I have a Williams DRGW PA diesel (purchased in the late 90’s); the front motor is not working properly and I need to replace it. I have several questions for the forum:
Are all the motors used in Williams diesels the same?
I have upgraded this diesel to ERR TMCC control (including cruise control); should I replace both motors to ensure reasonable synching of the speed?
Can someone suggest a source for purchasing a new motor?
I just checked the Williams by Bachmann online catalog, the motor you’re looking for is catalog number 315-E002, it was interchangeable with the Williams E7 and EP-5, but the bad news is it’s showing “Sold out.” I wouldn’t assume any other Williams motor will fit easily.
Something to keep in mind is that motors with permanent-magnet fields (“can” motors and some American-Flyer motors) try to run at a speed that is proportional to the voltage. When they are wired together in parallel, that is, to the same voltage, multiple motors may fight each other unless they happen to be matched to run at the same speed for the same voltage. Otherwise, one may be doing all the work while the other is trying to slow the locomotive down.
This problem does not occur with traditional series-wound universal motors nor when can motors are wired in series, which is sometimes done to get better speed resolution at a slower operating speed.