Vehicle InspectionQuestion 16 of 120
You start the engine with the air tanks nearly empty and watch the gauge. On a dual air system, roughly how quickly should pressure build from 85 to 100 psi at operating rpm?
a.Within 5 seconds
b.Within 15 seconds
c.Within 3 minutes
d.Within about 45 seconds
Explanation
A properly working dual air system should build from 85 to 100 psi in about 45 seconds at operating rpm. Five or fifteen seconds is unrealistically fast for a truck compressor, and three minutes indicates a weak compressor or a leak that must be repaired.
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