DMV CDL TEST ALREADY GRADED A

DMV CDL TEST ALREADY GRADED A+

You should know that brakes are fading when: Answer- You have to push harder on the brake pedal to control your speed on a down grade.The brake system that applies the use of the brakes when the driver uses the brake

is the: Answer- Service brake system.

The air compressor governor controls: Answer- When air is pumped into the air

tanks.If your truck's air compressor has its own oil supply. When should you first check its oil level? Answer- Before driving.For air brake systems in good conditions the air compressor should start pumping at

about: Answer- 100 psi

If your vehicle has an alcohol evaporator, it is there to: Answer- Reduce the risk of ice in air brake valves in cold weather.Some air brake systems have an alcohol evaporator. What will happen if you don't keep the unit filled with alcohol? Answer- Ice will form in the storage tanks and cause the brakes to fail.

The safety valve is set automatically to reduce pressure at: Answer- 150 psi

The brake pedal in an air brake system: Answer- Controls the air pressure applied to put on the brakes.

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

Answer- The loss of air pressure.The most common type of foundation brake found on heavy vehicle is the: Answer- S-cam drum.

S-cam: Answer- Forces the brakes shoes against the inside of the brake drum.

When the brakes are applied the brake shoes or linings are pressed against the:

Answer- Brake drums or disc.

All air brake equipped vehicles have: Answer- A supply pressure gauge.

The application pressure gauge shows how much air pressure you: Answer- Are

applying to the brakes.Stop light switch: Answer- Turns on the brake lights to warn drivers behind you. 1 / 2

Under normal conditions in order to engage the parking brakes the driver must first: Answer- Make sure the air brake system is fully pressurized.

The braking power of the spring brakes: Answer- Depends on the service brakes

being in adjustment.The parking or emergency brake on trucks and buses can only be held by: Answer- Spring pressure

If the spring brakes are on you should push the brake pedal: Answer- Never

If your truck or bus has dual parking control valves, you can use pressure from a separate tank to: Answer- Release the spring emergency/parking brakes to move a short distance.The driver must be able to see a warning before air pressure in the service air tanks

falls below: Answer- 60 P.S.I.

The most important thing to do when the low air warning comes on: Answer- Stop

and safely park as soon as possible.Your vehicle has a dual air brake system. If a low air pressure warning comes on for

the secondary system; you should: Answer- Bring the vehicle to a safe stop and

continue only when the system is fixed.If your truck has a dual air system and one of the system is low pressure: Answer- Either the front or.rear brakes will not be fully operational.To check the free play of manual slack adjusters on S-cam brakes, you should park

on: Answer- Level ground, chock the wheels, and turn off the parking brakes.

The slack adjuster probably needs to be adjusted if it moves more than, about ___.When you pull hard on it. Answer- 1 inch How should you check that the spring brakes come on when air pressure in the system drops below a certain level: Answer- Park on level ground, chock the wheel release parking brakes when you have enough air pressure, shut the engine off, quickly release and depressed the brake pedal.If your truck has a properly functioning dual air brake system with minimum size air

tanks, the pressure should build from 85 to 100 P.S.I. in: Answer- 45 sec

The air loss rate of a straight truck or bus with the engine off and the air brakes on

should not be more than: Answer- 3 P.S.I. in 1 minute.

If air pressure does not go back to normal in the correct amount of time then:

Answer- The air pressure may drop too low during driving requiring an emergency stop.

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