Joyner JNSZ1600DL, Руководство пользователя

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2. Description for PCV system of 480M engine
Fig.132 Fig.133
2.1 Description of PCV system.
The PCV system is a closed system. The leaking air of piston goes to the rear cylinder head cover
from the Crankcase through the PCV hose. PCV valve is connected to the intake manifold. Meantime, a
Ф
15 hose in the front of the valve chamber cover assembly is connected to the guide cover and PCV valve by
the 3-way connector through a hose. The PCV system includes oil baffle assembly, PCV pipe——cylinder
block, PCV hose, PCV valve, 3-way connector, valve chamber cover, connecting hose, and ventilation
hose.
2.2 PCV valve’s function:
Under the low speed condition, the vacuum of intake manifold is very high, which keep the valve
closed, and only a small opening exists to allow the gas pass through. Therefore it won’t change the
mixture rate. Under high speed condition, the vacuum of intake manifold decreases, and the spring forces
the valve to open to allow more gas in the crankcase flow into intake manifold.
The PCV valve is designed to open fully enough to allow the gas exhaust from the crankcase under
high speed or low speed conditions.