

Active Member
I need some help. I bought 2 newer style athearn motors with flywheels, driveshafts and worm gears. Also has the dcc/light board attached. The driveshafts I have are similar to dogbone shafts. The old ones I had on my current sd40t-2 are not, they are like ujoints. I need to know if athearn makes different length driveshafts? Im off by like 1/8 of an inch.
 
Yes, there are different length shafts. I'd recommend replacing the worm gear with the matching joint also.
 
Once I cut and spliced a driveline with a piece of K&S tubing to make it longer.
 


jbaakko said:
Yes, there are different length shafts. I'd recommend replacing the worm gear with the matching joint also.
Click to expand...

josh, i replaced the original worm gears that had the ujoints attached to them. I didn't think it would be that easy. The originals were metal and the newer ones are red plastic. Im off from work now for 4 days so i'll have time to play with it. I think i'm just going to cut the shaft flush at the stop sign shaped piece and then trim just a little bit off the shaft then re-glue it.

Once thats done, do you guys recommend me just using double sided tape to attach to the motor or drill out the motor mounts that have lead poured into them and mount the new motor with the supplied mounts? Also this motor has the electrical connectors that go on the older style trucks with the "L" shaped piece. But there is also 1 wire trhat has a square shaped piece of metal with a hole in it. Is this the ground? Do I attach it to the frame or no?
 
I don't think the cross section of the cut shaft will be enough glue surface to hold the hexagonal part on. You could cut it off like you said and center drill the hex part but that requires a lathe or fancy setup to get it done. Like I mentioned before, you could splice it with a piece of K&S or Evergreen tubing. Another thought is that sometimes you can move the cup part on the worm gear shaft to make that part a little longer or shorter. At first I thought it was too short but maybe it is too long?
 
the shaft is to long, buy an 1/8 of an inch if that. I thought about cutting the shaft at the hex part and then drilling a whole in the center and then re-inserting the shaft. Then install it, adjust then glue it. what do you guys think?
 
I think the better alternative would be cutting the shafts in the center, and using a styrene or brass tube to sleeve the shafts back together, as previously posted. Trying to drill a driveshaft without some hi-buck equipment will probably lead to less than perfect alignment, and poor performance.

Rotor
 
ok, got it working. I took the one driveshaft and cut it at the hex piece. The took a #61 bit and drilled out the center. But that bit wasn't large enough. So I took my exact knife and slowly just reemed out the center till the shaft fit in the whole. Slid it in, glued and kazaam! Right sized driveshaft. Now all I gotta do is figure out if I want to double side tape the motor down or drill out the 4 holes in the bottom of the fuel tank and use the mounting taps to hold it down.

But now, what do I do about this straggler wire? It looks like a ground, but do DCC equipped motors get grounded to teh frame?

So now that i have my new drivetrain with DCC/light board installed. All I gotta do is install the sunrise enterprises SP rear light bracket, drill out the holes for the rear headlight, holes for the front lights. Which of course athearn only molded openings, never drilled thru the nose for actual lights to be installed. Find a newer style DB hatch like whats on the new RTR tunnel motors and add cannon & co air tanks and i should be done. Besides painting of course.
 
The wire, not the frame from the motor will connect to the decoder. The wire from the frame will also connect to the decoder.

Rotor
 


Rotorranch said:
The wire, not the frame from the motor will connect to the decoder. The wire from the frame will also connect to the decoder.

Rotor
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there is no wire from the frame. the only wire that was there was from the original motor that i ripped out.
 
NYSW F45 said:
there is no wire from the frame. the only wire that was there was from the original motor that i ripped out.
Click to expand...

NYSW F45 said:
Also this motor has the electrical connectors that go on the older style trucks with the "L" shaped piece. But there is also 1 wire trhat has a square shaped piece of metal with a hole in it. Is this the ground? Do I attach it to the frame or no?
Click to expand...


My previous reply wasn't quite clear as to what I meant. Sorry, I was at work when I posted that, and got busy and didn't really finish the post.

Sounds like your motor is wired for DC. If you wire it as supplied, it won't run on DCC, only DC. If wired as supplied, the wire with the square terminal would attach to the frame with a screw, and the others to the "L" shaped pieces.

For DCC, the motor will require 2 wires from the decoder, one to each brush terminal on the motor. The wires on the motor should already be attached to the brush terminal. You can cut those leaving enough wire to reach the decoder, then solder those to the decoder motor outputs. They will not go to the frame, or the "L" shaped piece on the trucks. You will need to run wires from the "L" shaped pieces to the decoder. You may be able to use the cut off terminals for the connection form the "L" shaped terminals, and from the frame to the decoder.


Rotor
 
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The replacement motor/drivelines/wiring you got came from the basic rtr units, if you follow my suggestions, I'll walk you thru this. I bought about 5 sets of these off ebay myself.:
Since this is on a basic rtr unit, and not the better units, They used a shortcut here and didnt run the wires straight from the truck sideframes. Instead they used the old trucks and a lil creativity. The right side of the truck power is transferred via a clip to the top of the truck, and the left side of the rail is thru the frame via a small tab-like square with a screw in it.
I know what wire your talking about, it's a single wire with a metal tab on it with a hole/screw thru it, correct? if so, it does go to the frame. That is the one single element that hasn't changed with athearn motors and dcc boards. The left side of the rail still connects to the frame via the flat surface on the truck that the frame rides on. And by doing so it "grounds" the frame, ( ground being a dc-only term here). The dcc ready board that sits on top of the motor picks up the "ground" from the frame via the wire with the metal tab. Now this is only in reference to the early dcc-ready loco's that athearn put out. As for the board, it should have 4 sets of pinouts on each end. The pin-out is as follows, with the unit facing away from you:
far left, left side of rail or the frame
middle 2, for the forward light(s)
far right, right side of rail or top of the truck clip

and the bottom of the board is the same, jsut reverse order, but maybe missing the wire going to the left side of the truck.

I saw this in a ACL GP40 I picked up a while back, and even though it wasn't a "RTR" unit, it still had the hex driveline system in it, but with no dcc-ready type board. These units, to make dcc, you have to replace the light boards in.

I hope this helped you.
 
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thanks TB. It helps out greatly.

But why would I have to replace the board if i was to go dcc? the board has the 9 pin plug for a decoder.
 
Well, when I first wrote the reply, it didnt dawn on me that you had the dcc-ready board, until afterwards, hence the edit. But, more than likely, those motors and drivleines were pulled from sd38's, or 50's.:cool:
 
Yeah, that's who I got mine from. Good setup for a C44/Ac4400, just drop right in to replace the old worn out motor or to just repower one. And the lights are included with is a big plus to me.:cool:
What I like is that with 2 solder connections on the main board, you can drop in a nce d13srj decoder, 2 1k resistors and power up ditch lights to function properly. What makes this different than the other thread about soldering points is, that this board actually has the correct solder points for the cheap resistors you can get from radio shack.:cool:
 
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very nice. I can't remember if the dash 9 demo i have has this type of motor/board or not. if not then i'll be getting another one for that engine. the second motor i have no is to repower my old bb fp45.
 


NYSF...I apologize if I confused things here. The way I was reading the posts, I thought you had a seperate pre-wired motor and a board. I didn't realize it was a "pull-out" unit assembly. The pic clarified what you had. My bad. :o

T-breed...Thanks for clarifying the issue.

Sorry for any mis-information I may have supplied, folks. :rolleyes:

Rotor
 
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