Spectrum J class has no torque and little pulling power

[Chris_1522]

I recently picked up a DCC on-board Spectrum N&W J class 4-8-4 at a train show. When I brought it home, it ran very poorly, made a buzzing noise, and had no pulling power. It was suggested that the factory decoder might be of poor quality. I wanted sound anyway, so I bought a Soundtraxx Econami to replace the factory decoder.

The new decoder solved the motor buzz and also with some CV tweaking it runs pretty nice by itself. The issue of pulling power remains. This locomotive has very little and does not slip its drivers, it flat-out stalls. With just a few freight cars behind it, it runs around the layout rather slowly even at throttle setting 99 and when encountering mild grades slows to a crawl or flat out stalls, never slipping the drivers.

If I place it on the track and hold the rear coupler, and throttle it up it just stalls. I've never owned a locomotive that won't slip the drivers.

-It's had two different decoders (factory and Soundtraxx) and it does it with both
-The chassis with the motor removed rolls freely
-The gear train and driving boxes have been lubricated
-The motor spins freely when removed from the chassis
-The motor runs fine when disconnected and ran with a 9 volt battery

I see I can buy a new motor from Bachmann for $20 but I don't want to throw any more good money after bad, if these locomotives are just pulling power duds due to low quality motors or bad gear ratios or something. I plan to call Bachmann CS when they open and see what they recommend.

Has anyone else on the forum gone through this with these locos and if so what was the solution (if there is one)?

[Brewman]

The only time we had trouble with my wife's 611 was when the track voltage was set too low. We ran the locomotive at our club layout for the first time with no problems. Went back another time with three more passenger cars for a total of six and the train would barely move. Acted like the gear was slipping on the motor shaft or something. Brought it home and set up the snap track and Bachmann controller and the train ran fine. Took it back to the club a couple of weeks later and had the same problem. A little investigation and we found someone had set the power supply to N scale = 12 volts input. Switched it back to HO scale = 15 volts and everything was fine. The Bachmann power supplies are 16 volts. This was on a Digitrax system.

Barry

[Chris_1522]

I installed a Northwest Shortline 2032 motor last night. The improvement in torque was remarkable. The factory motor I suspect uses very poor quality magnets, as you could turn the armature by hand and barely feel the magnets "grabbing" the armature. The NWSL motor has a much stronger "feel" as you rotate it by hand.

[brokenrail]

 NWSL motors are great .I am surprised of a dud motor like that in a Spectrum.I have seen many bad or lose connection tabs to the motor brush holder caps that can create a resistance and low power to the motor or just a poor connection somewhere .Rarely the motor unless it was used up with a lot of hours on it.
Johnny