Generator set goes mobile
One of the benefits of exhibiting gas engines at shows is that you sometimes get leads on more engines. Such was the case with this nice 1937 Fairbanks-Morse Electric Plant. It was given to us by Mark Richardson of Bellingham, Wash., who met us at the Strawberry Festival here in Bellevue, Wash.
The name behind the name
Although Fairbanks-Morse sold this W3S-350 stationary generator set with their nameplate, it was actually made by Onan, which marketed it as the W2C. We found that an Onan instruction manual with schematics can be easily obtained on the Internet, and we used ours extensively while working on the unit.
The Fairbanks-Morse engine is a two-cylinder, upright, 4-cycle gas engine with a centrifugal governor. It is water-cooled with a fan and radiator to dissipate the heat. The generator is a four-pole, air-cooled, revolving armature type. The spark plug wires are shielded, perhaps indicating the unit was for military use.
An ad in Popular Science describes the genset as providing “reliable, economical electrical service anywhere, anytime” and states that it can be ordered in a bewildering variety of options: “AC ranges from 115 to 660 volts, 50, 60, and 180 cycles, and DC ranges from 6 to 4,000 volts; dual voltage types available.” We were fortunate that our unit is dual voltage, providing 115 AC and 15 volts DC. The DC winding serves to charge the battery when the unit is running, and, conversely, the battery can turn over the generator as a starter motor for starting. The unit is provided with a starting crank, but our attempts to use it led to kickbacks and sore arms since there is no provision for retarding the spark.
A feature of this motor-generator is capability for remote starting and stopping, by means of a push button switch, at distances of up to 250 feet away. Because of the remote starting, an automatic choke system is used. We assembled a remote start switch and it works very well. Since there is no conventional starter motor and gearing, the motor cranks over with a quiet whirring sound, which is quite unusual. Also unusual was the adjustment we did to set the governor to give the proper engine RPM, using a frequency meter to monitor the 60-cycle current.
Making it portable
Repairs consisted of removing the gelled motor oil in the crankcase and replacing it with fresh oil, reworking the carburetor and fuel pump, fixing a broken exhaust flange, adding a new gas tank and spark plugs, and replacing a bad switch in the control box.
The bigger project was putting the genset on wheels so we could move it around our museum and load it on trailers for shows. We fabricated a steel-framed cart, including making our own wheels (with bronze bearings), and we decided on tie-rod steering rather than fifth-wheel. This makes for a very stable cart that’s easy to maneuver. We also installed a battery tray and toolbox to finish off the project.
Since the unit had no provision for distributing power, we added an electrical box with a power switch and a fused duplex outlet. At shows we can run lights and fans to demonstrate the utility of the system. Now, the formerly stationary power unit is portable and ready for use!
Contact Michael J. Intlekofer at 4472 119th Ave. S.E., Bellevue, WA 98006 • (425) 641-8471 • email@example.com.