DSL 204 Brakes MIDTERM

Which of the following statements is correct?

• a. A left-hand S-cam cam shaft is located on the driver's side of the vehicle and turns clockwise to apply brakes.

• b. A left-hand S-cam cam shaft is located on the driver's side of the vehicle and turns counterclockwise to apply brakes.

• c. A right-hand S-cam shaft is located on the driver's side of the vehicle and turns counterclockwise to apply brakes.

• d. A right-hand S-cam shaft is located on the driver's side of the vehicle and turns clockwise to release brakes.

What is the effect on the brake application force if an automatic slack adjuster with a longer arm is installed?

Select one:

• a. Application force increases, and brake chamber stroke length remains the same

• b. Application force decreases, but brake stroke length increases

• c. Application force increases, but brake stroke length decreases

• d. Application force increases, and brake stroke length increases

Which of the following describes the relationship between braking force and vehicle speed?

Select one:

• a.Braking force is directly proportional to vehicle speed.

• b.Doubling vehicle speed requires two times more braking force.

• c.Doubling vehicle speed requires four times more braking force.

• d.Doubling vehicle speed requires eight times more braking force.

Consider a bus with air brakes operating at 5280 ft (1609 m) altitude. What effect does the lower atmospheric pressure have on the brake system operation?

Select one:

• a. Maximum air tank pressure is lower.

• b.Brake application force is lowered.

• c. There is no change on air system pressure or application force.

• d. The transmission speed of air through brake lines is reduced.

While recommending repairs to a truck with oil contaminated brake lining caused by a leaking wheel seal, Technician A says the lining should be replaced, not just cleaned, on just the contaminated wheel end. Technician B says that the brake lining should be replaced on both sides of the same axle with the contaminated lining. Who is correct?

Select one:

• Tech A

• Tech B

• Both

• Neither

Clocking a service brake chamber - Reference Bendix Brake school: When clocking the service brake chamber, it is recommended that you do what?

• a. Remove the chamber

• b. Clamp the chamber in a vice

• c. Charge the air system to cut out pressure

• d. Secure the pushrod with vice grips or a similar device to hold it in place

Clocking a service brake chamber - Reference Bendix Brake school: Once the cover is removed and free it should be what?

• a. Rotated in the direction needed to align with the air supply line

• b. Disposed of because a new cover will be needed

• c. Inverted so that there is a new surface to mount the diaphragm

• d. None of these are correct

S-Cam Brake shoe Removal and Installation: The slack adjuster should be backed off until the​ ​ .

Select one:​ (a)  

• Rollers are down in the S-Cam pockets.
• Drum can be removed
• Chamber pushrod is at full stroke
• Clevis pin can be removed

S-Cam Brake shoe Removal and Installation: The purpose of the retaining spring is to​ ​ .

Select one:​ ​ (a)   ​

• Hold the shoes to the anchor pin
• Anchor the slack adjuster to the S-Cam
• Release the spring brake chamber

What is the correct assembly order of an S-Cam drum brake?

Select one:

• Install drum, replace shoes, adjust brake

• b. Replace shoes, adjust brake, install drum

• c. Replace shoes, install drum, adjust brake

• d. Adjust brake, install drum, replace shoes