Ford Corsar Repair Manual page 389

EVAPORATIVE EMISSION CONTROL SYSTEM
Description
KA24E engine
Throttle chamber
Fuel check valve
uel filler cap with
Carbon canister
: Air
C
: Fuel vapor
The evaporative emission control system is used to reduce
hydrocarbons emitted to the atmosphere from the fuel system.
This reduction of hydrocarbons is accomplished by activated
charcoals in the carbon canister.
The fuel vapor from the sealed fuel tank is led into the canister
which contains activated carbon and the vapor is stored there
when the engine is not running.
The canister retains the fuel vapor until the canister is purged
by the air drawn through the bottom of the canister to the
intake manifold when the engine is running. When the engine
runs at idle, the purge control valve is closed.
Only a small amount of stored vapor flows into the intake
manifold through the constant purge orifice. As the engine
speed increases, and the throttle vacuum increases, the purge
control valve opens and the vapor is sucked into the intake
manifold through both the main purge orifice and the constant
purge orifice.
Carbon Canister Inspection
1. Remove canister.
2. Shake canister
-
there should be no audible sound of carbon
movement.
3. Apply 20-35 kPa of vacuum to the purge valve control port
using a hand pump. Using a piece of hose, it should be poss-
ible to blow low pressure air through the purge hose connec-
tion. Release the vacuum applied to the purge valve control
port, and it should not be possible to blow air through the
purge connection.
4. Using low pressure compressed air (20-35 kPa), blow into the
fuel tank tube connector. Check that air flows freely from the
other tube connectors.