# Rotax 618 > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Rotax_618 > Markdown URL: https://mediated.wiki/source/Rotax_618.md > Source: https://en.wikipedia.org/wiki/Rotax_618 > Source revision: 1350187483 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) Austrian two-stroke aircraft engine 618 Type Piston aero-engine National origin Austria Manufacturer Rotax Major applications Murphy Renegade Blue Yonder Merlin The **Rotax 618** is a 73.8 hp (55 kW) [two-stroke](/source/Two-stroke_cycle), two-cylinder, liquid cooled, gear reduction-drive engine that was formerly manufactured by [BRP-Rotax GmbH & Co. KG](/source/Rotax). It was designed for use on [ultralight aircraft](/source/Ultralight_aircraft).[1][2] ## Development 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](/source/Ducati) capacitor discharge ignition systems and is equipped with two piston-type [carburetors](/source/Carburetor). It uses a manifold-driven pneumatic fuel pump to provide fuel pressure.[1] 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](/source/Alternating_current) generator produces 12 volts and 200 watts.[1] The Rotax 618 is no longer in production. ## Applications [Murphy Renegade](/source/Murphy_Renegade) Spirit biplane powered by a Rotax 618 - [Acrolite](/source/Acrolite) - [ARV Griffin](/source/ARV_Griffin) - [Bede BD-5](/source/Bede_BD-5) - [Blue Yonder Merlin](/source/Blue_Yonder_Merlin) - [Earthstar Thunder Gull JT2](/source/Earthstar_Thunder_Gull_JT2) - [Early Bird Jenny](/source/Early_Bird_Jenny) - [Fletcher Hercules](/source/Fletcher_Hercules) - [Joplin Tundra](/source/Joplin_Tundra) - [Kolb Mark III](/source/Kolb_Mark_III) - [Kolb Slingshot](/source/Kolb_Slingshot) - [Laron Wizard](/source/Laron_Wizard) - [Microleve Corsario](/source/Microleve_Corsario) - [Microleve ML 450](/source/Microleve_ML_450) - [M-Squared Breese](/source/M-Squared_Breese) - [Murphy Renegade](/source/Murphy_Renegade) - [Quicksilver GT500](/source/Quicksilver_GT500) - [Rainbow Aerotrike](/source/Rainbow_Aerotrike) - [Sea-Bow International Sea-Bow](/source/Sea-Bow_International_Sea-Bow) - [Titan Tornado](/source/Titan_Tornado) ## Specifications (Rotax 618) ### General characteristics - **Type:** 2-cylinder, 2-stroke, rotary valve, oil-in-fuel or oil-injected lubrication, dual carburetors, dual ignition - **[Bore](/source/Bore_(engine)):** 76 mm (2.99 in) - **[Stroke](/source/Stroke_(engine)):** 68 mm (2.68 in) - **[Displacement](/source/Engine_displacement):** 617 cm³ (37.65 cu in) - **[Dry weight](/source/Dry_weight):** 59.1 [kg](/source/Kilogram) 130.4 [lb](/source/Pound_(mass)) with electric starter, two carburetors, radiator, intake silencer, exhaust system and E gearbox ### Components - **[Valvetrain](/source/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 ### Performance - **Power output:** 55 [kW](/source/Kilowatt) 73.4 HP SAE @ 6750 [RPM](/source/Revolutions_per_minute) - **[Power-to-weight ratio](/source/Power-to-weight_ratio):** 0.56 hp/lb (1.07 kg/kW) ## See also - [Rotax aircraft engines](/source/Rotax#Aircraft_engines) ## References 1. ^ [***a***](#cite_ref-Raisner_1-0) [***b***](#cite_ref-Raisner_1-1) [***c***](#cite_ref-Raisner_1-2) Raisner, William: *LEAF catalog*, pages 6-105. Leading Edge Airfoils, 1995. 1. **[^](#cite_ref-RotaxDataSheet_2-0)** [BRP-Rotax GmbH & Co. KG](/source/Rotax) (n.d.). ["618 UL - 73.8 HP"](http://www.leadingedge-airfoils.com/pdf/618info.pdf) (PDF). Retrieved 7 January 2012. v t e Rotax aircraft engines Two-stroke piston engines 185 275 277 377 447 462 503 532 535 582 618 Four-stroke piston engines 912 914 915 916 --- Adapted from the Wikipedia article [Rotax 618](https://en.wikipedia.org/wiki/Rotax_618) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Rotax_618?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.