Questions and Answers
The parking or emergency brake on a heavy vehicle can only be held in position by something that cannot leak away, like:
A straight truck or bus air brake system should not leak at a rate of more than __ psi per minute with the engine off and the brake released.
If low air pressure warning comes on for the secondary system or for one system, you should:
If your vehicle has an alcohol evaporator, it is there to:
Signup and view all the answers
Air braking takes more time than hydraulic brakes because air:
Signup and view all the answers
The brake pedal in an air brake system:
Signup and view all the answers
With air brake vehicles, the parking brakes should be used:
Signup and view all the answers
For emergency stab braking, you should:
Signup and view all the answers
If your truck or bus has dual parking control valves, you can use pressure from a separate tank to:
Signup and view all the answers
Modern air brake systems combine three different systems. They are the service, parking, and the _________ brakes.
Signup and view all the answers
To check the free play of the manual slack adjusters on the S-cam brakes, you should park on:
Signup and view all the answers
Of the choices below, the first thing to do when a low air pressure warning comes on is:
Signup and view all the answers
The air compressor governor controls:
Signup and view all the answers
Study Notes
Air Brake System Key Facts
- Spring pressure is used to hold the parking or emergency brake in position on heavy vehicles.
- A straight truck or bus should not leak more than 3 psi per minute when the engine is off and brakes are released.
- Upon low air pressure warning in a dual air brake system, stop safely and do not drive until fixed.
Alcohol Evaporator and Air Brake Operation
- An alcohol evaporator reduces the risk of ice forming in air brake valves during cold weather.
- Air braking is slower than hydraulic braking due to the time needed for air to travel through the system.
- The brake pedal in an air brake system controls the air pressure that applies the brakes.
Parking Brake Usage
- Use parking brakes whenever leaving a vehicle unattended to prevent rolling.
Emergency and Stab Braking Techniques
- For emergency stab braking, apply maximum pressure, release when wheels lock, and reapply when wheels begin to roll.
Dual Control and Emergency Braking
- Dual parking control valves allow use of pressure from a separate tank to release spring emergency/parking brakes temporarily.
- Modern air brake systems consist of service, parking, and emergency brakes.
Slack Adjusters and Low Air Pressure Response
- To check manual slack adjusters, use level ground, chock the wheels, and turn off parking brakes.
- The first response when a low air pressure warning activates is to stop and safely park the vehicle.
Air Compressor Governor Function
- The air compressor governor regulates when air is pumped into the air tanks to maintain proper pressure in the braking system.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge on air brake systems, including key facts about parking brakes, emergency braking techniques, and the role of the alcohol evaporator in cold weather. This quiz covers essential information for heavy vehicle operation and safety. Ensure you're well-prepared for real-world applications and standards in air brake functionality.
