Steam Dynamo Spins After 54 Years

"The Sunbeam dynamo lit a light bulb for the first time in 54 years," said Keith Berry, El Dorado Western Railway Foundation vice-president.

It last produced electricity in April 1953 when the Diamond & Caldor Railway ceased operation.

This morning chief mechanical officer Doug Youngberg connected the air hose to the steam intake and spun the Pelton wheel shaft. He measured output at 21 volts. Doug believes once the generator is connected to a steam line, output will reach the 37 volts these units produced while in operation.

Lead machinist Sam Thompson said the unit reached 1,800 revolutions per minutes during this morning's test. Once connected to steam, the shaft will turn at the higher 2,400 RPM, according to Doug.

Replacing the pitted Pelton wheel presented the greatest challenge to the dynamo team. Water had pooled inside the housing and pitted the wheel.

The locomotive was displayed in an unsheltered location for 40 years at the El Dorado County Fairgrounds.

"We had little hope of finding a replacement Pelton wheel, let alone finding a new one," said Keith.

An opportunity came last fall when the two located a decades-old replacement wheel at Backshop Enterprises, Colorado company that specializes in the repair and replacement of steam locomotive appliances.

Doug and Keith rebuilt the dynamo in Doug's machine shop on Tuesday evenings over the past 14 months.

The steam-powered turbo-generator will soon resume its rightful position behind the smoke stack on the Diamond & Caldor No. 4 Shay locomotive in Placerville, California.