Checking The Outboard Motor Mounting Height; Checking The Steering System; Checking The Throttle Cable - Yamaha F4B Service Manual

MNT
2. Check that the throttle operates smoothly
when the throttle grip is turned from the
fully closed position to the fully open
position.
Checking the outboard motor
mounting height
1. Check that the anti-cavitation plate a is
between the bottom of the boat b and a
maximum of 25.0 mm (1.0 in) c below it.
If the mounting height is too high, cavita-
tion will occur and propulsion will
decrease. Besides, the engine speed will
increase abnormally and cause the
engine to overheat. If the mounting
height is too low, water resistance will
increase, which will decrease engine effi-
ciency and performance.
b
TIP:
The optimum mounting height depends on
the combination of the boat and outboard
motor. To determine the optimum mounting
height, test run the outboard motor at differ-
ent heights.
2. Check that the clamp brackets are
secured using the clamp screws.

Checking the steering system

1. Check the steering friction for proper
adjustment.
10-5
Maintenance
c
a
TIP:
• To increase the friction, move the steering
friction adjuster in direction a.
• To decrease the friction, move the steering
friction adjuster in direction b.
2. Check that the
smoothly.
3. Check that there is no interference with
wires or hoses when steering the
outboard motor. (When equipped with
the optional parts)

Checking the throttle cable

1. Turn the throttle grip to the fully closed
position.
2. Check that the stopper a on the throttle
cam a contacts the stopper b on the
bracket b.
3. Turn the throttle grip to the fully open
position.
4. Check that the stopper a on the throttle
cam a contacts the stopper c on the
bracket b.
b
b
b
a
steering operates
a
c
a