Choosing the Right Outboard Engine
Outboard engines can often be lifted or tilted so that the delicate underwater parts are not damaged during transportation or when running ashore. In order to find the right outboard engine for your inflatable, dinghy or sailboat there are a number of things you should be aware of:
Classic petrol outboarder or electric?
The first question to ask when buying an outboard motor is whether to go for an electric or classic petrol engine.
Petrol engines are generally more powerful than electric outboard motors. These types of engine are better suited for use in waters with strong currents, or with larger inflatable boats. If you are planning on taking your inflatable boat over long distances, or want to go fast, a petrol engine is the better choice, as it can always be refilled with a fuel can, quickly and easily. In some regions, however, petrol engines are not permitted due to the noise they make, or there could be seasonal restrictions regarding their use that one should be aware of. Be sure to find out what the rules are for the area you are planning on using your engine in before buying one.
Electric motors are outboarders that run on battery power. They have to be charged with electricity from the main supply. Using an electric motor with a smaller inflatable boat up to 2.5 m is a great idea. The motors are quiet, emission-free and do not vibrate as much as petrol engines, so they are particularly suitable for use in areas where petrol engines are prohibited, for example in nature reserves, and because they’re so quiet, this makes them great for fishing. Most electric outboarders do not have a gear box, making them very light and low-maintenance. Electric motors require no oil, and mechanical wear is virtually non-existent. They have good torque even at low speeds. The high torque and superior efficiency of these engines make it difficult to compare them with combustion engines in terms of pure kW or horsepower. Torqeedo claims that the Cruise 2.0 electric outboard with 2,000 watts of input power is the equivalent of a 3,700 watt petrol outboard (5 hp).
Before buying an electric outboard motor, you should consider the distances you want to cover and the duration of use. These factors are obviously limited by the battery power. You should also keep in mind that charging and discharging the battery must be carefully monitored, as it is possible to damage the battery if it is fully discharged or over-charged.
Our SVB experts recommend…
|… a petrol outboard if you:||… an electric outboard if you:|
The manufacturer –
outboarders from Mercury, Suzuki, Honda, Torqeedo or Minn Kota
After you have decided on an electric or classic petrol outboarder, the next choice is the make. Our online shop is packed with petrol engines from Mercury, Suzuki, and Honda, and electric outboarders from Torqeedo and Minn Kota. Many of our customers have their favourite brand that they have sworn by for years. If this is the first time you are purchasing an outboard motor, you should first check the local service network of the individual manufacturers. This is because engines must be serviced every year so that they are covered by the warranty in the event of damage. The service network of the individual manufacturers can be found on the following pages:
Shaft length also depends on the choice of manufacturer. For example, a Honda outboard motor with a short shaft has a different length to a Mercury or Suzuki.
If you have an electric outboard motor, please note that the Minn Kota outboards in our range are not suitable for use in seawater. If you wish to use the motor here, you should always choose a Torqeedo motor. We can order Minn Kota models suitable for seawater on request.
Power and thrust of an outboard engine
In our online shop, the respective power or thrust of each outboard motor is listed in the name of the engine. For example, the SUZUKI DF 2.5 S is a 2.5 hp engine with short shaft and the Honda BF10 LHU a 10 hp engine with long shaft. If you are looking for a suitable motor for use in inflatables, you will find the information "Motorizable up to XY kw / PS" as well as a maximum motor weight on the respective product pages of our inflatable boats. You will find an overview of all our inflatable boats with their maximum motorisation under more information.
The engine power you should choose depends on several factors:
- size and weight of your boat
- the number of people to be carried (weight) and the resulting total weight
- water current
For medium-sized inflatable boats of 2-3 meters, a 5 HP outboard engine is usually enough, if there is little or no current. For large inflatable boats of 4 meters or more, or smaller boats used in areas with strong waves or strong currents, more powerful outboard engines with 5-20 HP should be used.
The power you choose for your outboard motor also depends on whether you have a boat licence or not. In Germany, people aged 16 or over may sail recreational boats up to a length of 15 metres without a licence in inland and lake areas, provided that the nominal power of the engine does not exceed 11.03 kW (15 hp) and that it is not used commercially. The only exception to this is on the Rhine, where international regulations require a licence for a net power of more than 2.68 kW (3.6 PS). In the maritime sector, recreational craft of up to a maximum net power of 3.68 kilowatts (5 hp) may be operated without a recreational craft licence, irrespective of age, i.e. even under the age of 16, as long as it is not for commercial use.
This regulation not only applies to smaller boats with outboard engines, but also to motorboats or sailboats with built-in diesel engines.
Shaft length of outboard engines
Most outboard motors are supplied with different shaft lengths. Short shafts (15") and long shafts (20") are common. In our online shop you can easily identify long or short shaft engines by their title. An L in the title, such as in the Honda BF 10 LHU stands for long shaft, an S in the title, such as in the Honda BF 2.3 SCHU, stands for short shaft. Whether you need an outboard motor with long or short shaft for your rubber dinghy is determined by the height of your boat's transom. The outboard motor must be mounted so that the plate above the propeller (anti-cavitation plate) is a few centimetres below the waterline of the hull. The distance between the engine support on the transom (upper edge of the transom) and the lower edge of the hull must be measured.
You can determine the required shaft length based on the measured length:
- Short shaft motor: approx. 38 cm transom height (inflatable boats up to approx. 3.80 m length)
- Long shaft motor: approx. 50/51 cm transom height (inflatable boats over 3,80 m length)
For all inflatable boats that are in our online shop, an outboard motor with short shaft is perfectly sufficient. You should choose an outboard motor with a long shaft only for our SEATEC GT Sport 410 with fixed hull.
Mounting an outboard motor with a shaft length that is not appropriate to the boat's transom worsens the sailing performance of the boat. The outboard propeller must be completely underwater. If not, the outboard engine will suck in air and it may be damaged. If it is too deep in the water, efficiency, handling and consumption levels will change. In the worst case, it may touch the ground and damage the propeller or underwater part.
Outboard motors with manual or electric start
The final step is to decide on an outboard motor with a manual or electric start. Smaller outboards are often equipped with a manual starter and a steering tiller that swivels the engine on a bracket around its vertical axis to port or starboard. A small tank is usually integrated into the engine housing. In addition, separate outboard tanks can be connected, which are then often equipped with a level indicator and a reserve fuel chamber.
More powerful outboards are available on request with electric starters, usually with chargers for the starter battery and for supplying power to onboard consumers. If you opt for an outboard motor with electric start, you also have the option of choosing a motor with remote control.
When making your choice, you should bear in mind that outboard motors with tiller and manual start are lighter in weight. E-start and remote steering add weight to outboards.
Do SVB outboards have an external tank connection?
Our 2.3, 2.5 and 3.5 hp outboards do not have an external tank connection. Our 4, 5 and 6 hp outboard engines have an external tank connection. But the tank is not included. Our 8 hp outboards have an external tank connection. A tank and matching hose kit are included.
I wish to purchase an outboard motor with remote control, can I get one from SVB?
Yes, on our homepage we also offer a number of outboard motors with remote control, you will find the links below. The remote control box is included with these outboards. Mercury outboards also come with a tilting axle mount. For Honda outboard engines this bracket must be ordered separately. Our Torqeedo outboard motors with remote control are delivered with remote throttle lever, but without connections to the remote control. Other outboards with remote control or matching conversion kits can be ordered on request.
Outboard motor with remote control
Are control cables included with the outboard motors?
No, control cables are not included with the outboard motors and must always be ordered separately.
Are the outboards supplied with engine oil?
Mercury outboard engines are supplied with 1L 10W30 oil. The outboard motor only needs to be replenished on delivery. Honda and Suzuki outboards are delivered without engine oil. The amount of oil required varies from engine to engine and should be specified in the respective operating instructions. If you have any questions, please contact our customer service.
C2 standard control cables are required for Honda outboard engines. These cables are not compatible when using Mercury/Mercruiser and Mariner outboards. C5 cables are used for these models. Please contact our customer service.
Yes, transmission oil is always added when our outboard engines are delivered.
As a rule, today’s outboards are 4-stroke combustion engines with one or two cylinders. Most of the 2-stroke outboards that were common in the past can now only be purchased from second-hand sources. Compared to 2-stroke engines, 4-stroke outboards have their own oil reservoir. They are significantly quieter and smell less intense. Their fuel consumption is also considerably lower. These points make them much more environmentally friendly than 2-stroke engines.