When a partially disassembled engine turned up at a February 2021 auction, it almost immediately caused a buzz in the gas engine collector world. The auction listing’s humble description – “flywheel engine missing parts” – gave no indication of the engine’s rarity. A photo showed little more than a piston and cylinder lying on top of the engine. But serious collectors pegged it as one of only a very few Sorg engines – if not the only Sorg – known to exist.
Today, the engine belongs to Ed Laginess, Carleton, Michigan. Ed was the successful bidder in the February auction. Marv Hedberg, Sauk Rapids, Minnesota, restored the engine for him. A unique design feature – the piston remains stationary, and the cylinder reciprocates – leaves no doubt that the piece is a Sorg Oil-Gas engine.
The Sorg was a shoo-in for a collection that specializes, as Ed’s does, in engines with mechanical oddities. Some 35 years ago, six photos of the engine got more than a few second looks at a 1985 Rice Lake, Wisconsin, show. Ed saw the photos and tried to find the engine’s owner but the engine basically disappeared.
Fast-forward to a 2021 auction, when Ed was the successful bidder, and then skip ahead to mid-June, when the Sorg made its debut at the Coolspring Museum Summer Exposition in Pennsylvania.
“A lot of the people who looked at it at Coolspring think, because of its size, its intricacies and the attention to detail, that it may have been a factory prototype,” Ed says. “It very well could be the only one.”
Mechanically, he says, the engine is like new. “The main connecting rod was never drilled or tapped,” he notes, lending credence to the prototype theory. “But Marv got it purring like a kitten.”
An unusual source of engine information
You wouldn’t figure Marv Hedberg to be a reader of Cosmopolitan magazine. In fairness, his interest is limited to one specific issue dating to 1912. “Back then, Cosmopolitan dealt with everything under the sun,” he explains. “It was primarily a ladies’ magazine. The covers always showed fancy ladies in fancy gowns, but it had lots of other articles.”
The object of Marv’s interest was, incredibly, a six-page article in the May 1912 issue introducing the Sorg Oil-Gas Motor. The first three pages were little more than a sales pitch for stock in the new venture owned by Gas Corliss Co. of Minneapolis. But the final three pages described in detailed (if flowery) text and illustrations the workings of the unique engine.
The article notes that the engine, which was to be run on kerosene, had been in testing for more than 18 months. “We have laid our plans for a large output, and the entire energy of our plant is now being devoted to the immediate production of the more popular sizes of these engines,” noted the builder. Elsewhere in the spread is an announcement that “Five and twelve H.P. sizes are ready. Three and eighteen H.P. will be ready in ninety days.”
Diamond Iron Works of Minneapolis was identified as the builder of the Sorg, which was designed and patented (in 1915) by William A. Sorg, Minneapolis. “Sorg had a couple of patents on a vertical engine of a totally different design, but otherwise, little is known about him,” Marv says. “The factory that built the Sorg was a custom builder for anybody with a design,” Marv says. “If you had a design, they’d make patterns and build it for you.”
In the six-page Cosmopolitan spread, both Gas Corliss and Diamond Iron Works repeatedly stressed their bona fides. “For our responsibilities,” the Diamond Iron Works article asserted, “see Dun’s and Bradstreet’s (two early commercial ratings services that later merged to form Dun & Bradstreet).”
Assessing the damage
By the time Ed Laginess placed the winning bid on the Sorg, the engine was in need of some TLC. “The cylinder had been cracked and brazed, but the bore had never been cleaned up, and it had different rings that were totally unique,” Marv says. “I sleeved it and got different rings and made it run that way.”
The engine’s intake valve assembly, mixer and the slide bars used to guide the cylinder were missing. Marv produced replacement linkage and CNC cut patterns for the slide bars. “We found a little mixer that looks like it fits really well and it runs really well,” he says. “It’s off a Thor outboard motor but the bolt pattern lined right up with holes on the engine.”
Happily, everything fit. “It was an interesting situation,” he says. “There’s .005-inch clearance on everything on that engine. Everything’s got to be in line with no binding. It’s got to be right.” The engine showed little wear; only the valve rocker arm pivots and rollers were stuck. “I’m not sure it had ever been run,” Marv says. “If it was, it wasn’t very much.”
Economical or not, Sorg engine was behind the times
In 1912, an engine designed around a stationary piston and a moving cylinder was a bit of an odd duck. “By then, most of the engine manufacturers had settled on a standard single moving piston and a heavy hopper,” Marv says. “Some had different cooling designs, but that was about it. In 1912, you could buy a Fairbanks & Morse or International engine for less money and it’d be more durable.”
The Sorg has a sideshaft with small flyball governor that would control the throttle on the mixer, but otherwise the cross-slide with the moving cylinder is the engine’s most distinctive feature. “The cross-slide arrangement is more like what the old steam engines had in the late 1800s, where they would guide the rod,” Marv says. “The piston is guided and held straight, rather than the connecting rod going direct into piston to a wrist pin.”
The engine as found had no built-in oiler. On the finished engine, an oiler tree was placed behind the engine’s flywheels. “The original design shown in the Cosmopolitan article includes an oiler on top of a cover over the top of the crankshaft and cylinder,” Marv says, “so it would have had a drip or wipe-type oiler on it.”
The Sorg has a combination cooling system. Water in the head goes back to the piston and exits through an upper brass tube close to the intake valve. The cylinder is air-cooled with fins.
Marv’s best guess is that the engine would be rated at 1 to 1-1/2hp. With a 3-1/2-inch bore and 16-1/2-inch-diameter flywheel, the 125-lb. engine was small, certainly smaller than the 5hp model referenced in the Cosmopolitan article. “You could use it to pump water, or run a gristmill or washing machine, or shell corn,” he says. “It was just a totally different design, maybe intended to get away from everybody else’s patents.”
The Sorg may have been the product of over-engineering. “They may have had some grandiose idea that it’d be more economical to run,” Marv speculates. “Maybe they thought they could pull in just a little bit of really rich fuel into cylinder and fresh air from the back of piston, but there was no extra suction valve on this engine. Evidently the design didn’t work.”
Bolts provide a challenge
As he started cleaning threads on bolts, Marv was surprised to discover that the engine’s bolt threads were totally different from anything considered standard today. “Every bolt on it was 3/8-20 threads,” he says. “Modern threads are 3/8-24 or -16.”
In the early 1900s, there were no formally established standards for bolt threads (such standards were developed in the mid-1920s). “A lot of the bolts on early gas engines have a 1/2-12 thread,” he says. “The modern standard is 1/2-13, and they do not interchange.”
Eventually, he found 3/8-20 nuts in the U.K., and he located a specialty supplier that had the right tap-and-die to use in making studs.
A most unusual engine
During the 2021 auction, the Sorg was said to have been one of a pair long stationed at a hardware store’s workbench. At some point, the hardware business was sold to a cabinet shop owner. One of the two engines went to an engine collector who was a friend of the cabinet shop owner. “He never knew what it was,” Marv says. “And nobody knew what happened to the other engine.”
Marv remains skeptical about the existence of that second Sorg, unless it has already been scrapped. “The piston and cylinder with this engine were somewhat greasy,” he says, “not rusty as shown in original (1985-vintage) photo.”
In short, no one knows how many Sorg engines were built, but Marv knows this much: It’s one of a kind. “I’ve never seen any other engine with a similar design. It’s definitely the most unusual engine I’ve ever had my hands on,” he says. “It was a challenge but it was fun.” FC
Scale model paved the way for a smooth restoration
Fascinated by the unusual engine he first saw in photos in 1985, Marv built a 1/2-scale model of the Sorg some 20 years ago. Working from the original photos, he scaled the model off a 1-inch paint brush shown in one of the pictures.
It was a useful exercise. This year, when he got his hands on the full-size engine, he knew exactly what he was dealing with. “I had it running within a month,” he says. “I totally understood the engine and what it needed.”
To build the scale model, Marv first drew the entire engine in a CAD program, ensuring that everything would fit. “For me, that was fun to do,” he says. He made patterns for main casting, fabricated the base and machined cylinders. “I found flywheels that looked like they would fit, and they did.”
– Leslie C. McManus
For more information: Marv Hedberg, firstname.lastname@example.org.
To see a video of the Sorg running, visit Farm Collector.
Leslie C. McManus is the senior editor of Farm Collector. Contact her at Lmcmanus@ogdenpubs.com.