Chevrolet 1986 Corvair Owner's Manual page 40

PERIODIC MAINTENANCE AND LUBRICATION
The time or mileage intervals on the following pages
are intended as a general guide for establishing regular
maintenance and lubrication periods for your Corvair.
Sustained heavy duty or high speed operations or oper-
A WORD ABOUT VEHICLE EMISSIONS
All new 1968 Corvairs are certified by the United
States Department of Health, Education and Welfare as
conforming to the requirements of the regulations for
the Control of Air Pollution from New Motor Vehicles
and New Motor Vehicle Engines.
General Motors has developed control systems which
are highly effective in reducing undesirable crankcase
and exhaust emissions. It is very important that the
owner make certain that the engine is serviced regularly
in order to maintain its efficiency and to keep emissions
below maximum allowable limits.
The emission control system on your 1968 Corvair is
relatively easy to maintain, requiring only specific serv-
ices as recommended by Chevrolet. To function properly,
this system must be inspected periodically and engine
tune-up performed at specified intervals by qualified
repairmen. For ready reference, pertinent information
regarding ignition timing and idle speed and fuel mix-
ture specifications is shown on a sticker affixed under
the hood of your vehicle. Following the prescribed main-
37
ation under adverse conditions may necessitate more
frequent servicing. For specific recommendations for con-
ditions under which you use your vehicle, consult your
authorized Chevrolet Dealer.
tenance services will help assure cleaner air and will
provide better running, longer lasting engines for greater
all-around satisfaction, economy and performance.
POSITIVE CRANKCASE VENTILATION (P.C.V')
The Positive Crankcase Ventilation system, which is
standard equipment on your vehicle, prevents emission
of gases from the crankcase. The P .C.V. system connects
the crankcase and intake manifold of the engine and
crankcase gases are returned through this system to the
combustion chamber where they are burned. Periodic
inspection and required servicing of your P.C.V. system
assures a cleaner, better- performing, longer-lasting
engine. A plugged P.C.V. system results in a loss of
crankcase ventilation which can cause condensation of
blow-by gases in the crankcase, resulting in the forma-
tion of acids, sludge build-up and oil dilution. This also
results in an increase in exhaust emissions due to car-
buretor enrichment. Every 12,000 miles or 12 months,
whichever occurs first, the PCV valve should be replaced.