Texas CDL Air Brakes Flashcards

Texas CDL Air Brakes Flashcards During normal driving, spring brakes are usually he'd back by what?Air pressure Your vehicle's single brake system needs adjustment if...The compressor cuts out between 70-90 psi.Vehicles with air brakes must have:An air pressure gauge to show the pressure available for braking.A dual air brake system...Has two brake systems and one set of controls.If your vehicle has an alcohol evaporator, everyday during

cold weather you should:

Check and fill the alcohol level.The brake system that applies and releases the brakes

when a driver uses the brake pedal is the:

Service brake system.To check the free play of manual slack adjusters on s-can

brakes you should:

Park on a level ground, chock wheels, and release parking brake.To check the air compressor governor cut in and cut out pressures...

• Run the engine at a fast idle.2. Step in and off the brake

to reduce tank pressure.3. Monitor the air pressure gauge.Air brakes take longer to stop than hydraulic brakes because...It takes longer for the air to flow through the lines.If you must make an emergency stop, you should brake so

that you:

Stay in a straight line and can steer.Air brake systems combine what three different systems?Service brakes, parking brakes and emergency brakes.In air brake vehicles, the parking brakes should be used when?Whenever the vehicle is parked.Fanning air brakes...Decreases the air pressure.What can legally hold a parking or emergency brake in position for a truck, truck tractor or bus?Spring pressure.When driving down a long steep hill you should: Release the brake when you are 5 mph below you safe speed.To determine if slack adjusters need adjustment...Release big the service and parking brakes.The air compressor is connected to the engine through...Gears or a V-belt An air tank is equipped with a drain valve to remove...Water and oil.Slack adjusters...Can be adjusted manually or automatically.An alcohol evaporator does what?Reduces the risk of ice in the air brake valves in cold weather.The governor stops pumping air when it reaches the cut out level, or around...125 psi When he safety valves releases air it means that...1. The pressure has exceeded 150 psi.2. Too much air pressure is in the air compressor.3. Something is wrong, and that you should have it checked by a mechanic.The air compressor governor controls what? When air is pumped into the air tanks.To test low pressure warning...1. Shut of engine.2. Turn on electrical power.3. Step on and off brake pedal to reduce to 60 psi.

Brake drums:1. Are bolted to the wheels.2. Are located at each end of

the vehicles axles.3. Hold the brake shoes and linings.When you apply pressure to the brake pedal, you are...Pushing against a spring and against air pressure to the brakes.If the air compressor should develop a leak, what keeps the air in the tanks?The one way check valve.What makes the total stopping distance for air brakes longer than that for hydraulic brakes?Brake lag distance.An application pressure gauge...Shows how much air pressure you are applying to the brakes.The proper way to go down long grades is to... Apply brakes just hard enough to reduce speed to 5 mph below safe speed then release until back to safe speed and repeat process.If your bus has dual parking control valves it means that

you can use pressure from a separate tank to:

Release the spring brakes to move a short distance.Stab brakingBrake as hard and you can, get off the the breaks when wheels are locked, get back on the brakes when wheels start rolling again.The application pressure gauge shows the driver how

much pressure:

Is being applied to the brakes.You should not use the parking brakes... When the brakes are hot.A fully charged air system typically has ____ psi.125 When testing air leakage rates for combination vehicles(before applying the brake pedal), air brake systems should not lose air faster than...

• psi per minute.

To test service brakes you should...Release the parking brake, move forward slowly and depress brakes.The braking power of the spring brakes:Depends on the adjustment of the service brakes.Why drain water from the compressed air tanks? Water can freeze in cold weather and cause brake failure.Air loss should not be more than ___ with the engine off and brakes released.

• psi per minute

To check the slack adjusters on s-can brakes, you should ...Wear gloves and pull hard on each adjuster.The service brake system...Applies and releases the brakes by issuing the brake pedal under normal driving.With dual air systems, the air pressure should build...From 85 to 100 psi in 45 seconds n The safety valve in the air compressor tank is set to open at?150 psi.When should you avoid using the parking brake? When the brakes are hot.Which type of brake is the most common in commercial vehicles?S-cam brake 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 brakes released.2

When should you drain the air tanks?After every working day.The governor allows the air to star pumping aging when it reaches the cut in level or around...100 psi The first thing you should do when the low air pressure warning comes on?Stop and safely park ASAP.How do you know when your brakes are fading? You have to push harder on the brake pedal to control your speed on a downgrade.The brake pedal in an air brake system does what? Controls the air pressure applied to put on the brakes.The most common type of foundation brakes found on

heavy vehicles is the:

S-can drum Air brake equipped vehicles must have:A supply pressure gauge and warning signal when psi drops below 60.Air brakes should be drained...1. At the end of each working day. 2. To keep sludge from clogging system valves.3. Manually when automatic devices fail.The air compressor governor controls...When the air compressor pumps air into the storage tanks.To test air leakage rate you should...Turn off engine and release the service brake.An emergency brake...Is required on commercial vehicles, must be held by mechanical force, could be activated by loss of air pressure.Compressed air is stored...In the storage tank.Stab braking occurs when you...1. Press on a brake pedal as hard as you can. 2. Release the brakes when the wheels lock up. 3. Apply the brakes when the wheels start rolling.Maximum leakage rates?Single vehicle less than 2 psi per minute. Combination vehicle less than 3 psi per minute.The brake drums or discs...Must not have cracks longer than half the width of the friction area.All vehicles with air brakes are required to have a low pressure warning signal. This could be...A red light, wig wag mechanical arm or a buzzer.If you air compressor stops working...You'll still have pressure left in the tanks.