Vehicle InspectionQuestion 27 of 120
Why must you drain moisture from the air tanks or verify that the automatic drain valves are working?
a.Water increases the governor cut-out pressure
b.Water and oil in the tanks can freeze in cold weather and damage the system, reducing braking ability
c.Draining is only needed on trailers, not tractors
d.It keeps the compressor from over-charging the batteries
Explanation
Compressed air carries moisture and oil that collect in the tanks, where they can freeze and block valves or corrode components until braking is compromised. Draining does not affect governor settings or the charging system, and it applies to tanks on every unit.
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