What does cam over mean in air brake system?

Cam over in an air brake system is a condition in which the air pressure in the brake chamber has overcome the force exerted by the return springs, causing the slack adjuster to move to its outermost position. This results in the brake shoes or pads being fully applied, even though there is no longer any air pressure in the brake chamber.

Cam over can occur as a result of a variety of factors, such as:

- A leak in the air line between the brake valve and the brake chamber, or in the return line from the brake chamber.

- Loss of air system pressure due to a compressor failure or a system leak.

- A mechanical problem with the slack adjuster.

- A problem with the brake pedal or parking brake.

Cam over can be a serious safety hazard, as it can cause the brakes to lock up and prevent the vehicle from moving. If you experience cam over, you should immediately pull over to the side of the road and have the brake system inspected by a qualified technician.