How much push rod travel is allowed?
The distance between the mark on the pushrod and the face of the brake chamber is called the free stroke (½ to ¾ of an inch — 12 to 20 mm is a good range). If this distance is more than ¾ of an inch (20 mm), the brakes need adjustment.
What is the pushrod stroke measurement?
Measuring applied pushrod stroke is a reliable method for inspecting brake adjustment. Inspection of brake adjustment at each wheel should be performed with air pressure between 621 and 690 kPa (90 and 100 psi ), the engine shut off and service brakes fully applied and spring brakes must be released.
How much travel should a slack adjuster have?
Automatic slack adjusters are designed to continuously and automatically maintain the brakes in proper adjustment during normal use. However, they must be checked daily to ensure they are maintaining proper push rod travel – less than one in. (25.4 mm) when manually pulled and less than two in.
What determines maximum legal stroke of a brake chamber push rod?
The brake chamber pushrod regulation stroke limits were established to ensure there is sufficient pushrod travel to apply full force to the foundation brake under all operating conditions. The limits are based on the size of the brake chamber and whether the chamber is a standard or long stroke design.
Can a truck driver adjust his own brakes?
Guidance: Yes. A driver may be qualified by the motor carrier to perform a limited number of tasks in connection with the brake system, e.g., inspect and/or adjust the vehicle’s brakes, but not repair them.
Should you adjust automatic slack adjusters?
Because properly installed, operating, and lubricated automatic slack adjusters should never need adjusting after the initial setup, aside from brake relining, Bendix also emphasizes that an out-of-adjustment ASA should never simply be manually adjusted to correct an out-of adjustment brake stroke.
How often should automatic slack adjusters be greased?
every 30,000 miles
It should easily take less than a minute per adjuster,” Gilboy said. “Bendix recommends greasing with an NGLI grade-2 lubricant every 30,000 miles, but you can also make things less complicated by greasing the ASAs every time you do a preventive maintenance inspection.”