“Gustav,” our venerable 1980-s vintage LGB 0-6-2T, finished an adult beverage run on Sunday and, upon return to the rural community of Dogwallow, froze and made a horrible grinding sound as if he was eating his gears. I will warn you in advance, electric motor theory eludes me.
I opened “Gustav,” found no obvious sign of wear on the worm gears or the axel-mounted helical gears the worm gears drive.
I did electrical connectivity checks, all were OK. Putting test leads to each wheel pairing powered “Gustav” in forward and reverse. Thinking the motor may have just gotten bumped out of its cradle, I reassembled the old fellow, placed him on a test track and…nothing. Just, every so often, that grinding noise. If I removed “Gustav” from the track and powered him via test leads, around went his drive wheels.
There is a possibility minute wear over the years and a slight distortion of the motor shaft is an issue, causing the gears to slip and / or bind. The gear box in which this sits has a yoke on the upper tray that is supposed to hold the motor and shaft in place. There is no indication of warpage in the tray or breakage in the yoke. I am thus guessing this is the motor, but, do DC motors fail like that? Does enough internal resistance build up over the years that eventually, the voltage across the motor won’t turn the thing under load (Load in this case being a several pound locomotive.)?
A new motor is about $70 with shipping, and I can pop it in in 20 minutes. Gearing is about $80 for all three axels (2x geared, 1x ungeared), and, while unpleasant, I have totally stripped this engine down chasing an electrical fault (rotted contact springs and bent internal brass bus bars), so this is still within my skillset. I investigated shipping “Gustav” ($25 each way), and a site advertised “simple” repairs starting at $25.
I’d like to make just one order and be done with it, since shipping is a killer. Is it possible to isolate my issue based on the description above, make an order for one part, and be done with it? If I guess wrong, the shipping on the correct part will almost eat the cost of having a technician do the job in the first place, and I am out the money for the part. On the other hand, if I guess right, the savings are considerable.
Thanks in advance for tips and advice!