Air Break Test

Question 1

No trucks should ever be operated with less than ________in primary or
secondary air tanks. Let pressure build before moving any trucks or equipment.

Answer 1

100 PSI

Question 2

1) Once vehicle is properly chocked on flat ground start engine and build air
pressure till system reaches governor cut off

Answer 2

(120 – 140 PSI)

Question 3

2) Shut engine off, leave key in on position, and release parking brake (push in
knob) let air pressure settle for a few seconds then monitor both primary and
secondary air pressure gauges. Both systems should hold pressure for _____
seconds with no more than ______PSI pressure drop. If primary or secondary air
systems drop more than _____ PSI within _____ seconds unit is out of service

Answer 3

60 seconds, 2 psi

Question 4

3) With system still at governor cut off pressure (120 – 140 PSI), engine off, Key
on. Fully apply foot brake and hold for 60 seconds. Air pressure will drop at
first then should settle. After air pressure settles start timer and monitor air
pressures. Both primary and secondary air systems should hold air pressure
for ______ seconds with no more than _____ PSI air drop. If primary or secondary air
systems drop more than _____PSI in _______seconds unit is out of service.

Answer 4

60 seconds, 3 psi

Question 5

4) Release foot brake then turn ignition on with engine off. Make sure parking
brake is still released (knob pushed in). Cycle foot brake until low air light and
low air alarm comes on. Both low air light and low air alarm should come on
before ______ in either primary or secondary air tank. If light or alarm doesn’t
come on before _______ unit is out of service

Answer 5

60 psi

Question 6

5) With engine off, parking brake dash valve still released (knob pushed in)
monitor air pressures then continue to cycle foot brake unit parking brake
dash valve pops out. Valve should pop out between ________________PSI

Answer 6

20 – 45

Question 7

6) Start engine and let air pressure build with engine in high idle. Air pressure
should build from _____________ within____________ seconds in high idle. If unit
does not build pressure from_________PSI within _____ seconds the unit is
out of service.

Answer 7

85 PSI to 100 PSI, 45 seconds

Question 8

7) Let system continue to build unit governor pressure is achieved (air pop off
sound). System should build air pressure of ___________. If system
doesn’t build air pressure to ______________ unit is out of service.

Answer 8

120 PSI to 140 PSI