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.
Fuel Priming Pump (if
equipped)
This is a manual fuel pump. Pushing the knob on the top of the fuel filter feeds the
fuel. The pump is also used to bleed air from the fuel system.
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 and
Replacing the Engine Oil Filter Element on page 69.
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 and intake air (depending on model) through the cooler(s)
in an open circuit.
Closed Cooling
Circulation Pump
The centrifugal water pump circulates coolant inside the engine. The circulating
pump is driven by a V-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
When the coolant temperature rises, the pressure inside the fresh water tank
increases and opens the pressure valve in the filler cap. When the pressure valve
in the filler cap is opened, hot water and steam pass through a rubber hose to the
coolant recovery tank. When the engine cools and the pressure inside the coolant
recovery tank drops, the vacuum valve in the filler cap opens and the coolant in
the coolant recovery tank returns to the water tank through the pipe and filler cap.
This minimizes coolant consumption.
Coolant Recovery Tank
The pressure valve in the filler cap releases vapor and hot water overflow to the
coolant recovery tank. 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 coolant recovery tank. This minimizes coolant consumptions. The
closed cooling system coolant level can easily be checked and refilled in this tank.
Oil Cooler - Engine
A heat exchanger that cools high temperature engine oil using coolant.
Oil Cooler - Marine Gear
(Optional)
This heat exchanger that cools the marine gear (KMH4A) oil using seawater.
Turbocharger (if
equipped)
The turbocharger pressurizes the air coming into the engine. It is driven by a turbine
that is energized by exhaust gases.
Intercooler (if equipped)
This heat exchanger cools the pressurized charging air from the turbocharger with
seawater to increase the charging air quantity.
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.
Starter
Starter motor for the engine. Powered by the battery.
Alternator
Driven by belt and generates electricity and charges the battery.
Engine Oil Dipstick
Gauge stick for checking the engine oil level.
PRODUCT OVERVIEW
20
JH4 Series Operation Manual
Summary of Contents for 3JH4E
Page 1: ...JH4 series OPERATION MANUAL 3JH4E 4JH4AE 4JH4 TE 4JH4 HTE P N 0AJH4 G00102 MARINE ENGINES ...
Page 18: ...This Page Intentionally Left Blank SAFETY 12 JH4 Series Operation Manual ...
Page 48: ...This Page Intentionally Left Blank BEFORE YOU OPERATE 42 JH4 Series Operation Manual ...
Page 56: ...This Page Intentionally Left Blank ENGINE OPERATION 50 JH4 Series Operation Manual ...
Page 82: ...This Page Intentionally Left Blank PERIODIC MAINTENANCE 76 JH4 Series Operation Manual ...
Page 101: ...This Page Intentionally Left Blank SPECIFICATIONS JH4 Series Operation Manual 95 ...
Page 134: ...This Page Intentionally Left Blank SYSTEM DIAGRAMS 128 JH4 Series Operation Manual ...
Page 142: ...136 JH4 Series Operation Manual ...