TM 9-2330-373-14 & P
1-7. LOCATION AND DESCRIPTION OF MAJOR COMPONENTS (cont)
(5) AIR RESERVOIR
A metal tank located at center of dolly, near the rear.
Stores compressed air for use in the semi trailer braking
system.
Reservoir (1) is equipped with a drain cock (2) for
draining moisture and releasing air pressure if brakes
are locked.
1. Air reservoir
2. Drain cock
(6) COMPRESSED AIR SUPPLY
Towing vehicle is equipped with an air compressor, air
reservoir, governor for controlling air pressure, air gage,
and safety valve.
Air lines, intervehicular air hoses, air couplings, and
shutoff valves transmit compressed air to semi trailer
brake system.
(7) SERVICE AIR LINE
Extends from air half-coupling (marked SERVICE) along inside of front rail of dolly and along inside of right side rail into
It transmits changes in air pressure which cause relay valve to function.
These changes result from brake being applied in towing vehicle.
(8) EMERGENCY AIR LINE
It extends from air half-coupling (marked EMERGENCY) along inside of dolly left side rail into bottom of relay valve (page
It transmits compressed air to fill air reservoir and to maintain proper air pressure under control of the relay valve.
TA 314697
1-14