Chapter 2: Operating a Motor Boat
The outboard motor is a spark ignition engine. Fuel from the fuel tank enters the carburetor where it mixes with air in a given proportion. From the carburetor, the gas mixture enters the cylinder. In the cylinder, a spark plug emits a spark that ignites the mixture, triggering an explosion that drives the piston. This sets in motion a crankshaft (or drive shaft) linked to the piston by a connecting rod. Successive explosions in the cylinder cause the crankshaft to turn and a gear assembly activates the propeller.
The internal temperature of a spark ignition engine is over 3200 Celsius (4000 F). Therefore, the motor must be cooled. Outboard motors are cooled by water.
While the motor is running, water is drawn in through openings located at the base of the motor (see Figure 2.1, no. 14) under the anti-cavitation plate. Water flows around the cylinders before being flushed out into the surrounding body of water through a cooling system control jet. It exits through an orifice located near the cylinder head (see Figure 2.1, no. 1).
Most outboard motors are two-stroke engines; four-stroke engines also exist.
Two- and four-stroke engines differ in the way that lubricating oil enters the cylinders. In a two- stroke engine, oil is added to fuel
in the tank itself (manufacturers specify how much oil to add to the fuel). However, some two-stroke outboard engines have two tanks:
one for gas and another for oil. The oil and gas mix automatically before reaching the cylinders. In a four- stroke engine, oil
is added through a separate opening located near the drive shaft. Too little oil can cause the metal to overheat and damage the motor.
Figure 2.1 — Typical Outboard Motor
- Water pump indicator
- Drive selector or gear selector
- Starter cord
- Emergency stop/tension control
- Emergency stop cord
- Fastening clamp
- Motor tilt control
- Drift corrector/anti-corrosion anode
- Water outlet
- Oil indicator (emptying and filling)
- Water intake device
- Fuel exhaust
- Lift lever
Trouble-Shooting and Maintenance
The engines operating instructions usually provide information and advice on trouble-shooting, minor repairs and maintenance.
To prevent breakdowns, boaters should make a habit of staying alert to signs of motor wear and tear. Similarly, it is advisable to keep spare parts in the tool box and learn to perform basic repairs.
Follow these safety rules when performing repairs:
- Tie back long hair.
- Use the proper tools.
- Remember that even a small motor can give off a major electrical discharge.
- Disconnect the fuel line and spark plug cables.
- Avoid operating the motor in an enclosed area.
- Read the operating instructions before starting the motor.
The repair kit should be air-tight and contain:
- One funnel with filter
- One knife
- Pliers (long-nose and standard)
- Flat and star (Phillips) screwdrivers
- One feeler gauge for spark plugs
- One spark-plug key
- One container of penetrating oil
- Cotter pins and one shear pin
- Spare fuses 3 Disposable cloths
- Monkey wrench (for motor bolts)
- A roll of electrical adhesive tape
- Spare spark plugs
- One starter rope
IT IS EXTREMELY IMPORTANT TO MAINTAIN YOUR VESSEL IN GOOD WORKING ORDER TO AVOID MECHANICAL BREAKDOWNS.
|Motor won't start
- Fuel tank is empty
- Supply line is disconnected
- Throttle not in Start position
- Loose spark plug
- Selector not in Neutral
|Motor starts but not easily
- Gas level too low
- Air inlet of tank is closed
- Fuel line is bent
- Primer bulb not pressed enough (should be firm)
- Choke valve not operating properly
- Fuel contaminated by water or impurities
- Loose spark plug wire
- Spark plug dirty or improper spark gap
- Engine requires a tune up
|Motor running in fits and starts
- Water or impurities in fuel
- Idle mixture adjusting needle of carburetor requires adjustment
- Spark plugs are defective (see above problem)
|Propeller not turning
- Debris caught in propeller
- Selector not in drive
- Shear pin broken
- Fastening clamps are not properly tightened.
- The propeller is unbalanced.
|Motor suddenly stops
- Fuel tank is empty
- No oil in fuel (two-stroke engine)
- Loose spark plug
- Cooling water intakes obstructed or the water pump defective
- Do not use tainted oil
- Keep clean and dry
- Mix proper proportion of oil and fuel.
- Ensure that fuel is free of humidity
- Check condition of hose (cracks, poor connections)
- Check condition of wires (cracks, slack, corrosion)
- Clean and correct spark plug gap; change as required
- Look for signs of spark plug fouling and humidity
- Maintain motor in good condition
- Clean spark plugs and correct spark plug gap as required.
- Protect interior of cylinders with rust-proofing
- Blow out cylinders
- Lubricate all moving parts
- Empty oil pan and refill with new gear oil
- Repeat after every 100 hours of operation or at least once per season
- Empty oil pan and refill with new gear oil
- Ensure that openings are free of plant material
- Desalt certain models in fresh water after salt water use
- Desalt in fresh water
- Drain water completely by activating starter cord after disconnecting spark plugs
- Sand or file cracked surfaces
- Check condition regularly
- Check whether repairs are required
- Clean and touch-up paint as required
- If motor is used in saltwater, repaint with rust-resistant, anti-mildew paint.
- Treat with zinc pain
- Clean and touch-up paint as required
Be aware of the Small Vessel Regulations pertaining to engine power and load capacity.
As a boat owner or operator you should know that the "recommended gross load capacity" that can be safely carried in the hull concerned:
- Includes the total weight of persons, equipment, stores, fuel, motor assembly and steering controls
- Is indicated with the "equivalent number of adult persons"
- Is indicated on a Capacity Plate which, if fitted, is permanently attached to the pleasure craft
The capacity plate also indicates the "recommended safe limits of engine power" for the hull concerned. This calculation is based on the recommended gross load capacity.
Motor Boat Operations
When mixed with air, gasoline evaporates quickly. Therefore, use caution when fueling a boat. Because gasoline fumes are heavier than air, they can accumulate in the hold, i.e., in the bottom of the boat. The following procedure is used for fueling:
- Moor the craft.
- Do not smoke in fueling area.
- Shut down all engines.
- Ensure that all persons not involved in fueling the craft are ashore.
- Disconnect the fuel line and move portable fuel tank ashore.
- Place fire extinguisher within easy reach.
- While fueling, ground nozzle against filler pipe to prevent the build up of static electricity.
- Avoid over filling the tank or splashing fuel.
- Close the fuel tank and clean up spillage.
- Mix the oil and fuel in the tank, adding one and then the other (according to the manufacturer's recommended ratio)
- Replace the tank in the vessel and reconnect the fuel line; the tank should be securely fastened in the vessel, as far from the motor as possible.
- Press the primer bulb to begin mixing air with the fuel.
- Operate the engine compartment blower for at least 4 minutes immediately before starting up the gasoline engine.
The fuel tank should be kept away from sparks and heat and stowed in a well-ventilated location. Always store fuel in a clearly marked fuel container. Fuel tanks are red or orange for safety reasons. Other colours must not be used.
Motor Installation and Adjustments
Before installing the motor, ensure that the fastening clamps (see figure 2.1, no. 8) are open to maximum and that the motor is attached to
a safety rope or chain. If the boat is in shallow water, tilt the motor to prevent the propeller from scraping the bottom. At the
dock, ensure that the boat is properly moored; however, mooring lines must provide enough slack to allow for the effects of added weight. Place
the motor on the dock with the top section toward the boat. Check again that the clamps are open. Using the handles, lift the motor and
set it in place on the stern plate; tighten the clamps and fasten the rope or chain to the boat.
Loading the Boat
Load displacement and water movement in the hold are two factors that affect the boat's stability. Therefore, the load must be secured (tied down) near the hold with ropes, and the hold kept dry. After securing the load, also check the trim of the boat.
Adjusting the Trim
An outboard motor boat is operated and maneuvered as if the hull were moving parallel to the water. Passengers and materials must be placed to evenly distribute the load along the length and width of the boat.
Poor: Too much weight in front
Poor: Too much weight in back
Correct: Load is evenly distributed and ensures optimal performance
One common mistake is to overload an outboard boat. The recommended load capacity is shown on the Capacity Plate issued by the Department of Transport. Never exceed the specified load.
Steering System Tension
The tension of the steering system is adjusted at its pivot point by a screw or bolt called a copilot. It must be tightened just enough
to prevent the boat from changing direction when the operator takes his/her hand off the throttle bar. The tilt of the motor (see Figure 2.1,
no. 9) must be adjusted so that the drive shaft is at a right angle to the surface of the water when the motor is running at full speed. If
the motor leans too far out, the stern of the boat will sink and the bow will tend to tap the water. On the other hand, the bow will tend
to plough the water if the motor is tilted too far in. Trials on the water will show the best tilt in relation to the load.
Motor too close to waterline; vessel will nose dive.
Motor too far from waterline; vessel will tend to tap surface.
Motor is at a right angle to the water surface; operation should be smooth if the vessel was properly loaded.
Lift Lever (figure 2.1, no. 16)
This important device is found on most outboard motors and serves to hold the motor upright against the stern plate. Since the clamp keeps
the motor in the water when the boat is in reverse, it should normally be engaged. As a general rule, the clamp automatically disengages
if the motor strikes an underwater object.
Starting the motor
- Connect the fuel tank to the motor (if the tank cap has an air intake, make sure it is open) and press primer bulb until you feel resistance;
- Take care to remove any debris from the propeller (see figure 2.1, no. 12) and the cooling water intake (see figure 2.1, no. 14);
- Lock the motor tilt lever (see figure 2.1, no. 9) in the RUN position, and the lift lever (see figure 2.1, no. 16) in the LOCK position;
- Ensure that the drive selector (figure 2.1, no. 2) (also called a gear selector) is in Neutral;
- Set the throttle to START (see figure 2.1, no. 5) and use the choke as required (see figure 2.1, no. 3);
- In a sitting or crouched position, tug the starter cord (see Figure 2.1, no. 4) until you feel resistance, then pull firmly in a single stroke. Remain seated to start the motor;
- Check that the control jet (figure 2.1, no. 1) from the cooling system is flowing properly;
- Once the motor is running well, adjust the choke.
- Cast off moorings.
- Shove off in the desired direction.
- Set the throttle to the Shift position;
- Set the drive selector to Forward and adjust the choke and increase the throttle setting.
- With the drive selector at Forward ... slow the throttle back to the Shift position.
- Set the drive selector to Neutral.
- Push the stop button (see figure 2.1, no. 6) (if there is no stop button, pull on the choke).
- On reaching the shore, tilt the motor out of the water to avoid damaging the propeller
The operator must sit to the right of outboard motors that have a steering bar connected directly to the motor.
To change the direction of an outboard boat you must change the position of the motors propeller.
If the bar is pulled to the right, the bow of the boat will turn left, and if the bar is pulled to the left, the bow of the boat will turn right.
With practice, boat operators will soon learn to act quickly and correctly.
When maneuvering in reverse, the lift lock mechanism must be engaged to prevent the motor from tipping. Obstacles must be avoided with great care since the motor is no longer protected from collision.
Reversing is much more complicated than forward maneuvering, and therefore requires extra alertness.
Leaving the Dock
Occupants must enter the boat when the front and rear mooring lines are still fastened to the dock. One person steadies the vessel while the others board by stepping into the bottom of the boat and keeping their bodies as low as possible.
Follow the reverse procedure to get out of a boat.
To leave a dock in a motor boat demands some forethought. If other boats are nearby, the throttle bar (gas control handle) can be moved in the direction of the dock and the boat backed out in reverse. If the wind is blowing from the dock, greater force is required to clear the dock and avoid colliding with other boats.
The boat pulls away from the dock in reverse (throttle bar turned toward the dock). Once the boat is fully clear, it can head out in Forward provided the way is unobstructed.
To land a boat, approach the dock at a 30-45 degree angle. Once near the dock, move the throttle bar toward the dock to clear the bow
of the boat and take up a parallel position. Nearer the dock, move the bar to the other side, slow the throttle and for a instant the
boat will back up, bringing the stern close to the dock. Once alongside the dock, moor the boat. If the wind is blowing toward the dock, it
is best to approach from a wider angle. If the wind is blowing from the dock, approach at a narrower angle.
Launching from Shore
In fair weather, launching a boat from shore is relatively easy. With the motor raised, the boat is lifted and pushed into the water, front
first. Once the boat is afloat, with the stern barely touching the shore, hold it at a 90-degree angle to the shore in order to board,
first in the centre, and then at the bow. Lastly, the driver shoves the boat out into the water, walking alongside in the water, and boards
at the stern. When launching, the person in the centre nudges the boat out into the water with an oar until the water is deep enough to
start the motor. This person can also guide the boat in the desired direction. Then, after starting the motor, shift to Forward,
gaining speed as the boat moves farther from shore.
Landing on Shore
To land on shore in fair weather, stop the motor where the water is still fairly deep and tilt it out of the water to prevent damaging the propeller.
It is important for the driver to instinctively know the location of the stop mechanism and the tilting lever. To lighten the front
end, any passengers in the bow of the boat will move to the centre and row to shore. On reaching the shore, one person sets foot on the ground
and holds the boat steady while the other passengers step out. Once the boat is empty, it can be lifted and carried to the shore for mooring.
Avoid pushing the boat ashore.
In poor weather, it is best to approach the shore backwards. This will prevent water from accumulating in the boat. With the motor
running, turn the boat so that the stern is toward shore. The centre passenger holds this course with the oar. Then, stop the motor and
tilt it out of the water. The waves will carry the boat to shore. To prevent the stern from dipping into the trough of the
waves as they strike the bow, the rower pulls gently on the oars.
Accelerating and Planing
Acceleration tends to make a boat leave the water and hydroplane on the surface; this movement is triggered by the wash of the motor. It
lifts the boat by several degrees. This seriously diminishes the operators visibility in front of the boat and makes it more difficult
to effectively use the motors propulsion force. To correct this situation, simply accelerate slightly to pass over the wave and
regain a relatively horizontal trim.
Operating in Waves
In poor weather, to reduce the risk of capsizing or taking on water, waves must be crossed bow first. With a motor, the boats speed can be quickly adjusted to synchronize its forward motion with the movement of the waves. In this way, the bow crosses the waves more easily.
Certain rules of thumb can improve towing efficiency:
- Towing is faster if the other boat is pulled rather than coupled alongside the towing boat. However, coupling is better when the boat being towed lacks maneuverability, since the towing boat can steer it to some extent. This technique is also used when the boat being towed is unstable.
- To tow a boat and its passengers, it must be stable and the towing boat operator must be warned of any problems immediately
- The two boats must be aligned in the same direction.
- The towing boat operator must constantly monitor the situation.
- A canoe can be towed using a rope secured around the tip of the bow. Other types of vessels are equipped with rings used to secure a hitch (towing rope) to a towing boat.
Sometimes, towing is the worst option. The first role of the rescuer is to save lives and reduce human suffering. When
boating conditions prevent towing, specialized towing companies can be called in for assistance. The same applies when the boat will not
stand up to towing (see manufacturers recommended limits) or was not designed for towing (such as inflatable crafts).
To make the towed boat easier to maneuver, fasten the hitch fairly close to the waterline at the centre of the bow. Some boats have lugs or hooks for fastening a hitch.
In poor weather, the length of the tow line depends on the waves. To avoid collision, synchronize the speed of the two boats and their movement over the crest or trough of the waves.
It is extremely important that both vessels are cresting the waves at the same time. The length of towing rope should be adjusted to ensure that the vessels are properly spaced.
Towing is more effective if the traction point is located in the rear centre of the towing boat. This is done simply if a ring or lug is installed at the centre of the stern. Otherwise, a V-shaped rope assembly can prevent sideways traction on the towing boat. A hitch attached to a V-assembly can slide from side to side.
The towing speed depends on the boat type, weight and means of propulsion. It must be adjusted to keep the towed boat steady. Where
a motor boat is used, avoid placing excessive strain on the motor.
If possible, the hitch should be easy to cast off. The knots used in a hitch must be able to withstand considerable and variable strain. The
bowline knot is the most commonly used. round turn knot and two half hitches can be used for towing light loads. However, never use a
square knot or a clove hitch for towing.
Responding to Breakdowns
Know the following actions to take in response to breakdowns on board a boat:
- Alter the speed of the craft as appropriate to the circumstances
- Anchor the craft as appropriate to the circumstances
- Investigate the problem
- Correct the problem if possible
- Use or exhibit signals to indicate distress and need of assistance if necessary.
Operating a boat safely demands that operators develop alertness, judgment, caution and foresight.
- Carefully monitor the surroundings;
- Observe and assess navigation conditions, weather changes and passengers behaviour.
- Assess whether the boat is adequate to meet the navigation conditions;
- Choose the best route.
- Operate the boat to suit weather conditions (e.g., it is important to slow down in bad weather to avoid losing control of the pleasure craft, which could increase the risk of injuries or loss of life aboard).
Caution and foresight
- Assess the risks involved in each maneuver;
- Plan what route to take;
- Accept your own limits as a boat operator.
- Be thoroughly familiar with your boat and its maneuvering capacities (e.g., know that a pleasure craft traveling at high speeds requires more distance to stop in case of an emergency, and that its operator must be even more alert since he/she has less time to react to new conditions).
Provisions of the Collision Regulations pertaining to lights and shapes.
- A masthead light means a white light placed over the fore and aft centerline of a pleasure craft showing an unbroken light over
an arc of the horizon of 225 degrees and so fixed as to show the light from right ahead to 22.5 degrees abaft the beam on either side of a pleasure
craft as described in the collision Regulations, Rule 21
- Sidelights means a green light on the starboard side and a red light on the port side each showing an unbroken light over an arc
of the horizon of 112.5 degrees and so fixed as to show the light from right ahead to 22.5 degrees abaft the beam on its respective side as
described in the Collision Regulations, Rule 21
- A stern light means a white light placed as nearly as practical at the stern showing an unbroken light over an arc of the horizon
of 135 degrees and so fixed as to show the light 67.5 degrees from right aft on each side of a pleasure craft as described in the Collision
Regulations, Rule 21.
- An all-round light means a light showing an unbroken light over an arc of the horizon of 360 degrees as described in the Collision
Regulations, Rule 21.
- The operator of a pleasure power driven craft underway shall, from sunset to sunrise, exhibit a masthead light forward, sidelights, and a stern
light as described in the Collision Regulations, Rules 20 and 23.
- The operator of a pleasure power driven craft of less than 12 metres in length underway, may exhibit, from sunset to sunrise, in lieu of a masthead
light forward, sidelights, and a stern light, an all-round white light and sidelights as described in the Collision Regulations, Rules 20 and
- The operator of a pleasure sailing craft underway shall, from sunset to sunrise, exhibit sidelights and a stern light as described in the Collision
Regulations, Rules 20 and 25.
- The operator of a pleasure sailing craft of less than 20 metres in length underway may exhibit, from sunset to sunrise, in lieu of sidelights
and a stern light, a combined sidelights and stern light in one lantern carried at or near the top of the mast as described in the Collision
Regulations, Rules 20 and 25.
- The operator of a pleasure sailing craft of less than 7 metres in length underway shall, from sunset to sunrise, exhibit, if practical, sidelights
and a stern light, but if the operator cannot, he/she shall have ready at hand an electric torch or lighted lantern showing a white light which
shall be exhibited in sufficient time to prevent collision as described in the Collision Regulations, Rules 20 and 25.
- The operator of a pleasure craft under oars may exhibit, from sunset to sunrise, sidelights and a stern light, but if the operator does not,
he/she shall have ready at hand an electric torch or lighted lantern showing a white light which shall be exhibited in sufficient time to prevent
collision as described in the Collision Regulations, Rules 20 and 25.
- The operator of a pleasure craft of less than 50 metres in length at anchor shall exhibit, from sunset to sunrise, in the fore part an all-round
white light as described in the Collision Regulations, Rules 20 and 30.
Collision Regulations pertaining to sound and light signals
- The operator of a pleasure craft of less than 12 metres shall carry sound signaling appliances or some other means of
making an efficient sound signal as described in the collision Regulations, Rule 33.
- The operator of a pleasure craft in or near an area of restricted visibility, whether by day or night, may sound a combination of prolonged
and short blasts using the whistle or sound signaling appliances of the pleasure craft to indicate presence as described in the Collision Regulations, Rule 35.
- The operator of a pleasure craft shall recognize, use or exhibit the following signals to indicate distress and need of assistance as described in Collision Regulations, Rule 37 and Annex IV:
- A gun or other explosive signal fired at intervals of about a minute;
- A continuous sounding with any fog-signaling apparatus;
- Rockets or shells, throwing red stars fired one at a time at short intervals;
- A signal made by any signaling method consisting of the group ...---... (S.O.S.) in the Morse Code;
- A signal sent by radiotelephony consisting of the spoken word MAYDAY;
- The International Code Signal of distress indicated by the flags N and C;
- A signal consisting of a square flag having above or below it a ball or anything resembling a ball;
- Flames on the vessel;
- A rocket parachute flare or hand flare showing a red light;
- A smoke signal giving off orange coloured smoke;
- Slowly and repeatedly raising and lowering arms outstretched to each side;
- Signals transmitted by emergency position indicating radio beacons (EPIRB);
- A piece of orange canvas with either a black square and circle or other symbol appropriate for identification from the air;
- Dye marker;
- A square shape or anything resembling a square shape; or
- A high intensity white light flashing at regular intervals of 50 to 70 times per minute.
Collision Regulations pertaining to additional provisions.
- The operator of a pleasure craft that is less than 20 metres in length or a pleasure sailing craft shall not impede the safe passage of a power
driven vessel following a traffic lane as described in the Collision Regulations, Rule 10.
- The operator of a pleasure power driven craft shall take early and substantial action to keep well clear of a vessel engaged in fishing, or
a sailing vessel as described in the Collision regulations, Rules 16 and 18 (a).
- The operator of a pleasure sailing craft shall take early and substantial action to keep well clear of a vessel engaged in fishing as described
in the Collision regulations, Rules 16 and 18(b).
Standard Marine Distress Signals
If you see a distress signal, you are required by law to determine whether you can assist those in distress without endangering your own life
or safety of your vessel. Where possible, you must also contact the nearest Rescue Coordination Center to inform them of the type and location
of the distress signal you have seen.
Knowing the following distress signals will help you call for help in an emergency and recognize those in trouble.
Not only is it against the law to make a false distress signal, but false alarms commit search and rescue personnel making them potentially unavailable or further away from real emergencies.
Use 2182 kHz (MF) or channel 16, 156.8 MHz (VHF) DSC alert, channel 70 (only for DSC type radios and where the service is offered.)
Mayday, Mayday, Mayday Immediate danger for persons OR ship
Pan-Pan, Pan-Pan, Pan-Pan Urgent message concerning safety of a person or ship
- Give vessel name and call sign
- State position of vessel
- Describe nature of emergency
To attract attention, spread on
cabin or deck top, or fly from mast.
Raise and lower outstretched
Continuous sounding with any fog-signaling apparatus. Gun
or other explosive signal fired at intervals of about a minute.
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