Power Unit System; Outline - Yamaha F4B Service Manual

Power unit system

Outline

The F4B, F5A, F6C feature an OHV engine with a newly designed cylinder head and cylinder block.
The decompressor is built into the camshaft to facilitate engine cranking with a manual starter.
In addition, a blowby gas reburning system is incorporated to reduce the amount of oil contained in
the blowby gases.
The flywheel magnet, lighting coil, and Rectifier Regulator are available as optional accessories,
and these will enable battery charging. (Optional for European market)
d
c
b
a Valve lifter
b Push rod
c Rocker arm
d Valve
e Rectifier Regulator (optional)
f Lighting coil (optional)
g
f
e
a
Engine control system / Power unit system
g Flywheel magnet (optional)
h Intake silencer
a Decompression actuator
Power unit system
h
a
2-4
0
1
2
3
4
5
6
7
8
9
10
A