Air Brakes - Quiz Sample #3, 15 questions

The brake chamber fills with air pushing the rod out, which moves the _______ ________, which twists the ________ __________.

Brake camshaft and tie rod.

Slack adjuster and tie rod.

Slack adjuster and brake camshaft.

If your vehicle has an alcohol evaporator you should check and fill the alcohol level every day during cold weather.

True

False

To test the air service brakes you should:

Stop the vehicle, put it in low gear, depress the service brake, and then gently pull against the brakes.

Brake firmly while slowly moving backwards.

Brake firmly while slowly moving forward.

In air brake vehicles, the parking brake should be used:

As little as possible.

Any time the vehicle is parked.

To hold your speed when going downhill.

The air compressor governor controls:

When air is pumped into the air storage tanks.

The speed of the air compressor.

Air pressure applied to the brakes.

The most important thing to do when a low air pressure warning comes on is:

Upshift.

Downshift.

Stop and safely park as soon as possible.

If your vehicle has an alcohol evaporator, every day during cold weather you should:

Check and fill the alcohol level.

Change the alcohol from a new bottle.

Check the oil for alcohol content.

Your bus or truck has a dual air brake system. If a low air pressure warning comes on for only one system, what should you do?

Reduce your speed and drive to the nearest garage for repairs.

Reduce your speed and test the remaining system while driving.

Stop and safely park. Continue only after the system is fixed.

It is not safe to drive a vehicle that has brake drums (or discs) with cracks or that are thinner than the manufacturer’s specifications, generally this will be ___ an inch.

1/3

1/4

1/2

Emergency controlled braking is when you:

Apply the brakes as hard as you can without locking the wheels.

Brake as hard as you can, release the brakes when the wheels lock, and put the brakes back on again when the wheels start rolling.

Apply the hand valve for one second, then push hard on the brake pedal.

When performing your air brake leak-down test your engine should be turned off.

True

False

When you apply the brakes, the brake shoes/linings are pressed against the:

Brake drum.

Slack adjuster.

S-cam.

If air pressure is NOT built up fast enough within the correct amount of time:

You should be ready to use your parking brakes to stop.

The alcohol container by be low.

Your air pressure may drop too low during driving.

The proper method of braking when going down a long and/or steep grade after selecting the proper gear, is to brake until your speed is about ___ mile per hour below your “safe” speed, then release your brakes.

In ideal conditions a truck or bus with an air brake going 55 mph would require stopping distance of how many feet?

From 100 to 250 feet.

Less than 100 feet.

More than 300 feet.

It is not safe to drive a vehicle that has brake drums with cracks that are longer than ___ of the width of the friction area.

1/2

1/4

1/32

Why must air tanks be drained?

To drain all the air out of the tank.

To drain moisture and oil out of the tank.

To tell you how much air is in the tanks.

It is possible to have an air leak in one system, which will not affect the other.

True

False

Both systems run off of the same air compressor, so if one air compressor malfunctions you will not be able to build or maintain pressure in either system.

True

False

What are the slack adjusters?

It is the space between the back wheels.

It is an adjusting nut on the backside of the brake drum used for adjusting the brakes.

It is an adjusting nut under the cab to adjust the springs.

How can you check the slack adjuster?

Park on level ground, turn off parking brakes, pull hard on each slack adjuster. It shouldn’t move more than one inch.

Park on level ground, turn off parking brakes, and press brake pedal.

Park on an incline and see if the vehicle rolls.

How can you test the low pressure warning signal?

While the engine is running, step on and off the brake pedal.

Shut off the engine and see if the air pressure leaks down.

Shut off the engine with enough air pressure, turn on the electrical power, and step on and off the brake pedal until the low air pressure warning signal comes on.

What are the maximum leakage rates?

Less than 4 PSI in one minute for single vehicles and less than 8 PSI in one minute for combination vehicles.

Less than 2 PSI in one minute for single vehicles and less than 3 PSI in one minute for combination vehicles.

Less than 6 PSI for all vehicles.

When is it okay to leave your truck unattended without applying parking brakes or chocking the wheels?

If you will only be away from the truck for a few minutes.

Never.

If you are conducting your pre-trip inspection.

If you are away from your vehicle for only a short time you don’t need to use the parking brake.

True

False

If you do not have automatic tank drains, how often should you drain the oil and water from the bottom of compressed air storage tanks?

After every four hours of service.

At the end of each day of driving.

Once a week.

The use of brakes on a long steep downgrade is only a supplement to the braking effect of the engine.

True

False

What factors can cause brakes to fade or fail?

Not pressing the brake pedal hard enough.

Overheating, low air pressure, and not relying on the engine braking effect.

Not taking your foot off the accelerator.

Why should you be in the proper gear before starting down a hill?

So you only have to apply the brake just hard enough to feel a definite slowdown.

So you can coast downhill.

So you can go through the gears on the way down.

If oil and water collects in the air tanks what can happen to the brakes?

The brakes could heat up.

The brakes could fail.

The brakes could lock up.

What is the purpose of an alcohol evaporator?

So you don’t have to drain the air tanks as often.

To have a drink available if you get thirsty.

To reduce the risk of ice in the brake valves and other parts in cold weather.

What is another name for controlled braking?

Steady braking.

Squeeze braking.

Hard braking.

The driver must be able to see a low pressure warning, which comes on before the pressure in the service air tank falls below:

60 PSI

80 PSI

100 PSI

Air Brakes - Quiz Sample #3, 15 questions

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