Hirth 3701
The Hirth 3701 is an in-line three-cylinder, two-stroke, carburetted aircraft engine, with optional fuel injection, designed for use on ultralight aircraft and small homebuilts.Development
The 3701 was developed as a liquid-cooled and narrower installation alternative to the four-cylinder Hirth F-30 air-cooled engine of.
The 3701 features triple Bing 34 mm slide carburetors or optionally fuel injection. The cylinder walls are electrochemically coated with Nikasil. Standard starting is electric start and recoil start is not available as an option. The reduction drive system available is the G-50 gearbox, with reduction ratios of 2.16:1, 2.29:1, 2.59:1, 3.16:1, or 3.65:1.
The engine runs on a 50:1 pre-mix of unleaded 93 octane auto fuel and oil, or optionally 100:1 oil injection.Variants
;3701 high-torque/low-rpm engine
;3701 high performance engineApplications
