InspectionQuestion 42 of 60
Before the leak-down (static) tests, to what pressure should the air system be brought?
a.About 20 psi
b.About 45 psi
c.About 60 psi
d.Governor cutout, about 125 psi (fully charged)
Explanation
Before performing the applied and released leak-down tests, the system should be fully charged to about governor cutout pressure (around 125 psi). Starting from full charge gives an accurate measure of how much air leaks out over one minute. Testing from a low pressure would not reveal the true leak rate.
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