TM 9-2320-364-20-32-2201(1) Start engine (TM 9-2320-364-10).(2) Run at idle until air pressure gage reads1254 psi (86128 kPa).(3) Turn OFF ENGINE switch.(4) Check purge valves on air dryers andafter cooler for air leaks or damage.(a) If purge valves are leaking ordamaged, replace valves (Para12-21 and 12-22).(b) If purge valves are not leakingor damaged, valves are OK.VISUAL/AUDIBLE INSPECTIONWear safety goggles when performing leakage tests on valves. Failure to do so may result in serious eye injury due to high pressure air.