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Zorluk: OrtaBrake System Components Inspection

A commercial driver is preparing to test the pushrod free play on an air brake system equipped with manual slack adjusters. What action must be taken to ensure an accurate measurement?

  1. A
    Keep the spring parking brakes fully engaged and attempt to pull each slack adjuster toward the brake chamber.
  2. Chock the vehicle wheels on level ground, release the parking brakes, and pull hard on each slack adjuster by hand.Cevap
  3. C
    Fully apply the service brake pedal using a pedal depressor while leaving the parking brakes set.
  4. D
    Drain the air supply tanks completely to zero psi and pull the pushrod while the spring brakes remain applied.

Cevap

Chock the vehicle wheels on level ground, release the parking brakes, and pull hard on each slack adjuster by hand.
To inspect manual slack adjusters on S-cam drum brakes, the vehicle must be parked on level ground with the wheels chocked. Releasing the parking brakes allows the pushrod to relax so the driver can pull hard on the slack adjuster by hand; if it moves more than about one inch where the pushrod attaches, it is out of adjustment and requires service.

Adım Adım Çözüm

1
Secure the vehicle on flat, level ground by placing wheel chocks firmly against the tires.
The vehicle is physically prevented from rolling unexpectedly during the brake check.
Releasing the parking brakes without wheel chocks creates an immediate runaway hazard.
2
Release the parking brakes from inside the cab to remove spring brake tension from the foundation brake linkages.
The brake pushrod returns to its resting position and is free to move manually.
Pushrod free play cannot be physically measured while the spring brakes clamp the pushrod in the extended position.
3
Grasp the slack adjuster with a gloved hand and pull firmly away from the brake chamber at the pushrod connection point.
The pushrod moves outward until the brake shoes contact the brake drum.
Verifies that pushrod travel does not exceed the safe allowable tolerance of approximately 1 inch (2.54 cm).

Anahtar Kavram

Manual slack adjuster pushrod free play inspection protocol and safety prerequisites
Tahmini Süre:1m 0s
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Konular

Brake System Components Inspection

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