Testing Evaporative Emission Control for Range Rover Classic
EMISSION CONTROL
1
FAULT DIAGNOSIS
TESTING EVAPORATIVE EMISSION CONTROL
The following pressure test procedure is intended to
provide a method for ensuring that the system does
not leak excessively and will effectively control
evaporative emissions.
Equipment required.
Nitrogen cylinder (compressed air may be used to
pressure the system when there has NEVER been
fuel present in the fuel or evaporative control
systems).
Water manometer (0 - 30" H2O or more).
Pipework and a "T" piece.
Method.
1. Ensure that there is at least two gallons of fuel in
the petrol tank unless there has never been any
fuel in the system.
2. Disconnect, at the adsorption canister, the pipe
to the vapour separator.
3. Connect this pipe to the nitrogen cylinder and
the water manometer using the "T" piece.
4. Pressurize the system to between 26.5 and 27.5
inches of water, allow the reading to stabilize,
then turn off the nitrogen supply.
5. Measure the pressure drop within a period of 2
minutes 30 seconds. If the drop is greater than
2.5 inches of water the system has failed the
test. Note that a fully sealed system will show a
slight increase in pressure.
6. Should the system fail the test, maintain the
pressure in the system and apply a soap
solution round all the joints and connections until
bubbles appear to reveal the source of the leak.
7. Repeat the test and if successful, dismantle the
test equipment and reconnect the pipe to the
adsorption canister.
