How is the governor cut-out pressure checked during the test sequence?

• A.Run the engine at fast idle, watch the gauge climb, and note the pressure where it stops rising (about 120 to 135 psi)
• B.Shut the engine off and fan the brakes
• C.Pull the parking knob and read the gauge
• D.Measure the safety valve with a wrench

Why

With the engine running, pressure rises until the governor unloads the compressor and the needle stops. A stop well below or above the normal range tells the driver the governor needs attention.

Manual topic: Air Brakes - Air Leakage and Brake Tests · From the Air Brakes practice bank (AB-081).

Practice this subject as a full test

More Leakage Rate Standards & Air Tests questions

• For the static leakage test, what are the starting conditions?
• With the engine off and brakes released, what is the maximum allowable leakage rate for a single vehicle?
• With the engine off and brakes released, what is the maximum allowable leakage rate for a combination vehicle?
• For the applied-brake leakage test, what does the driver do after making a full brake application?
• With the brakes fully applied and the engine off, what is the maximum allowable leakage for a single vehicle?