Ignition
keyturning a key and it is not clear why this is so. Surely there are better ways to secure a boat from theft. A key that protrudes from the control panel can be broken off easily by crew moving about in the cockpit. At best, this would require tedious removal with needle nose pliers or tweezers. Failing that, it will be difficult to start the engine. A broken off key is therefore a hazard when underway.
Whether the engine can operate with the key removed depends on how it is wired. If the voltage regulator and other electrical components all continue to operate when the key is removed, it is wise to remove it immediately after starting the engine. If the alternator field current is wired through the ignition key, as in an automobile, removing the key will prevent the battery from charging. Attach the ignition key to a floating key holder and carry at least one spare onboard.
Shift
leverFreewheeling the prop while sailing cannot harm the transmission, and offers lever slightly less drag, but it makes annoying noise and causes wear on the shaft bearings. Sailing in either forward or reverse gear is fine as long as the prop shaft does not move. Whether the shaft will turn, while sailing in forward or reverse, depends on the type of engagement mechanism, or clutch, inside the transmission. If the shaft turns while in gear, that clutch will wear and eventually fail. What you want, therefore, is the setting—either forward or, more commonly, reverse—where the shaft does not neutral.
Stop
controlA diesel engine stop control shuts off the fuel supply. Unless it is control electrical, lube it at the first sign of sticking by disconnecting the cockpit end of the cable, taping the mouth of a strong baggie onto the end, filling the baggie with oil through a slit in its bottom, and suspending it high so that oil can seep down into the cable overnight. If you cannot stop the engine with the control, go below and operate the lever arm that this cable connects to.
Electric stop controls can be on to stop, where the control activates a solenoid that pushes against a spring, or on to run, where the control activates the injector pump. When electrical power is lost, the engine will stop if the control is of the on-to-run type, or else it will be difficult to stop without cutting off fuel, perhaps by clamping a hose.
TachometerThe mechanical tachs on older engines are simple and reliable if you keep their cable lubed, just as for the stop control. Newer engines use an electronic tach with a sender that senses either the flywheel rotation or the alternator stator current at a terminal usually marked R. After changing the alternator or any of its drive pulleys, a tach that attaches to the alternator must be recalibrated by marking the flywheel, using a photo-tachometer to measure engine RPM, and adjusting the tach to show that value. you first turn on the ignition key, before starting the engine. It measures alternator output voltage while the engine is running. The battery voltage should be below but close to 12.6, in a 12-volt system, and the alternator voltage should be a bit above 13.5 shortly after starting the engine. Low alternator voltage upon start-up, before the battery has recharged and the voltage regulator kicks in, generally indicates a loose alternator belt, which can also make the tachometer read low.
Warning
lights
and
buzzersThe low oil pressure light or buzzer comes on when oil and buzzers pressure drops to about 5 psi while the ignition key is on. Stop the engine immediately, if this occurs, or it will seize up within seconds. Check the oil level, and if it is normal, change the oil and filter. If you have an oil pressure gauge, close the raw water intake, engage the engine stop control, and crank the engine at 10-second intervals every few minutes until oil pressure appears, then re-open the raw water seacock.
The high water temperature warning light or buzzer comes on if the coolant temperature reaches about 215°F. The charging warning light, or ignition light, goes out as soon as the alternator begins to produce charging current. Seeing this light come on while the engine is running usually indicates that the v-belt has failed. If that belt also drives the raw water pump, the next thing you will get is a high temperature warning.
autopilot can steer the boat— effortlessly, without much attention, and better than any helmsman—on a straight course or even along a chain of waypoints. It can take over for a brief time, while the helmsman attends to something, or for hours while traversing a channel or canal. On a long passage inland, such as down the ICW, an autopilot is almost essential. Some autopilots attach to the steering wheel by means of a notched belt. Others attach to an arm on the rudder post by means of a hydraulic cylinder. Rudder post autopilots are much stronger, which means they can be used in heavier air, and they can also substitute for an emergency tiller. Autopilots that attach to the steering wheel take less power and are more suitable for smaller boats sailed mainly close to shore. Many autopilots have buttons for making course changes of 10 degrees and one degree. When using the 1-degree button, click it always three times because three degrees is the least that you can discern while at the helm. There might also be a responsiveness setting that determines how sensitive the unit is to course changes. A high response setting makes the unit “steer small” by making frequent changes that can waste battery power. The lowest response setting is often the best, for sailboats, even when motoring.