Oil Field Engine News

Holtkamp Oil Field Engines

| March/April 2003

The Oil Field Engine Society recently received correspondence from Paul 'Dan' Vollman, Evansville, Ind., sharing information about his 'Wind Wheel' oil field engine built in Centralia, Ill., by the Holtkamp Electric Service Co.

These were essentially Kohler engines purchased by Holtkamp and modified at their own machine shop for oil field service. The modifications included a flywheel with integrated, cast-in spoke fan (thus the name of the engine, Wind Wheel), a flywheel guard, a mounting base, a Rockford gearbox, a twin-disc clutch, an externally mounted Wico impulse magneto, a gas or gasoline carburetor, and various cylinder bore and piston modifications. Electric starters were offered as an option. Dan's engine is a 1958 4 HP K330COF, single-cylinder model, and these engines were also produced in a two-cylinder version producing 10 HP. The 4 HP and 10 HP models were priced at $550 and $750, respectively. I had the good fortune to speak with Clarence Holtkamp on the phone, and Clarence filled me in on much of the company's history.

Holtkamp History

Clarence's father started in the automobile electric service business around 1920 (thus the name Holtkamp Electric Service Co.). He also sold batteries and eventually went into selling Delco light plants, which used many batteries to operate. The business eventually grew to include Kohler generator sets. As Clarence recalls, after World War II Kohler Company introduced their air-cooled style engine. In February 1957, when the oil fields began to be developed in the Illinois area, Clarence's father got the idea of modifying Kohler engines for oil field use. Between 1957 and 1968, when production of the Holtkamp engines ceased, 516 K660COF two-cylinder 10 HP engines and 783 K330COF single-cylinder 4 HP engines were made. Fifty K385COF models, which were some of the last engines produced, were constructed from Wisconsin parts rather than Kohler parts, and seven engines were built using two-cylinder Lister diesel engines. The 'COF' designation stands for 'Clutch Oil Field.' Clarence said that all of their engines of this type were sold for oil field service. The best years for Wind Wheel engine production were between 1966 and 1968, with 243 engines built during that time.

A circa 1963 ad for Holtkamp engines shows both the 10 HP two-cylinder Model K660COF (left) and the 4 HP single-cylinder Model K330COF (right). The 'COF' designation stood for 'Clutch Oil Field,' a clear reference for its intended duty. Holtkamp Electric Service Co., Centralia, III., built these units from 1957 to 1968.

A Holtkamp 'Wind Wheel' engine at work running an oil pump in the field. Judging by the height of the air cleaner, this appears to be a two-cylinder Model K660COF.

Dan exhibits his Wind Wheel oil field engine along with a 2 HP Fairbanks-Morse on the same cart, and I had the pleasure of meeting him at the White River Valley Antique Association's annual show last September in Elnora, Ind. Not many people looking at this engine realize it did oil field duty, but its large flywheel with integrated fan blades give it away as an oil field engine. Dan showed me a demonstration of the torque the flywheel produces as it coasts through compression cycles once the engine is shut down. This is a good example of how a smaller engine, by means of the torque produced by a large flywheel, can power a big job.