A troubleshooting guide to problems with brake systems.
Optimum braking is essential for truck drivers, but should issues occur, there a number of factors to consider as the source.
Upon inspecting the drum, a crack has been discovered which extends through the entire wall, this condition is caused by excessive heating and cooling of the brake drum during operation.
If this fault is discovered the drum must be replaced immediately. Repeated cracking of the drums may indicate either a brake system fault or driver abuse. If this problem occurs, close attention must be paid to the brake system balance and brake lining friction ratings as specified by the original equipment manufacturer.
Grease stained drums
If this condition is apparent, the brake drum will show discolouration on the braking surface. This condition is normally associated with a faulty lubrication system or improper greasing of the brake cams. Once the source of the contamination has been identified and remedied, thorough cleaning of the components must be carried out, and any contaminated brake linings must be replaced.
Polished Brake Drums
Polished drums can be identified by a mirror-like finish on the braking Surface. This problem can be remedied by lightly sanding both the lining and brake drum surface with some medium grit emery cloth. The brake system should be checked for lightly dragging brakes and the linings should be checked to ensure the correct material is being used. We recommend that the braking surface is sanded each time the linings are replaced.
Broken Mounting Ring
This problem occurs when there is interference between the hub and drum mounting surface, due to incorrect seating of the drum on the hub during installation, a damaged hub, or a build-up of corrosion on the hub. Prior to brake drum replacement the hub should be visually checked and any defects rectified, by either cleaning up the hub or replacing where necessary. If any cracks are identified in the bolt circle or mounting surface the drum must be replaced.
Scored Brake Drum
This problem is indicated by defined grooves in the braking surface of the drum and excessive brake lining wear. These grooves are caused by either the brake linings being completely worn out causing a metal to metal situation, or a foreign body finding its way inside the brake drum area.