WACKER Group PDI 2, Repair Manual

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Disassembly/Assembly Procedures PD Repair
wc_tx000590gb.fm
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5.12 Testing
See Graphic: wc_gr003464 and wc_gr003465
This procedure requires a vacuum gauge (pn 28755) and a
tachometer.
5.12.1 Check that the mounting hardware for the diaphragm and the valves is
tight.
5.12.2 If the valves are dry, run the pump for a few minutes while adding water
to the pump through the prime plug. Adding water will wet the rubber
gaskets in the valves and provide a better seal while testing.
5.12.3 Reinstall the prime plug.
5.12.4 Start the engine and check the operating speed (rpm) with the
tachometer. Operating speed should be 2700±100 rpm.
5.12.5 Grease the mounting face of the vacuum gauge to ensure a good seal.
Press the gauge over the inlet port.
Note: It is not necessary to keep water in the pump while testing.
Diaphragm pumps do not use a mechanical seal which requires water
in the pump to keep the mechanical seal cool.
5.12.6 Observe the gauge while the pump operates. The gauge reading will
fluctuate slightly as the connecting rod operates the diaphragm. If the
gauge reads 50–55 kPa (15–17 inches Hg) the pump is performing
correctly. If the gauge reads significantly lower than that listed above,
check the diaphragm for cuts or rips like those shown.