spark plugs replace YAMAHA SUPERJET 2008 Owners Manual

Maintenance and care
51
EJU33820Periodic maintenance chart
The following chart gives general guidelines for periodic maintenance. However, maintenance
may need to be performed more frequently depending on your operating conditions.
This “” mark indicates maintenance that you may do yourself.
This “” mark indicates work to be done by a Yamaha dealer.
Item OperationInitial Thereafter every
Page 10
hours50
hours100
hours100
hours200
hours
6
months12
months12
months24
months
Spark plugsCheck, clean, adjust 57
Lubrication pointsLubricate 58
Intermediate hous-
ingLubricate 58
Fuel systemCheck 53
Fuel filterCheck, clean, replace 53
Fuel tankCheck, clean 53
CarburetorCheck, adjust 61
Trolling speedCheck, adjust 61
Carburetor throt-
tle shaftCheck—
Cooling water pas-
sagesFlush
*46
Bilge strainerClean—
ImpellerCheck—
Jet thrust nozzle
angleCheck, adjust 53
Handlebar pivot
shaftCheck—
Steering frictionCheck, adjust 54
Throttle cableCheck, adjust 56
Choke cableCheck, adjust 59
BatteryCheck, charge 60
Rubber couplingCheck—
Engine mountCheck—
UF2F70E0.book Page 51 Tuesday, April 17, 2007 9:56 AM

Maintenance and care
57
(4) Hold the adjuster with one wrench while
tightening the locknut with another
wrench.
(5) Install the handlebar cover and the four
screws.
EJU34371Cleaning and adjusting the spark
plugs
WARNING
EWJ00350
Be careful not to damage the insulator
when removing or installing a spark plug.
A damaged insulator could allow sparks to
escape, which could result in a fire or ex-
plosion.
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. Have a
Yamaha dealer service the watercraft.
Remove and inspect the spark plugs periodi-
cally; heat and deposits will cause the spark
plugs to slowly break down and erode. If elec-
trode erosion becomes excessive, or if carbon
and other deposits are excessive, replace the
spark plug with the specified plug.Measure the spark plug gap with a wire thick-
ness gauge. Replace the spark plugs or ad-
just the gap to specification if necessary.
To install a spark plug:(1) Clean the gasket surface.
(2) Wipe any dirt from the threads of the
spark plug.
(3) Install the spark plug, and then tighten it
to the specified torque.
(4) Install the spark plug cap.
NOTE:

Wipe off any water on the spark plug or in-
side the spark plug cap before installing the
cap. Push the spark plug cap down until it is
securely installed.

If a torque wrench is not available when you
are installing a spark plug, a good estimate
of the correct torque is 1/4 turn to 1/2 turn
past finger tight using the spark plug
wrench included in the tool kit. Have the
spark plug adjusted to the correct torque
with a torque wrench as soon as possible.
Throttle lever free play:
7.0–10.0 mm (0.28–0.39 in)
Specified spark plug:
BR7HS
1Spark plug gap
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
Spark plug tightening torque:
25.0 Nm (18.4 ft-lb) (2.55 kgf-m)
UF2F70E0.book Page 57 Tuesday, April 17, 2007 9:56 AM