Audi 4.2-liter V8 FSI, Обучение по обслуживанию

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Engine Mechanical
8
Crankcase Ventilation
The crankcase is ventilated through both cylinder heads.
The valve covers incorporate a large settling space.
This space acts as a gravity-type oil separator. A fine oil
separator is connected to the valve covers by means of
plastic hoses.
A control piston, a bypass valve, a two-stage pressure
limiting valve and an oil drain valve are integrated in the
oil separator housing.
After the blow-by gas has passed through the fine
oil separator, the gas flows into the intake manifold
downstream of the throttle valve.
This inlet point is integrated in the coolant circulation
system and heated. This prevents the crankcase breather
from freezing up.
Note:
Modifications after start of production
In both engines, the separated oil flows
into the crankcase through the cover in the
inner V, adjacent the crankcase breather
(no longer through the chain housing).
In the Audi Q7 engine, the crankcase is
vented through a single chamber, i.e.,
via bank 2 only. Better icing protection is
achieved in this way.
377_009
Breather Pipe Heater
Crankcase Breather System
Breather Pipe
Bypass Valve
Fine Oil Separator
Pressure Limiting Valve
Non-return Valve
(crankcase breather)