Kemp (Grey Eagle) I-4 or D-4, In-line 4 Engine
The Kemp Machine Works of Muncie, Indiana built several types of air-cooled engines for airplanes, motorcycles, ice boats, and air-drives for boats. Due to its simple design and quantity production, this engine sold for approximately one half the price of its water-cooled competitors, and was lighter, more streamlined, and trouble-free than most of them.
Early models such as this one had concentric valves, which presented a large valve area, but a complicated design. Later models were equipped with conventional valves. All of the 2-, 4-, and 6-cylinder models had automatic intake valves.
A Kemp Model D-4 powered Walter Ralston's 1912 biplane.
Gift of Mrs. L. L. Walker Houston, TX.
Type: Reciprocating, in-line, 4 cylinders; air-cooled, concentric valves; automatic inlet valve
Power rating: 26 kW (35 hp) at 1,150 rpm
Displacement: 4.18 L (255.36 cu in.)
Bore and Stroke: 108 mm (4.25 in.) x 108 mm (4.25 in.)
Weight: 82.2 kg (181 lb)
- Country of Origin
- United States of America
- Kemp Machine Works (Muncie, Indiana)
- PROPULSION-Reciprocating & Rotary
- Length 76 cm (30 in.), 46 cm Height (18 in.), Width 30 cm (12 in.) (Approximate)