Urrea 2012 Manual De Usuario Y Garantía página 10

E N G L I S H
temperature but not running, disconnect the
vacuum line to the diaphragm module. Connect
the testvac pump and apply approximately
15inHg and allow to sit for 30 seconds. Not
drop in gauge reading should be noted. With
the vacuum still applied ensure that the choke
butterfly is pulled to the fully open position.
Example 2: Testing vacuum operated
carburettor secondary barrel
With the engine at normal operating temperature
but not running, remove the vacuum line from
the secondary diaphragm module. Attach the
test vac pum, hold the throltle and secondary
air valve flaps open. Operate the hand pump
whilst observing free and easy opening of the
secondary throttle butterfly.
Testing fuel injection pressure regulator
Multi point fuel injection rail pressure must vary
to suit changing engine loads and fuel delivery
requirements. This is done using a vacuum
operated regulator which is connected to the
engine manifold vacuum to sense the vaying
loads.
To test the fuel rail pressure, a gauge is attached
to the rail, then engine loads must be created to
vary engine manifold vacuum.
Simply remove and block off the vacuum supply
line to the pressure regulator, connect and
operate the vacuum pump to simulate vacuum
pressures in accordance with the manufacturers
specifications and note variation in fuel pressure
reading.
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Testing emission control exhaust gas
Recirculation valves (EGR)
Start engine and run at idle until normal
operating temperature is reached. Remove the
vacuum line from the EGR valve and attach the
testvac vacuum pump.
Operate the hand pump to apply approximately
15 inHg. If the EGR valve is working correctly
the engine idle will become rough. If the idle
remains unchanged the valve is possibly seized
in the closed position. If the vacuum is not held,
the diaphragm in the valve is fractured.
Testing one way valves
Many vacuum operated circuits use in line one
way valves to apply vacuum in one direction
only. To test the function of the valve remove
it from the circuit. Attach the testvac vacuum
pump and operate to apply vacuum. In one
direction the valve must hold vacuum and in the
opposite direction it must not.
Testing electrically
solenoids
Electrically operated vacuum solenoids are
commonly used in control circuits for air
conditioning / ventilation systems, emission
control systems, idle step up systems etc., and
testing the function of these when using testvac
is extremely simple.
operated vacuum