Yamaha 115 C Service Manual

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EMN00010
Chapter 5
TROUBLE RECOVERY
TROUBLESHOOTING..............................5-1
TEMPORARY ACTION 
IN EMERGENCY.......................................5-5
Impact damage .....................................5-5
Power trim / tilt will not operate .........5-5
Starter will not operate ........................5-6
Engine fails to operate .........................5-8
Low oil level warning activates...........5-9
Top cowling does not unlock ............5-10
Treatment of submerged motor .......5-11
1
2
3
4...

5-1
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EMU01204¯
TROUBLESHOOTING
A problem in the fuel, compression, or ignition systems can cause poor starting, loss of
power, or other problems. The troubleshooting chart describes basic checks and possi-
ble remedies. (This chart covers all Yamaha outboard motors. Therefore, some items
may not apply to your model.)
If your outboard motor requires repair, bring it to a Yamaha dealer.
A. Starter will not
operate.Trouble Possible Cause Remedy
1. Battery capacity weak or low.
2. Battery connections loose...

5-2
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C. Engine idles
irregularly or stalls.Trouble Possible Cause Remedy
1. Spark plug(s) fouled or incorrect
type.
2. Fuel system obstructed.
3. Fuel contaminated or stale.
4. Fuel filter clogged.
5. Failed ignition parts.
6. Warning system activated.
7. Spark plug gap incorrect.
8. Poor connections or damaged
ignition wiring.
9. Specified engine oil not used.
10. Thermostat faulty or clogged.
11. Carburetor adjustments incorrect.
12. Fuel pump damaged.
13. Air vent screw on the fuel tank
closed.
14....

5-3
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D. Warning buzzer
sounds or
indicator lamp
lights.Trouble Possible Cause Remedy
1. Cooling system clogged.
2. Engine oil level low.
3. Heat range of spark plug incorrect.
4. Specified engine oil not used.
5. Engine oil contaminated or
deteriorated.
6. Oil filter clogged.
7. Oil feed/injection pump
malfunctions.
8. Load on boat improperly distributed.
9. Water pump/thermostat faulty.
10. Excess water in fuel filter cup.1. Check water intake for restriction.
2. Fill oil tank with specified engine...

5-4
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Trouble Possible Cause Remedy
13. Poor connections or damaged
ignition wiring.
14. Failed ignition parts.
15. Specified engine oil not used.
16. Thermostat faulty or clogged.
17. Air vent screw closed.
18. Fuel pump damaged.
19. Fuel joint connection incorrect.
20. Heat range of spark plug incorrect.13. Check wires for wear or breaks.
Tighten all loose connections.
Replace worn or broken wires.
14. Have serviced by a Yamaha
dealer.
15. Check and replace oil with
specified type.
16. Have serviced by...

5-5
EMN20010
TEMPORARY ACTION IN
EMERGENCY
EMU01492
IMPACT DAMAGE
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The outboard motor can be seriously
damaged by a collision while operating
or trailering. Damage could make the out-
board motor unsafe to operate.
If the outboard motor hits any object in
the water, follow the procedure below.
1) Stop the engine immediately.
2) Inspect the control system and all
components for damage. Also,
inspect the boat for damage.
3) Whether damage is found or not,
return to the nearest harbor slowly
and...

5-6
EMN30210
STARTER WILL NOT OPERATE
If the starter mechanism does not operate
(engine cannot be cranked with the starter),
the engine can be started with an emer-
gency starter rope.
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8Use this procedure only in an emer-
gency and only to return to port for
repairs.
8When the emergency starter rope is
used to start the engine, the start-in-
gear protection device does not oper-
ate. Make sure the transmission is in
neutral. Otherwise, the boat could
unexpectedly start to move, which
could result in an...

5-7
Procedure
1) Remove the top cowling.
2) Remove the flywheel cover by removing
the bolts.
3) Prepare the engine for starting. See
STARTING ENGINE for procedures. Be
sure the engine is in Neutral and that
the lanyard is attached to the engine
stop switch. The main switch must be
on.
NOTE:
8In this case, choke switch will not oper-
ate. Pull out the choke knob when engine
is cold.
8Without setting the main switch to ON, it
is impossible to start the engine.
4) To start the engine with the emergency...

5-8
EMN32110
ENGINE FAILS TO OPERATE
If battery voltage is low or in the unlikely
event of an ignition system malfunction, the
engine speed may become erratic or the
engine may stop. In such a case, discon-
nect the connection on the yellow cord
(emergency circuit) to return to port.
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When the connection is disconnected,
the idling and low speeds are slightly
higher than normal. Use care when start-
ing off or stopping.
1CDI unit
2Yellow cord
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Follow this procedure only in an emer-
gency and just long...

5-9
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218011*
q
218012*
q
905013*e w
EMU19930
LOW OIL LEVEL WARNING
ACTIVATES
If the oil level is allowed to drop too low,
the red segment will appear on the oil
level indicator, the buzzer will sound, and
engine speed will be limited to about
2,000 r/min. If this happens, a reserve
amount of oil can be pumped from the
remote oil tank 3to the engine oil tank 2
using the emergency switch 1.
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Be sure to stop the engine before per-
forming this procedure.
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8If the emergency switch is held up too
long,...