Brakes 204 pretest winter 2025

Excessive heat caused by overuse of the service brakes can cause

• Modulating control valve to wear out.

• The brakes to fade.

• A brake line to split

A typical air brake system is fully charged at

• 75 psi

• 150 psi

• 120 psi

If you do not have an automatic tank drain, When should you drain your air tanks?

• After every four hours of service

• At the end of each working day

• Once a week

Air braking takes more time than hydraulic braking because air

• Brakes use different brake drums.

• Brakes require heavier return springs.

• Takes more time to flow through lines then hydraulic fluid

When you apply the brake pedal, the brake shoes and linings are pressed against the

• Brake drum.

• Slack adjuster.

• S-cam.

During normal driving, spring brakes are usually held back by

• Air pressure.

• Springs.

• Bolts and braces.

What is the first thing you should do if the low air pressure warning comes on?

• Upshift.

• Downshift.

• Stop.

The air compressor should stop pumping air into the air tanks at

• 125 psi

• 100 psi

• 150 psi

Repeatedly pressing and releasing (fanning) the brake pedal may result in

• A buildup of brake air pressure.

• A loss of brake air pressure.

• No change in brake air pressure.

To check the slack adjusters on S-cam drum brakes, you should first

• Stop on level ground and apply the parking brakes.

• Park on level ground, chock the wheels, and release the parking brakes.

• Park on level ground and drain off the air pressure.