Yamaha FZ8NA Service Manual page 383

2. Clean:
• Throttle bodies
ECA39P1703
Observe the following precautions; other-
wise, the throttle bodies may not operate
properly.
• Do not open the throttle valves quickly.
• Do not subject the throttle bodies to
excessive force.
• Clean the throttle bodies with a cloth
which petroleum-based solvent is applied
on.
• Do not use any caustic carburetor clean-
ing solution.
• Do not apply cleaning solvent directly to
any plastic parts, sensors, or seals.
• Do not directly push the throttle valves to
open them.
• Do not touch the synchronizing screws
"a", otherwise the throttle valve synchro-
nization will be affected.
• Do not touch the throttle adjust screw
"b".
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Place the throttle bodies on a flat surface
with the engine side facing up.
b. Install the caps (895-14169-00) onto the
hose fittings "a".
c. Push the lever in the direction shown in the
illustration to hold the throttle valves in the
open position.
EWA14B1022
WARNING
When cleaning the throttle bodies, be care-
ful not to injure yourself on the throttle
valves or other components of the throttle
bodies.
ECA39P1704
Do not open the sub-throttle valves by sup-
plying electrical power to the throttle bod-
ies.
d. Apply a petroleum-based solvent to the
throttle valves and the inside of the throttle
bodies to remove any carbon deposits.
TIP
• Do not allow any petroleum-based solvent to
enter the opening for the injectors.
• Do not apply any petroleum-based solvent to
the portions of the throttle valve shafts
between the throttle bodies.
e. Remove the carbon deposits from the
inside of each throttle body in a downward
direction, from the engine side of the throt-
tle body to the air filter case side.
ECA14B1029
• Do not use a tool, such as a wire brush, to
remove the carbon deposits; otherwise,
the inside of the throttle bodies may be
damaged.
• Do not allow carbon deposits or other for-
eign materials to enter any of the pas-
sages in each throttle body or in the
space between the throttle valve shaft
and the throttle body.
7-10
THROTTLE BODIES