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Daily inspection test
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3. Pushrod stroke of any brake exceeds the adjustment limit

You must know the proper method for checking brake pushrod stroke, and that a vehicle has this major defect when the pushrod stroke of any brake is longer than the prescribed limit.

Certain vehicles do not provide access to measure the applied pushrod stroke (buses, low-slung vehicles and those with obstructive fairing or body panels, or vehicles equipped with air disk brakes). In such cases, the exami­nation is conducted verbally.

Here are the steps you must take to measure applied pushrod stroke.

    1. Secure the vehicle with wheel chocks or blocks.
    2. Ensure air pressure is above 621 kPa (90 psi) and release the spring brakes.
    3. Select one of the following methods:
      • Method 1: Mark the pushrod at the brake chamber or at a suitable fixed reference point. (Use chalk, soapstone, marker or other similar instrument. Marks must be narrow and precise.)
      • Method 2: Measure the released position of the pushrod. (Measure and note the distance from a point on the pushrod to a suitable fixed point at the brake chamber. This is measurement number 1.)
    4. Raise or lower the air pressure by running the engine or pumping the brake pedal until both the primary and secondary air-tank gauges display 621 to 690 kPa (90 to 100 psi).
    5. Shut off the engine.
    6. Press and hold the brake pedal in the fully applied position, and use a suitable means to hold the brakes applied in order to leave the cab and inspect them.
    7. Determine the applied pushrod stroke. (Continue to use the previously selected method.)
      • Method 1: Measure the distance from the brake chamber or fixed reference point to the mark on the pushrod.
      • Method 2: Measure the applied position of the pushrod. (Re-measure and note the distance from the previously selected point on the pushrod to the previously selected fixed point at the brake chamber. This is measurement number 2.) Subtract measurement 1 from measurement 2 to calculate the applied pushrod stroke measurement.
    8. Determine the number size (such as 16, 20, 24 or 30) and type (such as standard or long-stroke) of the brake chamber.
    9. Determine the adjustment limit for the brake chamber.
    10. Compare the applied pushrod stroke to the applicable adjustment limit and identify any brake that exceeds the adjustment limit as defective.