AIR BRAKES PRACTICE TEST - MASSACHUSETTS
21.
With a dual air brake system:
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each system shares air tanks.
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each system shares the same lines and hoses.
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each system has its own air tanks, hoses and lines.
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one system is the main braking system while the other is a back-up system.
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22.
Air tanks must be drained completely to:
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remove all moisture and oil.
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pump water and compressor oil into the tanks.
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put alcohol into the air system.
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remove all the air.
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23.
What should you do to test your vehicle's low air pressure warning signal?
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Pump the brakes until the air pressure drops below 80 psi.
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With the key in the "on" or "battery charge" position, rapidly apply and release the foot brake.
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With the engine running, put the vehicle in a forward gear and attempt to drive forward.
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Release the parking brake valve and the tractor protection valve and reduce the air pressure by stepping on and off the brake pedal.
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24.
Some air brake systems have an alcohol evaporator. Checking the alcohol container and filling it up as necessary:
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reduces the risk of ice in air brake valves during cold weather.
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helps keep the engine cool, as well as lubricating it.
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reduces the risk of having an accident due to drowsy driving.
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helps you avoid wheel lock up.
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25.
The wig wag is:
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when your tires might grab unexpectedly and you lose control of your vehicle.
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a noise reduction mechanism.
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a low air pressure warning system.
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a type of rollover.
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