1909 5 HP Otto Special Electric

Wayne Grenning sold most of his collection to buy this gem of an engine.

1909 5 hp Otto

Wayne Grenning's 1909 5 HP Otto Special Electric Lighting engine.

Photo by Wayne Grenning

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In late 1998, a local collector was thinning his collection and making room for future “treasures.”

One of the engines up for grabs was a 1909 5 HP Special Electric Otto. I had seen this engine years prior and immediately knew I needed it. At the time, I asked him to consider me should he ever choose to let it go. The years passed, and at opportune times I would politely remind him of my interest in the Otto.

More than a decade later, I had almost forgotten about the engine.

The deal

One evening, I received a phone call and the voice on the other end said, “The Otto is yours if you are still interested, but I will need an answer within 24 hours.” Well, to make a long story short, I knew what I had to do. We worked out an arrangement where I would have time to sell most of my collection to finance the purchase. The price was fair but at least five times more than I’ve ever paid for an engine. Even so, I never second guessed myself or regretted the decision that fateful evening. I knew in my heart a nicer, more original Otto would probably never cross my path again – this would be my chance.

The engine

Engine no. 10625 has had four owners since the day it left the Otto factory in Philadelphia. The second owner removed it from its original installation and enjoyed it in his collection for years. From talking with area collectors familiar with the engine, I learned that it was originally direct-coupled to a triplex water pump that supplied irrigation for the fairways at an elite country club in Delaware. It was used there for half a century until electric power finally made its service obsolete.

Although a great majority of Special Electric Lighting engines were used for direct- or belt-drive dynamo service, one would occasionally be assigned for water pumping service. In the case of lighting, consistent speed was the most important design consideration. Any speed fluctuation would cause inconsistent output from incandescent bulbs. Surprisingly, a hit-and-miss governor was used on this engine, an almost unheard of speed control for special electric service. It’s possible Otto didn’t see the payback with the time and effort needed to design a throttling governor system for such a small product line.

To compensate for the use of a hit-and-miss governor, this unusual engine was outfitted with two massive 46-inch-by-3-inch flywheels. As if these were not heavy enough for the 4-3/4-inch bore engine, their designers opted to cast the flywheel rims hollow and back fill the cavity with lead, making each weigh almost 750 pounds! The energy stored in these wheels spins the engine through compression for well over two minutes after the fuel is shut off.

Otto also performed a peculiar procedure to the flywheels when assembling their engines. Any run-out or wobble in the flywheels was removed by heavy peening of the spokes. This process was not widely used by engine manufacturers, but it proved effective for correcting flywheel tilt after the gib keys were driven in. It involved taking the round head of a heavy ball-peen hammer and repeatedly hitting the root of the spokes corresponding to the area of the rim that was “out.” For sure, there was an art to performing this procedure, but as expected with such a refined product, the results speak for themselves. The flywheels on this engine run perfectly straight.

Another feature unique to the Electric Lighting engine is the incorporation of a counterbalanced crankshaft. This ensures the smoothest operation possible, canceling out most of the reciprocating forces.

As with all gasoline-fueled Otto engines, the fuel pump can be disconnected from the drive lever and be manually actuated to prime the fuel system. The lever on this particular engine is unlike any other. It has a long arm that extends outward toward the rear of the engine. Once disconnected, it can be manually driven – as you would with the handle of an old well pump. The reason for this configuration is not clear but it may have been to prevent the longer reach around the large diameter flywheels.

On high visibility installations, this flagship model was the engine of choice. Rather than the standard monochrome brown, these engines were highlighted with a paint scheme incorporating yellow-trimmed black panels. Only a small percentage leaving the factory had this appearance. Amazingly, this particular engine spent its whole life under cover. Over the years much of the paint has fallen off of the cylinder; however, some still exists on the crankcase, flywheels and crankguard.

Otto at a glance

As with most American Otto engines, they were outfitted with three cast bronze tags. The largest one (riveted to the water jacket) was rectangular and indicated horsepower, speed and serial number; the second tag, also rectangular, was behind the sideshaft, stating applicable U.S. patents; and finally, the Otto company crest was secured to the crankguard.

Another trademark was the use of “wine glass” shaped lubricators. These unique oilers have raised lettering cast into the glass stating “Lonergans Phil’a Patent Oilers.” Although the body of the lubricator evolved throughout the years, the basic design was used on every Philadelphia-made Otto. American-built Otto engines were extremely well made and engineered. It is obvious the craftsmanship was held to the highest standard, comparable to that of their German counterparts.

They were not mass produced in the true sense, yet most were made in batches of several units. Each engine was laid out and hand fitted. Every significant component of the engine was stamped with a serial number so not to confuse it with another from the same batch, and also to identify it should a replacement part be needed.

The company started making engines in 1877 and was originally named Schleicher, Schumm & Co., a subsidiary of the German Deutz engine corporation. In 1894 it became an independent company, Otto Gas Engine Works. It seems to have been not much more than a name change as the traditional quality and pride from its German upbringing stood fast and continued until the company was bought by Superior around 1920. Throughout the 45-plus years of production, Philadelphia was always its home.

Having collected engines for almost 30 years, I cannot help but appreciate the virtually unmatched mechanical beauty and precision found in these engines. And this unusual 5 HP Otto has been a pleasure to run and has been shown at several shows around the Northeast.

Contact Wayne Grenning at 3678 N. Ridge Road, Lockport, NY 14094 • wgrenning@aol.com

Watch a video of this engine on the Gas Engine Magazine engine video index on YouTube.