Can the automatic adjusting arm adjust the clearance manually?

Adjusting arm, also called brake gap adjusting arm, the main function is to adjust the brake gap of the trailer axle brake.

During the braking process of the vehicle, the brake components will continue to wear, the gap between the brake drum and the brake shoe will also increase to varying degrees, resulting in the formation of the pedal is too long, the brake chamber thrust is reduced, resulting in braking lag, braking force decline, wheel deviation, vehicle tail rejection and even brake failure and other problems.

In order to ensure driving safety, maintain the stability of brake pedal travel and the work balance between brakes, brake clearance needs to be adjusted constantly.

The automatic adjusting arm refers to the vehicle adjusting arm that can automatically adjust according to the wear of the brake shoe and the brake drum to ensure that the brake drum and the brake shoe are always in the set optimal gap.

Its working principle is simple, that is, the brake gap value is set at the time of design, if the gap is exceeded in the process of use, the self-adjusting arm will drive the internal one-way clutch when the brake return position to dial the gap value, so that the brake gap is always maintained in the preset range.

Compared with the manual adjusting arm, the automatic adjusting arm has the advantages of good braking gap adjustment consistency, short braking stroke, large torque, stable effect, less air consumption, no manual intervention, etc., as early as more than a decade ago, it has become the standard configuration of heavy vehicles in Europe and America.

So, can the vehicle using the automatic adjusting arm manually adjust the brake clearance? In other words, can the automatic adjusting arm be used as a manual adjusting arm?

If the worm bolt on the self-adjusting arm is turned by the wrench, the brake clearance can be adjusted. However, under normal circumstances, it is not recommended that owners do so, because manual adjustment is very damaging to the mechanical structure inside the self-adjusting arm, and manual adjustment several times may lead to damage to the transmission mechanism.

In addition, some owners ask whether the control arm of the self-adjusting arm can be removed and then used, which is not possible, because the most common cause of damage to the adjusting arm is the locking failure and the role of fixing the gap. If the control arm is removed, the mechanism inside the automatic adjusting arm will not be able to meet the self-locking conditions, and the mechanism inside the self-adjusting arm will rotate when the vehicle braking, and the braking gap will become larger and larger over time, which will eventually lead to brake failure.

It is worth noting that different models of trailer axle matching self-adjusting arm is different, especially its preset brake gap, the owner is best not to modify it without authorization, otherwise it is likely to lead to the brake gap is too large or too small, if you want to replace, it is recommended to confirm the model of self-adjusting arm, it is best to use the original parts.

In terms of maintenance and maintenance, the self-adjusting arm is relatively simple, and it is generally checked every three months, and greasing is added every 20,000 kilometers or every six months.