Unit F: Air Brakes Flashcards
When referring to the primary brake circuit of an air brake ABS system, the ABS modulator valve can be located between the relay valve and the brake chamber.
True or False
True
A brake chamber generating 2000 lb of force on a slack adjuster 6 inches in length will cause _____ lb-in of torque.
12,000 in-lb
As of ____, ABS became mandatory on most new air-braked heavy-duty trucks.
1998
A brake chamber generating 2200 lb of force on a slack adjuster 6 inches in length will cause ____ lb-in of torque.
13,200
The dual-circuit brake valve controls the primary and ____ service circuits.
Secondary
Which ABS component is connected to the ECU?
Speed Sensor
Removing material from the inside of a brake drum by machining will improve the heat dissipation of the brake drum.
True or False
False
The service line glad-hands are often colour coded ____.
Blue
When referring to an air brake ABS system, the ECU monitors the ____ of each wheel.
Rotational speed
The gap between the ABS speed sensor and tone ring should be ____.
As small as possible
The maximum ____ diameter of a brake drum is stamped to the brake drum.
Inside
The maximum belt deflection of an air brake system air compressor is __. (inches or mm)
1/2 to 3/4 inch or 12 to 18 mm
A standard relay valve will have a crack pressure of ____ psi.
2 to 4
The loss of air pressure on the supply line of a pre- 121 trailer will result in ____.
Dynamiting of the trailer brakes
Which of the following would be an output of the ECU? Tone ring Speed sensor Brake modulator valve Brake lights
Brake modulation valve
