Small outboard motors, limited to 20 hp or so, are readily portable. They are fixed to the boat using clamps, facilitating movement from boat to boat. These motors generally use a start system with a manual pull, and have gearshift controls and throttle mounted on the body, together with a tiller for steering. The smaller of these weigh as little as 10 kilograms (22 lbs), have integrated fuel tanks, and provide enough power to move a small dinghy at about 8 knots (15 km/h; 9.2 mph). This type of motor is mostly used for:
- to propel small boats such as canoes, jon boats, dinghies etc.
- to generate auxiliary propulsion for sailboats,
- for trolling larger boats, as small outboards are generally more effective for such trolling speeds. In this, the motor is generally installed on the transom along the side and connected with the primary outboard to allow helm steering.
An outboard motor engine is self contained. Most of the engine is built of the base engine and a cooling system. Then attached to the engine is a gearbox which then is connected to the propeller via a shaft. Small outboard motors contain all these components, but are designed in a single unit that can be positioned over the stern of a boat and be used immediately. Their sizes are measured in horsepower and most manufacturers produce a range of models from 2 to 300 hp with the larger number reresenting more power. The only external accessory that may be necessary would be a fuel tank (on some models). A large number of small outboard engines feature a fuel tank built-in.
Checklist. Twist-grip tiller throttle – neat labeling and strong construction. Friction control – should be tight to enable the engine to conduct itself. Stop button and kill cord – possibility of the ropes getting enmeshed when you operate the engine. Mounting bracket – should have a wing nut, or at least a captive pin. Screw clamps – look for loops in the screw clamp handles, enabling padlocking to deter from theft. Carrying handle – necessary to transport the engine comfortably. Tank breather and Fuel cap – the cap should to be simple to remove. Gear lever – tiny outboard engines cannot reverse so the lever can select only forward or neutral. Oil sight gauge – this is essential. If oil has leaked out, most sumps just take a mug filled with oil. Fuel tap – check for clean labeling. Tilt mechanism – some models can have positions for multiple tilt.
Electric outboards – These are the future. They are noiseless, environmentally acceptable and compact. But need a heavy battery which will put a limit to your range. Electric outboards in the past were used for trolling – designed to move a heavy boat at a lower speed with its main engine switched off, and often used by American lake fishermen.
Electric engines are environmentally acceptable in use. But when recharging the advantage is lost in case you need to run a generator for hours while recharging the battery. One solution could be shore power. In case you are visiting boatyards frequently, you can charge the batteries when you berth. Or you could get another spare battery and keep it charged.
Another solution is to trickle charge your battery with a splar panel or a wind turbine. A best, you could have two batteries for your small outboard motors – one charging while the other is engaged.
