Maintenance
EMU28956
Cleaning and adjusting spark plug
The spark plug is an important engine compo-
nent and is easy to inspect. The condition of
the spark plug can indicate something about
the condition of the engine. For example, if the
center electrode porcelain is very white, this
could indicate an intake air leak or carburetion
problem in that cylinder. Do not attempt to di-
agnose any problems yourself. Instead, take
the outboard motor to a Yamaha dealer. You
should periodically remove and inspect the
spark plug because heat and deposits will
cause the spark plug to slowly break down
and erode.
1.
2.
3.
Spark plug gap
Spark plug part number
Spark plug I.D. mark (NGK)
Spark plug gap:
0.9–1.0 mm (0.035–0.039 in)
1.
Remove the spark plug caps from the
spark plugs.
4.
When fitting the plug, wipe off any dirt
from the threads, and then screw it in to
the correct torque.
2.
Remove the spark plug. If electrode ero-
sion becomes excessive, or if carbon and
other deposits are excessive, you should
replace the spark plug with another of the
correct type. WARNING! When remov-
ing or installing a spark plug, be care-
ful not to damage the insulator. A
Spark plug torque:
25.0
Nm (2.55 kgf-m, 18.4 ft-lb)
TIP:
damaged insulator could allow exter- If a torque-wrench is not available when you
nal sparks, which could lead to explo- are fitting a spark plug, a good estimate of the
sion or fire.
[EWM00561]
correct torque is 1/4 to 1/2 a turn past finger-
tight. Have the spark plug adjusted to the cor-
rect torque as soon as possible with a torque-
Standard spark plug:
B7HS-10
wrench.
EMU37450
3.
Be sure to use the specified spark plug,
otherwise the engine may not operate
properly. Before fitting the spark plug,
measure the electrode gap with a wire
thickness gauge; replace it if out of spec-
ification.
Checking fuel filter
Check the fuel filter periodically. If any water
or foreign matter is found in the filter, clean or
replace it. For cleaning or replacement of the
fuel filter, consult your Yamaha dealer.
EMU29043
Inspecting idling speed
EWM00451
WARNING
q
Do not touch or remove electrical parts
when starting or during operation.
48
| Categories | Yamaha Outboard Manuals |
|---|---|
| Document Type | Boat Motor Manual Free Download. Marine Operator's Boating Guide. |
| Tags | Yamaha 15, Yamaha 9 |
| Model Year | 2008 |
| Download File |
|
| Language | English |
| Product Brand | Yamaha Motor. Yamaha Motor Corporation, USA - Support Customer Relations for US: 1-800-962-7926
Yamaha Boats: 1-800-962-7926 Yamaha Outboard Customer Relations: 1-866-894-1626 , Yamaha Outboard |
| Document File Type | |
| Publisher | yamaha-motor.com |
| Wikipedia's Page | Yamaha Motor Company |
| Copyright | Attribution Non-commercial |
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