Modeling Notes: S-Helper Service - 2-8-0

Operator's Manual

(photo © Eric Hopkins)

LocoMatic version (PDF)

DCC version (PDF)

Lights Warning!

Don Thompson warns to not plug DCC decoders into this engine without dealing with the headlights first. The headlights are 5-volt bulbs, and they will blow as soon as the decoder receives power (usually around 12 volts). One option is to consider replacing them with LEDs and a matching resistor. The same applies to sync, smoke, and tender lights, as applicable.

Electrical Pickup

Wheel pickup is provided through the tender's 8 wheels, and through the engine's drivers 1 and 4. Drivers 2 and 3 do not have frame contact. Note that if a short-circuit happens, it is possible for the brass wires behind the wheels to curl away from the back of the wheels due to the heat of the current flow. This will cause the locomotive to stall out from time to time. The solution is to clean the residue from the wires, and re-bend the wires back such that they make contact with the backs of the wheels. If the wires are too far gone, replacements will need to be made (or bought), if they are not in the box.


Don Thompson shared tips how to disassemble and re-assemble this engine. This is an advanced topic, so take care.

You need a 1.6mm wrench to remove the side rods from driver #4 (available from Dave's Twacks & Twains or Hoquat Hobbies). The delrin bottom chassis cover/brake hanger has flat head Phillips screws, and the two delrin injectors are a press fit and need to be detached.

Once removed, you are exposing a flexible printed circuit board that brings power to the headlight, optical detector of the chuff count, smoke unit, and both rail pickups. This unplugs under the cab.

When you lift out driver #4, do not forget that there are two phosphor bronze pick-up pins touching the back of the driver. They are spring-loaded and there are no replacements!

As far as quartering the one driver, should you need to install a new gear, use a carbide scribe and scratch the axle end and driver so that you can line that up as you press the driver back on the axle.

Replacement Gears

Dave Held and Dan Vandermause both report that NWSL has the parts necessary to replace a broken gear in these locomotives. Remove the driver from the engine, and send it to NWSL to have them replace it for you for around $66 (includes postage in late 2016). If you are brave and have the tools and time to do the work yourself, then order the replacement gear (NWSL #2930-6) for $14.95 plus postage. Dan recommends that you order one for each 2-8-0 you have, just in case they develop this problem in the future and NWSL is out of them.

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