Spotlight: O.S. GF40 4-Stroke Gasoline Engine

Ideal for aerobatic or scale aircraft, the O.S. Engine 4-stroke GF40 gasoline engine offers high torque, realistic scale sound, excellent fuel economy, and the superb fit and finish O.S. is famous for. The GF40 has the same firewall mounting system as the GT33, and its choke rod guide has been integrated with the backplate for simplified installations. A Positive Crankcase Ventilation (PCV) system controls blow-by gas and oil waste to keep your model, and the environment, cleaner. Other features include a special Walbro® carburetor and a compact, lightweight ignition module. The GF40 comes with muffler, spark plug and a 2-year limited warranty.
Learn more about the O.S. GF40 Engine by visiting its product page at
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OSMG0800
Displacement: 2.438 cu in (39.96 cc)
Bore: 1.57 in (40 mm)
Stroke: 1.251 in (31.8 mm)
Practical RPM Range: 1,800-9,000
Engine Weight: 42.3 oz (1200 g)
Muffler Weight: 4.0 oz (113 g)
Ignition Module Weight: 3.4 oz (95 g)
Includes: silencer, Walbro carb, ignition module
Recommended Props: 18 x 6W, 18 x 10, 18 x 12, 20 x 8W