Chevrolet 1963 Corvette, Руководство по ремонту и настройке

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Emission Controls
and Fuel System
EMISSION CONTROLS
Positive Crankcase Ventilation
(PCV)
In this system, crankcase vapors are drawn
into the intake manifold to be burned in the
combustion chambers; instead of merely
venting the crankcase vapors into the atmo-
sphere. An added benefit to engines equipped
with this system is that the engine oil will tend
to stay cleaner for a longer period of time;
therefore, if you notice the oil in your engine
becomes dirty very easily, check the func-
tioning of the PCV valve. The valve should
rattle when shaken, indicating that sludge has
not stopped operation of the valve, and the
PCV line to the carburetor or the intake man-
ifold must be clear. Engines which use a PCV
system are calibrated to run richer, to com-
pensate for the added air which accompanies
the crankcase vapors to the combustion
chambers. If the PCV valve or line is clogged,
the engine idle will tend to be rough due to
the excessively rich mixture. Maintenance is
covered in Chapter 1.
Air Injection Reactor (AIR)
Two different systems of air injection have
been used on the Corvette. The system used
up to and including 1980 (except 1980 Calif.)
consists basically of the following compo-
nents:
a. Air injection pump—Draws fresh, out
side air into the pump, pressurizes the air,
then delivers the air to the remaining system
components.
b. Diverter valve (sometimes called an
anti-backfire valve)—Receives pressurized air
from the air injection pump. The diverter
valve is controlled by manifold vacuum. Dur
ing deceleration, manifold vacuum increases
sharply. This vacuum increase causes the di
verter valve to divert the air from the air in
jection pump to the atmosphere, thereby
preventing backfiring through the exhaust
system. If vacuum is evident at the diverter
AIR INJECTION PUMP
CHECK VALVE
KEY TO PCV SYSTEM I
<==> F=FILTEREDAI »«4 B =
BLOW BY GASES
»4 F + B
Dm* COMBUSTIBLE MIXTURES* ?'H
Schematic of the PCV system
DIVERTER VALVE
CHECK VALVE
Typical 350 cu In. engine A.I.R. system compo-
nents