THE STIRLING CYCLE
Century-Old Rider-Ericsson Puts Hot Air to Work
By Leslie C. McDaniel
In its day, the Stirling Cycle engine must have seemed the wave of the future. Dating to 1816, the Stirling design offered a safe, steady source of power. But by the turn of the century, the hot-air engine's days were numbered.
"I'm guessing there were 30,000-40,000 built originally," says collector Steve Gray, who lives in California. "Actually, for a short time, say 1880-1900, they were fairly popular. By 1900, though, gas engines were becoming more popular because they had a lot more horsepower."
Steve's engine collection includes a rare Stirling cycle, Rider-Ericsson hot-air pumping engine dating from about 1895. Designed strictly to pump water, the engine was built to be placed next to a well or a cistern with the pump suction pipe hanging down into the water. During operation, the water the engine is pumping is also used to cool the engine: Before water is discharged from the engine, it passes through a water jacket at the upper end of the cylinder.
Steve's Rider-Ericsson (made in New York; serial number 12704) has a six-inch bore, three-inch stroke, and generates approximately one-eighth to one-quarter horsepower at 100 rpm. The engine weighs about 625 pounds.
Steve was visiting a collector friend of his father's, trading engines, when he saw a curve spoke flywheel in a corner of the garage. He didn't know much about Stirling cycle engines at the time, but he knew enough - even as a novice collector - to know he was looking at something special.
"This was in 1993 or '94, but I knew enough by then to know that a curve spoke flywheel was an early engine, pre-1900," he says. "He told me what it was, and I was familiar with the name, but I'd never seen a full-size, original engine: I'd only seen models."
A deal was struck, and Steve left with the Ericsson: complete, but in pieces.
The first step in restoration was research. "I did manage to find, through Starbolt, a reprint of a book published by Rider-Ericsson. It showed the engine in different sizes," he says. "I spent some time studying that, doing some research. I really wanted to get it back to original. It took a little time."
"Somebody down the line had spray painted it black, just to preserve it," he says. "I had to figure out how to put it together, but it went together pretty well."