PRODUCT OVERVIEW 12/05 FUNCTION OF MAJOR COMPONENTS Name of Component Function Fuel Filter Removes dirt and water from the fuel. Drain the filter periodically. The filter element should be replaced periodically. The water separator (if equipped) should be drained periodically. See Draining Fuel Filter / Water Separator on page 65. Fuel Feed Pump Pumps fuel from the tank to the fuel injection system. Pushing the manual lever on the side of the feed pump supplies fuel to the engine when fuel priming is needed. Fuel Feed Lever Moving the fuel feed lever up and down feeds the fuel. The lever is used to bleed air from the fuel system after running out of fuel.
Engine Oil Filler Port Filler port for engine oil. Engine Oil Filter Filters fine metal fragments and carbon from the engine oil. Filtered engine oil is distributed to the engine’s moving parts. The filter is a cartridge type and the element should be replaced periodically. See Changing the Engine Oil on page 61. Marine Gear Filler Port Filler port for marine gear lube oil. Located on top of the marine gear case. Cooling System There are two cooling systems: closed cooling with coolant (fresh water) and seawater. The engine is cooled by the closed cooling circuit. The closed circuit is cooled by seawater using a heat exchanger. The seawater also cools the engine / marine gear oil.
Closed Cooling Circulation Pump The centrifugal water pump circulates coolant inside the engine. The circulating pump is driven by a V-ribbed belt. Seawater Pump Pumps seawater from outside vessel to the engine. The seawater pump is gear-driven and has a replaceable rubber impeller. Do not operate it without seawater, as this will damage the impeller. Coolant Filler Cap The filler cap on the heat exchanger / coolant tank covers the water supply port. The cap has a pressure regulating valve. When the cooling water temperature rises, the pressure rises inside the coolant system. Reservoir The pressure valve in the filler cap releases vapor and hot water overflow to the reservoir.
When the engine stops and the coolant cools, the pressure in the coolant tank drops. The filler cap vacuum valve then opens to send water back from the reservoir. This minimizes coolant consumption. The closed cooling system coolant level can easily be checked and refilled in this tank. Engine Oil Cooler A heat exchanger that cools high temperature engine oil using coolant. Intake Silencer (Air Cleaner) The intake silencer guards against dirt in the air and reduces the noise of air intake. Nameplates Nameplates are provided on the engine and the marine gear and have the model, serial number and other data.
See Nameplates on page 16 Starter Starter motor for the engine; powered by the battery. Alternator Driven by a belt and generates electricity and charges the battery. Engine Oil Dipstick Gauge stick for checking the engine oil level. YM Series Operation Manual 17