Strange Motor Wiring in a Lionmaster Challenger 6-38091

I'd have to guess that someone thought it was a good idea to lower the torque for the front motor, maybe they were trying to correct a problem with the front power truck climbing out of the rails on curves.  This isn't a factory mod.

I have not seen the engine personally, but the owner says he purchased it on ebay in 2005 from a seller who claimed it was "new", and from all appearances it was new. He also claims the rectifier appears to have been professionally installed, perfectly mounted with a correct looking screw onto the base plate, and that the wiring was professionally done, with the correct colors, and just the right lengths etc. So I don't know what to make of this. I was hoping someone who worked at Lionel during this time frame might chime in and let us know if was done by Lionel, or it absolutely was not. And if it was installed by Lionel, what is it's purpose?

Rod

You got me Rod, the purpose is obviously to reduce the torque to the front motor.  Maybe that was to correct some issue where the front power truck was getting to rambunctious.   The net result of that wiring is to drop the voltage being seen by the front motor by around 1.5 volts vs. what the rear motor sees.

That engine has a very detailed listing of parts on Lionel site, and there is no bridge rectifier shown/listed.  I too believe it was a mod - bypass it and see if see anything odd happen.

I know this is one of the engines motors aren't available - is the motor still the original?

Jim

I looked at the parts listing before I posted previously Jim, that's why I didn't think it was a factory mod.  If it was a factory mod, it was probably done "after the fact" when they discovered whatever problem it's addressing.

@Jim Sandman posted:

That engine has a very detailed listing of parts on Lionel site, and there is no bridge rectifier shown/listed.  I too believe it was a mod - bypass it and see if see anything odd happen.

I know this is one of the engines motors aren't available - is the motor still the original?

Jim

Jim; unless one or both motors was replaced before the current owner bought it, I have to think they are original. And I agree; no bridge rectifier shows up on the parts listing. But neither does a DCDS with a tag YD2 EDP; but there it is. And if it was modded by a previous owner, where did he get the weird DCDS? And why? It just doesn't add up; though I agree with grj that it looks like it is supposed to reduce front motor torque for whatever reason. Interesting mystery!

Rod

The YD2 DCDS definitely exits and it's actually available still to order, where the 691DCDSYU1 it says to use instead isn't.

691DCDSYU1

DCDS / ODYSSEY 1 MOTOR DRIVER / UNIVERSAL

$99.95

Unavailable

Are you sure it is wired the way you show it and that it is not a voltage drop to both motors.  G

Hard to imagine why they'd drop the voltage to both motors like that, but who knows.   I'm still betting they were having some imbalance issues with the motor torque and decided to address it this way.

@GGG posted:

Are you sure it is wired the way you show it and that it is not a voltage drop to both motors.  G

George; the owner described the wiring and I did the Diptrace sketch in the OP based on that, which he verified when I sent it to him. And the owner is very conversant with engines and wiring, having installed several CC-M modules etc. I would say it's correct.

Rod

Interesting Jim that the YD2 is still available. That's a DCDS I had never heard of.

Rod

So what are the labels on the motors?  I guess if one was different spec and someone felt that the voltage needed to be dropped to keep the RPM the same for the same applied voltage, they added the rectifier.  G