TM 5-2330-325-14&P
4-51.
SPRING BRAKE CONTROL VALVE REPLACEMENT (Continued).
c.
Operating Test.
(1)
With gladhands connected to towing vehicle, apply brakes. Check to see that brakes of all
semitrailer wheels apply properly.
(2)
Release brakes. Check to see that each brake releases properly.
(3)
With brake system fully pressurized, close shutoff cock on emergency hose in towing vehicle.
Disconnect glandhands tagged EMERGENCY to towing vehicle. Make sure semitrailer
brakes apply automatically.
(4)
Connect gladhands tagged EMERGENCY to towing vehicle. Open shutoff valve cock in
towing vehicle. Check to see that brakes release automatically.
d.
Leakage Test.
(1)
With air system connected, apply a solution of detergent and water to flanges holding
diaphragm in spring brake chamber, and to gladhands tagged SERVICE. No leakage is
permitted. Tighten nuts on flanges and coupling on gladhands as required.
(2)
With brake system fully pressureized, close shutoff cock on emergency line in towing vehicle.
Disconnect gladhands tagged EMERGENCY from towing vehicle. Make sure semitrailer
brakes apply automatically. Coat spring brake control valve exhaust port with a solution of
detergent and water.
(3)
Leakage must not exceed a one-inch (2.5 cm) bubble in three seconds. If excess leakage is
found, replace spring brake control valve.
FOLLOW-ON TASKS:
None.
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