Air brakes - adjusting in 6 steps
Not like the automobiles and light vehicles that use hydraulic brakes, large vehicles use air brakes. The air brakes provide more braking power. In the case of damage caused to the air brakes, the emergency brakes apply automatically and don’t go off until the solving of the problem.
Follow these steps:
- Block the wheel with chocks
- Turn on the engine and let it work until you have at least 80 pounds of air pressure. Check the air pressure gauge on the dashboard.
- Push the air valve button on the dashboard to release service brakes
- Mark the spot where the push rod comes out of the brake chamber with a piece of chalk. Measure the distance between the marked spot and the place where the rod comes out. It shouldn’t be more than ¾ of an inch.
- Use a wrench and turn the slack adjuster until you feel resistance on the drum. Now reverse ¼ to ½ of a turn. The brake shoes shouldn’t be against the drums. If so back up the slack adjuster a little more.
- Do the same for the other wheels. In the end push back the air valve button. Pull the parking brake and get ready to drive.