08. Modern air brake systems combine three different systems. They are the service, parking, and the _____ brakes.
a. emergency.
b. foot.
c. S-cam.
d. drum.
09. To check the free play of manual slack adjusters on S-cam brakes, you should park on:
a. level ground with the parking brake, then apply the service brake.
b. level ground, chock the wheels, and turn off the parking brakes.
c. level ground and drain off air pressure before adjusting.
d. a slight grade, release the parking brakes, apply the service brakes, and check for vehicle movement.
10. Of the choices below, the first thing to do when a low air pressure warning comes on is:
a. stop and safely park as soon as possible.
b. shift to the next higher gear.
c. adjust the brake pedal for more travel.
d. open the air supply control valve.
11. The air compressor governor controls:
a. the speed of the air compressor.
b. when the brake chambers release pressure.
c. air pressure applied to the brakes.
d. when air is pumped into the air tanks.
12. The braking power of the spring brakes:
a. is not affected by the condition of the service brakes.
b. can only be tested by highly trained brake service people.
c. depends on the service brakes being in adjustment.
d. increases when the service brakes are hot.
13. All air brake equipped vehicles have:
a. at least one brake heater.
b. a hydraulic system, in case the air system fails.
c. a supply pressure gauge.
d. an air use gauge.
14. If you must make an emergency stop, brake so you:
a. can steer hard while braking hard.
b. use the full power of the brakes and lock them.
c. can steer and your vehicle stays in a straight line.
d. use the hand brake first.
15. The application pressure gauge shows how much air pressure you:
a. have used in this trip.
b. have in the air tanks.
c. are applying to the brakes.
d. None of the above.
Page 2 answers: (8)a (9)b (10)a (11)d (12)c (13)c (14)c (15)c
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