The Sunbeam Dyak was a British inline six-cylinder, water-cooled, twin updraught carburettor engine.
It had an aluminium sump, block and cylinder head, and is an overhead camshaft design with two valves per cylinder. The output was approximately 106 horsepower (79 kW). One was fitted to the first Queensland and Northern Territory Aerial Services (QANTAS) aircraft (an Avro 504K) and was fitted in Australia by the Australian Aircraft & Engineering Co. Ltd. at Mascot, New South Wales. The engine was started by turning a geared crank handle in the cockpit. The diesel-powered Sunbeam Pathan was developed from this engine.
Data from Lumsden
- Type: 6-cylinder, upright, inline engine
- Bore: 4.72 in (120 mm)
- Stroke: 5.12 in (130 mm)
- Displacement: 538.26 cu in (8.8 L)
- Dry weight: 399 lb
- Valvetrain: Overhead camshaft, two valves per cylinder
- Cooling system: Liquid-cooled
- Reduction gear: Direct drive, left-hand tractor
- Comparable engines
- Related lists
- Lumsden, Alec. British Piston Engines and their Aircraft. Marlborough, Wiltshire: Airlife Publishing, 2003. ISBN 1-85310-294-6.