Steyr Marine Diesel Engines

Two years ago, Steyr Daimler Puch was relatively unknown in Australia - at least in the field of marine diesels.

More recently, the Austrian engine manufacturer has made some inroads (Ed: and is even set to power the latest 'designer' launch by Sydney company, Marshall Lord Launches!).

The reason: release of a 212hp, six-cylinder, turbocharged marine diesel engine onto the Australian market that has caught the eye of both recreational and commercial boat owners.

The Steyr display at the 1999 Sanctuary Cove Boat Show created a great deal of interest and subsequently several new installations and repowers are now being carried out.

Steyr saw the need for a compact, lightweight marine diesel engine to match the advances in boat building technology.  So it produced the 236 - weighing a mere 305kg and giving an impressive power-to-weight ratio of 1.44kg/hp.

The engine is incredibly compact, having a length of only 1038mm and width of 651mm.
Steyr has used its unique monoblock construction method in producing the 236, which means the cylinder head and cylinder block are actually one unit.

Revolutionary Design

This revolutionary design, says Steyr, enables better engine block cooling, reduces overall weight, as well as eliminating head cracks and blown head gaskets. 

Each engine also sports an alloy housing, which is constructed to provide a sound absorption enclosure.  There is no direct contact between the power unit and the alloy housing, which allows the engine to run very quietly and vibration free.

Another revolutionary feature of the Steyr diesel is its modulated high-pressure direct-injection system.

The two-stage injection system is self-bleeding and provides 2000 bar pressure.
Diesel knock is non-existent and the unique system means no need for external high-pressure fuel lines.

Electronic Engine Management

Each Steyr marine diesel features electronic engine management that monitors all the engine's vital functions and precisely controls fuel flow for optimum combustion.

The electronic control allows turbocharging with variable turbine geometry, producing an optimised torque curve.

Each engine features an electronic control box, which can be connected directly to a laptop computer while underway, in order to monitor the engine's performance and fuel consumption.

Trade-A-Boat was asked to inspect a recent Steyr repower to a Riviera 34.  The Riviera 34 was previously fitted with twin 165hp Volvos.

The new Steyrs looked almost lonely in the big engine bay as they are actually 200mm shorter and 90mm narrower than their predecessors.

Each Steyr 236 is also reported to be 125kg lighter than the Volvos.

We took advantage of the electronic engine management system and connected a laptop computer to each engine, monitoring actual fuel consumption while underway.

The owner of the Riviera 34 told me he was very happy with the performance of the Steyrs and was already yielding an extra five knots at top speed, as well as considerable fuel saving at cruise.

It should be noted that these improvements quoted are in comparison to the boat as purchased.

We're unable to compare current figures with a boat with 'fresh' 165hp units.

Nonetheless, the owner said low noise, low vibrations and low emissions were all factors that would lead him to recommend the Steyrs.

The owner chose to fit new MerCruiser Bravo II legs at the time of the repower, but the Steyr diesels can be fitted to most existing or new sterndrive units (which make them appealing if repowering or converting from petrol to diesel).

Alternatively, factory adaptors are also available to suit Hurth transmissions, jet units and surface drives.

At the moment the 212hp, six-cylinder turbocharged diesel is the largest in the Steyr marine diesel range.

This restricts the size of planing hull applications to a vessel of about 35ft with twin motors, depending on the weight.

Steyr also manufacture a 163hp, six-cylinder, 2800rpm turbodiesel engine with a 24V dual-alternator system, which was designed primarily for use in large sailing vessels or displacement hulls.

It also has a 144hp, four-cylinder turbodiesel that produces 106kW at 3800rpm.

For more information on Steyr marine diesels, contact McIntyre Equipment, tel +61 7 3390 8111; fax +61 7 3390 8311.