Sailboat Inboard Engines


	The Engine : Most inboard sailboat engines are diesel as opposed to using gasoline. Diesel engines have no spark plugs or points, the fuel is ignited by compression not by an electrical spark. Diesel fuel is also less explosive than gasoline and not as likely to produce carbon monoxide. Thus, it is safer to have onboard. Fuel is placed into the sailboat by way of a deck fill (see picture on the right). The deck fill is often keyed to be opened using a winch handle. Some deck fills are opened by a special tool or have a built in handle. Marine fueling systems deliver fuel at a very high rate to rapidly transfer hundreds of gallons of fuel into large yachts. The fueling system does not have an automatic shut-off once the tank is full. Thus, one should always estimate the fuel needed first by referring to the sailboat's fuel gauge and fuel tank capacity and do not try to fill the tank to the top. Unlike fueling a car, if you spill fuel into the water you can be fined. Thus, when only placing 10 gallons into the tank try to do it slowly and always have an absorbent nearby to mop up potential spills. The following steps should be taken to turn on the engine: First turn the battery switch to "All". Make sure the throttle is at the lowest setting, the transmission is in neutral. If your sailboat is equipped with a Bilge Blower, run it for at least 5 minutes. Make sure the transmission is in neutral. Make sure the fuel shut-off handle is pushed in. If equipped with a Glow Plug or pre-heater, operate the glow plug for approximately 20 seconds. Now start the engine with the key. Following steps are taken to turn off the engine: Make sure the throttle is at the lowest setting the the transmission is in neutral. Pull out the fuel kill valve. Once the engine stops turn the key off. After the engine stops turn the battery switch to "1", "2" or "OFF". Note: Turning off the engine with the key before pulling out the fuel kill valve can ruin the alternator.
	The Cooling System: The cooling system is crucial for the operation of the engine. There are two separate water systems which cool the engine. The first is the raw water system. This system transports the cool seawater next to the engine's closed (coolant) system and out the engine's exhaust through-hull. The seawater in the raw water system does not physically mix with the coolant in the engine's closed system. Before starting the engine, be sure the seacock for the raw water intake is open and the raw water ( sea ) strainer (red arrow in picture on the right) is not clogged. After starting the engine ALWAYS check to make sure water is spitting out the engine's exhaust. If the exhaust through-hull is not spitting water turn the engine off immediately. The following problems may exist: 1) The raw water intake seacock is closed. 2) The intake through-hull is clogged. 3) The sea strainer is clogged. 4) There is a hole in the raw water system. If the problem is located before the raw water reaches the engine, then the engine will overheat if it is running. If there is a hole in the system after the raw water leaves the engine, then the engine will not overheat but water and exhaust will be pumped into the inside of the boat. The closed system circulates through the engine and the coolant fluids are cooled by the raw water system. Engine coolant is placed into the engine by removing the coolant cap. ONLY DO THIS IF THE ENGINE IS COOL. Only twist the coolant cap part way at first to release any potential steam, then take off to check the coolant level. The level of the fluid in the closed system's reservoir should be about one inch form the top.
	The Engine: Shown in this picture is the (A) coolant cap, (B) high pressure injector lines, (C) the closed system's water pump, (D) the engine's belt, (E) the alternator and (F) the raw water system's pump. Before starting a voyage always check the coolant level and the integrity of the engine belt. In newer boats, a plastic chamber is used to check and add coolant and not the cap. Note that below the engine is a white absorbent cloth, this cloth aids in the detection of engine fluid leaks and will prevent small leaks from entering the bilge and being pumped out to sea.
	Oil Dip Stick: Before starting each day be sure to check the oil level using the oil dip stick . The dip stick (red arrow in picture on the right) is often located on the side of the engine. It is usually accessed through a panel in the quarter berth (the stern compartment).
	Fuel Water Separator: Before the fuel is pumped into the engine it enters a fuel water separator, often this assembly also contains the primary fuel filter (red arrow in picture on the right). Fuel floats to the top and water stays on the bottom. The water can be drained by loosening a small nut at the bottom of the separator.
	The Stuffing Box: The propeller shaft leaves the engine's transmission and exits the sailboat's hull through a fitting called the "Stuffing Box" (red arrow in picture on the right). The "Stuffing Box" forms a seal and prevents the boat from being flooded. However, in many boats, a small amount of water does intermittently seep in. This water enters the bilge and is pumped out by the bilge pump. Thus, the bilge pump will intermittently turn on to remove this water. In newer boats, a deep-sea ("dripless") seal may be present.
	The Bilge Pump: The bilge is the lowest part of the boat. A bilge pump (red arrow in picture on the right) intermittently removes this water. The pump's switch on the boat's electrical panel should be set on automatic. In this setting, the pumps floater switch will turn the pump on when the bulge's water level reaches a certain height. It is normal for the bilge pump to intermittently turn on though out the day.

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