Yanmar marine engine 6LPA-STP2, 6LPA-STZP2. Manual - part 3

PRODUCT OVERVIEW

6LPA Series Operation Manual

11

12/05

COMPONENT IDENTIFICATION

Service Side (Left Side as Viewed from Propeller)

Note: 6LPA-STZP2 with stern drive shown. Components marked with an * are for 

6LPA-STZP2 only.

 Figure 1

Figure 1 

1 – Fuel  Cooler
2 – Fuel Filter
3 – Power Steering Oil Cooler*
4 – Engine Oil Filter
5 – Intercooler
6 – Mixing Elbow

7 – Engine Oil Cooler
8 – Starter
9 – Engine Oil Cooler

10 – Fuel Injection Pump
11 – Seawater Pump
12 – Stern  Drive

(1)

(2)

(3)

(4)

(5)

(6)

(12)

(11)

(10)

(9)

(8)

(7)

0004884

PRODUCT OVERVIEW

12

6LPA Series Operation Manual

Non-Service Side

 Figure 2

Figure 2 

1 – Turbocharger
2 – Engine Nameplate (on rocker 

arm cover)

3 – Fresh Water (Coolant) Tank
4 – Power Steering Oil Tank*
5 – Fresh Water Filler Cap

6 – Engine Oil Filler Cap
7 – Power Steering Oil Pump*
8 – Alternator
9 – Engine Oil Dipstick

10 – Fresh Water Cooler
11 – V-Belt

(1)

(2)

(3)

(4)

(5)

(6)

(7)

(8)

(9)

(10)

(11)

0004885

PRODUCT OVERVIEW

6LPA Series Operation Manual

13

12/05

NAMEPLATES

The nameplate of Yanmar 6LPA series 
engines is shown in Figure 3. The 
nameplate is located on the engine rocker 
arm cover. Check the engine's model, 
output, rpm and serial number on the 
nameplate. Replace if damaged or lost.

Figure 3 

Gear Model

ENG.No.

Model

min

-1

min

-1

min

-1

Speed of prop shaft

Fuel stop power kW

Continuous power kW

/

/

0004574

PRODUCT OVERVIEW

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6LPA Series Operation Manual

FUNCTION OF MAJOR COMPONENTS

Name of Component 

Function 

Fuel Filter 

Removes dirt and water from the fuel. The filter is a cartridge type, and the inner 
element should be replaced before clogging occurs. A water separator is on the 
bottom of the filter and should be drained periodically.

Fuel Feed Pump 

A mechanical pump that pumps fuel from the tank to the fuel injection pump. It is 
built in to the fuel injection pump.

Fuel Bleed Pump 

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 should 
be replaced periodically. 

Engine Oil Dipstick

Gauge stick for checking the engine oil level.

Marine Gear Oil Filler Port (If 
Equipped)

Filler port for marine gear lube oil. Located on top of the marine gear case.

Cooling System 

There are two cooling systems: coolant and seawater.

• Coolant Tank 
• Heat Exchanger 
• Coolant Pump

The tank stores the coolant and is connected to the heat exchanger. Cooling 
seawater passes through the heat exchanger to cool the coolant by heat 
exchange. After cooling, the coolant is fed by the coolant pump to the inside of 
the engine, around the combustion chamber, turbocharger and then returned to 
the tank.

Filler Cap

Located on the top of the coolant tank. It has two pressure regulating valves 
(release and retraction valves). When the coolant temperature rises, the 
pressure inside the coolant tank increases causing the release valve in the filler 
cap to open.

Reservoir

Hot water and steam pass through a rubber hose to the reservoir for cooling. (The 
filler port and the reservoir are connected by a rubber hose.) When the load is 
reduced and the coolant temperature falls, the pressure in the coolant tank is 
lowered, activating the retraction valve in the filler cap. This causes the coolant 
in the reservoir to return to the coolant tank. This process reduces the 
consumption of coolant.

Turbocharger 

A pressurized intake air feeding device. The exhaust gas turbine is rotated by the 
exhaust gas and the power is used to rotate the blower. This pressurizes the 
intake air for sending to the cylinder.

Charge air cooler

This heat exchanger cools the pressurized charging air from the turbocharger 
with water.

Zinc Anode

The metal area of the seawater cooling system is prone to galvanic corrosion. 
The zinc anode is installed in the various coolers to prevent this. When the zinc 
anode becomes worn, components in the fresh water cooler, oil cooler, etc. will 
corrode. Periodic replacement of the zinc anode is necessary.

Nameplates 

Nameplates are provided on the engine and have the model, serial number and 
other data. 

Starter 

A DC motor for starting the engine. Electric current causes the pinion gear to 
engage with the ring gear on the flywheel to start the engine.

Alternator 

This generator rotates by a V-belt drive to charge the battery during operation.