Shift Cut Control; Over-Revolution Control; Fuel Pump Control - Yamaha F150A Service Manual

Shift cut control

This outboard motor is equipped with a shift cut control system for easier shifting.
This device misfires and retards the ignition of some cylinders to fluctuate the engine speed
instantly when the engine is running from 400 to 2,000 r/min. This allows smooth engagement
and/or disengagement of the dog clutch.
When shifting, the ignition is shut off as shown in the table.
Engine speed
(r/min)
less than 400
Shift cut
switch
Off
On
N/A: No misfire control

Over-revolution control

This outboard motor is equipped with an over-revolution control system to protect the engine.
If the engine speed exceeds 6,200 r/min, the fuel injection is shut off as shown in the table below.
Engine speed (r/min)
6,199 or less
6,200 to 6,300
6,301 to 6,550
6,551 or more

Fuel pump control

The electric fuel pump operates for 3 seconds after the engine start switch is turned on and contin-
ues to operate while the engine is running.
The electric fuel pump stops 1 second after the engine is stopped.
NOTE:
After the engine start switch is turned on, all of the fuel injectors are driven to prevent them from
sticking before the electric fuel pump is driven.
63P3F11
400 to 729
N/A N/A
Retards ignition
N/A
timing
Injected cylinder
#1, #2, #3, and #4
#2 and #3
#2
None
730 to 2,000 2,001 or more
N/A
Misfires the #1
and #4 cylinders,
and then retards
ignition timing
Note
Normal operation
Over-revolution control mode
Technical tips
1
2
N/A
3
N/A
4
5
6
7
8
9
1-20