GxT Ferret 54 ENGINE DIAGNOSTIC CENTER - Manual (Page 88)

Probe Tip and Leak Check Cap
LEAK TEST
Leaks in the sample system can allow the
sample to be diluted and cause erroneous
readings. The Leak Test provides a means
of checking the sample system. The system
is comprised of the Sample Hose Assembly,
the water separator filter assembly, the drain
filter and the internal pumps and hoses.
Leaks can occur at any connection in the
sample system. However, the most common
locations are the Sample Hose Assembly
and the filter assembly, if not properly sealed
after replacement of the filters.
To perform the leak test, follow the display
prompts. The end of the sample hose must
be sealed for this test, so be sure the Leak
Test Cap is securely placed over the inlet
holes at the tip of the Sampling Probe. The
pumps will run briefly to create a vacuum in
the system. If a vacuum can not be achieved,
a message will be displayed. Once a vacuum
is created, the pumps will stop and the
vacuum will be monitored for a period of
time. If it is still present at the end of the test,
a message will indicate that the test passed.
If the test fails, disconnect the hose from the
Gas Detector port, plug the port with the leak
test cap and repeat the test. If it passes, then
the leak is in the Sample Hose Assembly.
Otherwise, check the filter bowl and external
hoses for proper seals.
If the test will not pass with the hose
removed, repeat the test with the drain hose
clamped or plugged. Passing the test with
the drain hose plugged indicates that the
drain pump may not be sealing when the
pump turns off. This is not a problem and will
not affect accuracy, since the drain pump is
running when sampling is being performed.
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