How does automatic slack adjusters work?
When the brake is applied, a rod pushes out on the slack adjuster, which then turns the S-cam to force the brake shoes apart to apply the friction necessary to slow the truck. The automatic slack adjuster is designed to compensate for brake lining and drum wear to maintain a constant actuator stroke.
What is the function of slack adjuster?
The Automatic Slack Adjuster (ASA) is a vital part of the foundation brake. It acts as a lever, forming the connection between the actuator and the camshaft. The function of the ASA is to compensate for wear in both brake lining and brake drum while maintaining a constant stroke of the actuator.
What is the difference between manual and automatic slack adjusters?
Automatic slack adjusters perform the same function as the manual slack adjuster, except that it automatically adjusts for lining wear. It does not require periodic manual adjustment, however the slack adjuster does provide for manual adjustment if necessary.
How do manual slack adjusters work?
It is mounted on the S-cam shaft. One end is connected to the brake chambers’ pushrod. So, when the driver presses down on the brake pedal, air is forced into the brake chamber and shoves the push rod out. Once this happens, it rotates the slack adjuster which forces the brake shoes out.
Are all slack adjusters automatic?
After 1994, all vehicles made have automatic slack adjusters installed. However, if you are driving a vehicle that predates this regulation, manual adjusters require fine-tuning.
What are the different slack adjusters?
Slack adjusters are available in two types: manual slack adjusters and automatic slack adjusters. Manual slack adjusters compensate for the distance in the brake linkage by adjustments made with a wrench. Automatic slack adjusters remove the slack in the brake linkage without the need for manual adjustment.
Are automatic slack adjusters mandatory?
Automatic slack adjusters, or ASAs, also called automatic brake adjusters, have been required for trucks and tractors since 1994 and trailers since 1995. Drivers have a duty to inspect brakes for proper adjustment during a pre-trip inspection.