The Rotax 618 is a 73.8 hp (55 kW) two-stroke, two-cylinder, liquid cooled, gear reduction-drive engine that was formerly manufactured by BRP-Rotax GmbH & Co. KG. It was designed for use on ultralight aircraft.
The 618 features liquid-cooled cylinder heads and cylinders with a rotary valve inlet and an exhaust valve. Cooling is via one or two externally-mounted radiators. Lubrication is by use of pre-mixed fuel and oil at 50:1 or oil injection. The 618 has dual Ducati capacitor discharge ignition systems and is equipped with two piston-type carburetors. It uses a manifold-driven pneumatic fuel pump to provide fuel pressure.
The engine's propeller drive is via a Rotax type C or E style gearbox. The standard engine includes a muffler exhaust system and an intake silencer and filter, with an after muffler also available to further reduce engine noise. The standard starter is an electric starter. An integral alternating current generator produces 12 volts and 200 watts.
The Rotax 618 is no longer in production.
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Type: 2-cylinder, 2-stroke, rotary valve, oil-in-fuel or oil-injected lubrication, dual carburetors, dual ignition
Bore: 76 mm (2.99 in)
Stroke: 68 mm (2.68 in)
Displacement: 617 cc (37.65 cu in)
Dry weight: 59.1 kg 130.4 lb with electric starter, two carburetors, radiator, intake silencer, exhaust system and E gearbox
Valvetrain: rotary inlet valve, exhaust valve
Fuel type: premium unleaded: RON 90 octane or higher leaded or unleaded or AVGAS 100 LL
Oil system: oil-in-fuel (pre-mix) at 50:1
Cooling system: liquid cooled
Power output: 55 kW 73.4 HP SAE @ 6750 RPM
Power-to-weight ratio: 0.56 hp/lb (1.07 kg/kW)
618 2V DCDI
No cylinders: 2
Bore: 76 mm
Stroke: 68 mm
Displacement: 618 cc
Ignition: Electronic Ducati
Reduction: Gear ‘C’ or ‘E’ 2.62-4
Weight: 48.7 kg
Max pwr: 74.8 hp at 6750 rpm
Max torque: 80 at 6500 rpm
Fuel consumption: 340 G/hp/hr
Price 1998: 35 785,00 Fttc