With the onset of Autumn and Winter, garages have a key part to play in ensuring cars are fit for purpose.
The most common failure during this season is of course the battery, and it goes without saying, frozen coolant and screen wash due to insufficient additive, or out of date antifreeze.
With the roads clogged with ice, it is even more important that the brakes are operating efficiently and more importantly, evenly across an axle. Locking up of a front or rear wheel can lead to a nasty spin and accident. Salt and grit can also lead to issues with corrosion.
A visual inspection of the mechanical and hydraulic parts is the first step, looking for in particular leaking, cracking and wear of all associated parts.
Having completed the visual checks, now check the physical operation of the caliper, in particular, the free sliding action of the guide bolts in the carrier. The piston should push its pad into contact with the disc, and the carrier should pull the other pad into contact.
If this fails to happen, and there are any signs of corrosion or damage, dismantle the caliper and remove the pads. Take the carrier, and clean using brake cleaner and a wire brush. Pay particular attention to the guide pins, and guide pin bores and make sure you don’t damage the rubber components.
Under no circumstances must any attempt be made to “re-work” the carrier, i.e. using a file to “clean out” corrosion. Any work of this nature can lead to excessive clearances to the pad abutments, which will result in clanking and rattling noises on braking. If necessary fit new guide pins and dust covers.