Installation Instructions

18. Emission Control System
18-8
Positive Crankcase Ventilation System (P.C.V.)
1. Construction
2. Principle of operation:
y Install a separated chamber on cylinder head, and suck the blow-by gas to the fuel vapor separator
by engine vacuum.
y Drill a hole in the air cleaner and install a vapor separator, so that blow-by from crankcase will flow
through a cylinder check valve and then separated by the separator.
y The separated vapor will be sucked into combustion chamber by engine negative pressure to be
burned again instead of discharging into atmosphere. Drain liquidized fuel in the drain pipe
periodically.
3. Service Methods
Visual check:
y Remove drain plug to drain the fuel when fuel level on the drain pipe reaches 80 % full.
y Check connecting hose for damage and looseness.
Cylinder
head
Carburetor
Flesh air
Exhaust pipe
Air filter
Fuel vapor separator
Crankcase
Blow-by pipe
Piston
Flesh air
Mixture gas
Blow-by
Engine oil
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