Evaporation Control System - Chevrolet Monte Carlo 1971 Owner's Manual

EVAPORATION CONTROL SYSTEM
LIQUID/VAPOR
SEPARATOR
OPERATION: All General Motors passenger cars
and light trucks are equipped with an Evaporation
Control . System. This system is designed to minimize
the escape of fuel vapors to the atmosphere. Included
51
in the system are a special fuel tank, liquid-vapor
separator, carbon canister, canister purge hoses, and
carburetor modifications. Fuel vapors which would
otherwise escape to the atmosphere are directed into
the carbon canister. The carbon adsorbs the vapors
and stores them. The vapor is removed from the
canister during periods of engine operation as mani-
fold vacuum draws the vapors into the engine and
burns them.
NOTE: The General Motors Evaporation Control System is de-
signed
to
control evaporation losses from your car under normal
conditions using 9 lb. Reid Vapor Pressure fuel specified by
Federal and California test requirements. However, if you should
use fuel of abnormally high volatility for existing temperature
conditions, you may detect
a
gasoline odor during or after driv-
ing in heavy traffic. If you find this objectionable, you may prefer
to use
a
lower volatility fuel.
MAINTENANCE: For proper system perform-
ance, periodic canister filter servicing is re-
quired. Every 12 months or 12,000 miles, which-
ever comes first, (more often under dusty con-
ditions) the filter in the base of the canister
should be replaced and the canister inspected.
NOTE: Should it ever be necessary to replace the fuel tank cap,
use only the specified cap.