TM 5-3825-226-24
AIR SYSTEM AND BRAKES
Tools Needed:
8M2885 Pressure Gauge C0 to
200 psi (0 to 1380 kPa)) 9S5800
Pump Group, and 8F24 Hose
Assembly.
CAUTION
To prevent damage to brake pistons
and seals, do not apply brakes when
brake pads are removed.
AIR PRESSURE GAUGE
TEST GAUGE INSTALLATION
1. Relief valve.
Exhaust the air pressure from reservoir by opening
the bleed valves. Remove relief valve (1) and install a
suitable tee in the relief valve port. Install the relief
valve and the hose and test gauge. Leave the test
gauge installed for all pressure tests.
AIR PRESSURE GAUGE
Start the engine and allow the air pressure to build
up to cutout pressure. Compare the pressure of the
machine's air pressure gauge with that of the test gauge.
The gauge must read within 5 psi (35 kPa) of the
accurate test gauge. If not, install a new gauge.
AIR COMPRESSOR GOVERNOR
Start the engine and let the air pressure to go up to
governor cutout pressure. Note the cutout pressure
shown on the test gauge. Put ON the brakes
(repeatedly) again and again and note the governor cut-
in pressure. If the cutout pressure is not 125 ± 5 psi
(860 ± 35 kPa), and the cut-in pressure 100 to 105 psi
(690 to 725 kPa)adjust the air compressor governor as
follows:
Remove the cover on the governor and loosen the
locknut of the screw for adjustment. Turn the screw as
needed. One counterclockwise turn of the screw raises
the cutout pressure approximately 20 psi (140 kPa).
The cut-in pressure will raise or lower accordingly.
If after the governor is adjusted and it does not
change the cutout pressure, check for a defect in the
compressor unloading valves. If the cutout to cut-in
pressure difference is wrong, check for a defect in the
air compressor governor.
AIR COMPRESSOR
1. Compressor. 2. Governor.
RELIEF VALVE
Remove the air pressure from the reservoir and
remove the relief valve. Connect the valve to a 9S5800
Pump Group and put air pressure to the valve. The
valve should open at 150 psi (1030 kPa). To adjust the
valve, loosen the locknut and turn the screw.
RELIEF VALVE
2-139
