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Yanmar marine engine 6LPA-STP2, 6LPA-STZP2. Manual - part 18

TROUBLESHOOTING

6LPA Series Operation Manual

12/05

TROUBLESHOOTING CHART

Symptom

Probable Cause

Measure

Reference

Indicators light on the

instrument panel and alarm

sounds during operation

Shift to low speed operation immediately, and check which indicator has come on.

Stop the engine and inspect. If no abnormality is identified and there is no problem

with operation, return to port at lowest speed and request repairs.

• Engine oil low pressure

alarm indicator comes on

Engine oil level is low.

Check engine oil level. Add

or replace.

See Adding Engine Oil
on page 31

Engine oil filter clogged.

Replace engine oil filter.

Replace engine oil.

See Changing the
Engine Oil and Replacing
the Engine Oil Filter
Element on page 57

• Fresh water (coolant)

level alarm comes on

Coolant / fresh water in

coolant recovery tank is

low.

Check coolant level and

refill.

See Checking and
Adding Coolant on
page 34

• Fresh water (coolant)

high temperature alarm

comes on

Coolant / fresh water in

coolant recovery tank is

low.

Check coolant level and

refill.

See Checking and
Adding Coolant on
page 34

Leakage in fresh water

cooling system causing

temperature to rise.

See your authorized

Yanmar Marine dealer or

distributor.

Contamination inside

cooling system.

See your authorized

Yanmar Marine dealer or

distributor.

Fresh water cooling pump

damaged.

See your authorized

Yanmar Marine dealer or

distributor.

• Gear oil alarm comes on Insufficient drive oil.

Check oil level and refill.

See Marine Drive Oil on
page 32

• Fuel filter alarm comes

Water level in fuel / water

separator too high.

Drain.

See Draining Fuel Filter /
Water Separator on
page 60

• Exhaust alarm comes on Insufficient discharge of

cooling seawater.Check

that seacock is

open.Damaged seawater

pump.

See your authorized

Yanmar Marine dealer or

distributor.

Faulty Warning Devices

Do not operate the engine if alarm devices are not repaired. Serious accidents may

result if abnormalities are not identified due to faulty indicators or alarm.

Indicators Do Not Go On:
• When key is turned ON
• When any trouble occurs

(oil pressure etc.)

No electrical current

available. Circuit broken

or lamp burned out.

See your authorized

Yanmar Marine dealer or

distributor.

• One of the indicators

does not go out

Sensor switch is faulty.

See your authorized

Yanmar Marine dealer or

distributor.

• Battery low charge

indicator does not go out

during operation

V-belt is loose or broken.

Replace V-belt or adjust

tension.

See Checking and
Adjusting the Alternator
V-Belt Tension on
page 66

Battery is defective.

Check battery fluid level,

specific gravity or replace

battery.

See Checking the Battery
Electrolyte Level on
page 57

Alternator power

generation failure.

See your authorized

Yanmar Marine dealer or

distributor.

TROUBLESHOOTING

6LPA Series Operation Manual

Starting Failures:
• Starter turns but engine

does not start

No fuel.

Add fuel. Bleed fuel

system.

See Filling the Fuel Tank
on page 28

and See

Bleeding the Fuel
System on page 29

Air in fuel line.

Bleed fuel system.

See Bleeding the Fuel
System on page 29

Fuel filter is clogged.

Replace filter element.

See Replacing the Fuel
Filter Element on page 63

Improper fuel.

Replace with

recommended fuel.

See Diesel Fuel
Specifications on page 26

Problem with fuel

injection.

See your authorized Yanmar

Marine dealer or distributor.

Compression leakage

from intake / exhaust

valve.

See your authorized

Yanmar Marine dealer or

distributor.

• Starter does not turn or

turns slowly (engine can

be turned manually)

Faulty clutch position.

Shift to NEUTRAL and

start.

Insufficient battery

charge.

Check fluid level.

Recharge. Replace.

See Checking the Battery
Electrolyte Level on
page 57

Cable terminal contact

failure.

Remove corrosion from

terminals. Tighten battery

cables.

Faulty safety switch

device.

See your authorized Yanmar

Marine dealer or distributor.

Faulty starter switch.

See your authorized Yanmar

Marine dealer or distributor.

Power lacking due to

accessory drive being

engaged.

See your authorized Yanmar

Marine dealer or distributor.

• Engine cannot be turned

manually

Internal parts seized.

See your authorized Yanmar

Marine dealer or distributor.

Abnormal Exhaust Color:
• Black smoke

Overload

Reduce load.

Improper propeller

matching.

See your authorized Yanmar

Marine dealer or distributor.

Dirty air cleaner.

Clean air cleaner.

See Cleaning the Air
Cleaner on page 65

Improper fuel.

Replace with

recommended fuel.

See Diesel Fuel
Specifications on page 26

Faulty spraying of fuel

injector.

See your authorized Yanmar

Marine dealer or distributor.

Low boost pressure.

See your authorized Yanmar

Marine dealer or distributor.

Incorrect intake / exhaust

valve clearance.

See your authorized Yanmar

Marine dealer or distributor.

• White smoke

Improper fuel.

Replace with

recommended fuel.

See Diesel Fuel
Specifications on page 26

Faulty spraying of fuel

injector.

See your authorized Yanmar

Marine dealer or distributor.

Fuel injection timing off.

See your authorized Yanmar

Marine dealer or distributor.

Engine burning oil

(excessive consumption).

See your authorized Yanmar

Marine dealer or distributor.

Symptom

Probable Cause

Measure

Reference

6LPA Series Operation Manual

LONG-TERM STORAGE

If the engine will not be used for an
extended period of time, special measures
should be taken to protect the cooling
system, fuel system and combustion
chamber from corrosion and the exterior
from rusting.

The engine can normally stand idle for up
to 6 months. If it remains unused for longer
than this, please contact your authorized
Yanmar Marine dealer or distributor.

Before performing any storage procedures
within this section, review the Safety
section on page 3.

In cold temperatures or before long-term
storage, be sure to drain the seawater from
the cooling system.

NOTICE

DO NOT drain the coolant system. A full
coolant system will prevent corrosion and
frost damage.

If seawater is left inside of the engine, it
may freeze and damage parts of the
cooling system when the ambient
temperature is below 0°C (32°F).

PREPARE ENGINE FOR
LONG-TERM STORAGE

Note: If the engine is close to a

periodic maintenance interval,
perform those maintenance
procedures before putting the
engine into long-term storage.

1. Wipe off any dust or oil from the outside

of engine.

2. Drain water from fuel filters.
3. Drain fuel tank completely or fill the

tank to prevent condensation.

4. Grease the exposed areas and joints of

the remote control cables and the
bearings of the remote control handle.

5. Seal the intake silencer, exhaust pipe,

etc. to prevent moisture or
contamination from entering engine.

6. Completely drain bilge in hull bottom.
7. Waterproof the engine room to prevent

rain or seawater from entering.

8. Charge the battery once a month to

compensate for battery’s
self-discharge.

9. Remove key from key switch and cover

the key switch with moisture cap.

LONG-TERM STORAGE

6LPA Series Operation Manual

DRAIN SEAWATER
COOLING SYSTEM

Figure 1

Figure 1

Figure 2

Figure 2

Figure 3

Figure 3

Figure 4

Figure 4

1 – Seawater Drain Cock
2 – Fresh Water Drain Cock
3 – Fresh Water Drain Cock
4 – Seawater Pump Cover
5 – Seawater Drain Cock

NOTICE

If seawater is left inside, it may freeze and
damage parts of the cooling system (heat
exchanger, seawater pump, etc.) when
ambient temperature is below 32°F (0°C).

1. Close the seacock.
2. Open the seawater drain cocks and

drain off the seawater.

3. Remove four bolts attaching the side

cover of the seawater pump. Remove
the cover and drain the seawater.

4. Install cover and tighten bolts.
5. Close all the drain cocks.

(2)

(1)

0004904

(3)

0004905

(4)

0004906

(5)

0004907

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