Austin Marine Engine (1934)
Austin Thetis Marine Engine

THE AUSTIN THETIS SEVEN H.P. MARINE ENGINE.—The above view reveals the compact proportions and robust design. Note the water pump and hand starting gear mounted forward and the generous build of the reverse gear. Rubber mountings, a detachable head, and pump fuel feed are further features.

The announcement that Austin marine power units are being exhibited in the Marine Section in the Grand Hall annexe at the Olympia Motor Show revives memories of pre-war days when Austin engines were in wide demand for propelling small sea-going and inland water craft. In fact, Maple Leaf IV, which in 1912 won the International Trophy from America was propelled by engines of Austin manufacture.

Thus the re-entry of the Austin concern into the realm of marine engineering is a development of first importance and their wisdom in beginning with marine editions of the famous Austin Seven and Ten-Four power units will be widely commended. The Seven unit for marine work is styled the "Thetis" and although designed specifically for motor boats, or as an auxiliary in sailing vessels, it incorporates all the essential features which have contributed to the universal success of this game little power unit. The cooling water is circulated by a special pump driven from the front end of the cam-shaft, and passes through coils in the oil reservoir to control the temperature of the lubricant. It then circulates through the water-jacketed manifold before being discharged into the exhaust system. A by-pass cock provides a means of controlling the working temperature.

A special hand starting gear and a simple yet robust reverse gear are incorporated. Another special marine feature is the in-corrodible aluminium alloy used for the crank-case. To prevent the engine racing in neutral, and to facilitate manoeuvring, the throttle control is connected to the reversing lever so that the engine idles when the drive is disengaged.

All parts are highly accessible, and the detachable head simplifies decarbonising. Rubber engine mounting damp out vibration. The bore and stroke are 2.2 in. (56 m.m.) by 3 ins. (76 m.m.). Giving a capacity of 45.6 cubic inches (747 c.c.), and developing over 13 b.h.p. at 3,000 r.p.m., this willing little unit should admirably suit marine requirements.

It is being exhibited on the Austin marine stand, No. 182, as a unit ready for installation, as well as completely installed in a i5ft. 6in. yacht's tender with a Birmabright hull.

Austin Triton Marine Engine


THE AUSTIN TRITON TEN H.P. MARINE ENGINE. The magneto, water pump and hand starting gear are mounted forward. Notice also the accessibility of the carburettor and petrol pump. The sturdy and workmanlike proportions of this unit indicate its ability to give dependable service. that the engine idles when the drive is dis-engaged. All parts are highly accessible, and the detachable head simplifies decarbonising. Rubber engine mountings damp out vibration.

The Triton engine is based on the Ten-Four unit of which 50,000 are now giving every satisfaction in service. It develops 21 b.h.p. at 3,000 r.p.m. and the bore and stroke are 2:4995 ins. (63.5. m.m.) by 3.5 ins. (89 m.m.), i giving 68.7 cubic inches (1,125 c.c.) capacity. It has a large three-bearing crankshaft, full pressure lubrication and detachable head.

The marine features are similar to those of the Thetis engine, there being robust hand starting and reverse gears, pump .water-cooling for the sump and manifold, with a by-pass cock for temperature regulation, and inter-connection between the reversing lever and the throttle to control the engine speed when in neutral. Both engines are available with either coil or magneto ignition.

The price of the Thetis ranges from f58 to f65, according to its equipment, the Triton being listed at from £73.50 to £75. A reduction gear is available for either unit at an extra cost of £6.