Locomotive Mainenance

I spent yesterday doing maintenance of a couple of new HO steam engines that I had bought recently. I took off the locomotive shells and removed the old lube, cleaned the gears, applied new lube and oiled the crossheads and valve gears and side gear. I then tried out the engines to see how well they moved.

When I went to my test track I forgot that I had taken the MRC power unit off of the test track and installed it on my main layout to power the electric motors on a number of switches.

I remembered I still had a few Bachmann’s trainset DC power units in a box, I retrieved one in and hooked up to my test track.

I then placed on of the new engines on the test track to see how it ran, the first locomotive would barely crawl. I thought oh well the engine is 35 years old, another candidate for either new magnets or a replacement can motor,.

I then tried the second locomotive, and it too would hardly crawl, well another candicate for magnets or a can motor, I then tried the third motor and it too would hardly crawl.

I thought I should give the test track another look and went over to my layout and grabed a Bachmann DCC engine with sound, the new mogul, The Bachmann 2-6-0 ran great, the sound was fine.

I then remembered I had another MRC DC power unit in my misc box, I hooked the MRC unit to the test track, and placed the first locomotive that I had initially tried. It ran great, same with the second and third locomotives.

I then realized at how little power the Bachmann DC power unit had in comparison to the MRC units. Does anyone know the rating of the Bachmann’s trainset power source?

Well, a lesson learned, it turned out that the three engines I had recently purchased did not need to be remotored at all. The locomotives were old brass engines with the open frame motor.

I don’t know about the newest ones, but the old Bachmann black power packs with the red two-way handle could only handle about a half amp, and would get pretty warm if I tried using an engine needing more than that. They didn’t have a nice linear control either. They’d start at about 3 volts and jump about a volt and a half at a time until they got up to around 16 volts. The rated current and all was molded directly into the plastic.

Those little train set bricks are rated seven VA (watts) - barely over 1/2 amp at full DC voltage.

Now you why mine have been relegated to structure lighting duties. My bigger locos have two of those old juice-hog open frame motors…

Chuck (Modeling Central Japan in September, 1964)