Oerlikon S12 Series, Service Manual

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6
The Leak Test The purpose of a leak test is to make sure the unit is airtight. To
perform a leak test use the leak test fixture from the table below. If
the tool is not available, the gearbox must be sealed to perform the
test. This can be accomplished by assembling the sealed input
device onto the gearbox at the input end and replace one of the oil
plugs with an air chuck. DO NOT EXCEED 10 PSI PRESSURE
DURING THE LEAK TEST. Higher pressure will create a false
sealing effect in assemblies with lip-seals.
The unit has a leak if the
pressure gauge reading on your leak check fitting starts to fall after
the gearbox has been pressurized and allowed to equalize. Leaks
will most likely occur at the pipe plugs, the main seal or wherever
o-rings or gaskets are located. The exact location of a leak can
usually be detected by brushing a soap and water solution around
the main seal and where the o-rings or gaskets meet on the exterior
of the unit and then checking for air bubbles. If a leak is detected in
a seal, o-ring, gasket, the part must be replaced and the unit
rechecked. Leak test at 10 psi for 20 minutes.
Model code Leak Test Tool
S12Ax44xx
T220225
S12Ax55xx
T173814