GILLIG LOW FLOOR, Руководство по обслуживанию

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Brakes & Wheels
266
SySTEM TESTS
Operation Check
A change in braking characteristics or a low pressure warning may
indicate a malfunction in one of the brake systems. Although the air
brake system may continue to function, the coach should not be operated
until the necessary repairs have been made and both brake systems are
operating normally.
Check the delivery pressure of both circuits using test gauges known to be accurate. Depress the treadle
to several positions between the fully released and fully applied positions and check the delivered pres-
sure on the test gauges to see that it varies equally and proportionately with the movement of the brake
treadle.
Serviceability Test
A slow brake application or release may be caused by a restricted or clogged air line. If this condition is
encountered, disconnect both ends of the suspected line and blow through it to make sure the passage is
clear. Inspect the hose for a partial restriction, such as those caused by dents or kinks. If such a condition
is found, replace the line.
Exhaust Port/Valve Leak Test
1. Apply and hold a high pressure application of more than 80 psi.
2. Coat the exhaust port and body of the application valve with a soap solution. Leakage permitted
is a one inch bubble in three seconds. If leakage is excessive, the valve must be removed and
repaired.
Hose Leak Test
With the air system at normal operating pressure (120 psi) and the brakes applied, coat all hose connec-
tions with a liquid soap solution to check for leakage. No leakage is permissible . Leakage can some-
times be corrected by tightening the connection. If tightening does not correct the leakage, new fittings
or hose assemblies must be installed.