Aftermarket July/August 2022 Issue

W ith MOT and servicing patterns disrupted by the pandemic, some vehicles may have braking system issues. Commenting on the main causes of brake noise, Comline’s brake doctor, Dr. Keith Ellis, said: “Arguably, the most common form of noise is brake squeal; in simple terms, squeal is caused by vibrations that result from the interaction between a brake disc, brake caliper, and brake pad. Squeal is directly influenced by various internal and external factors, including the temperature of the disc or pad, the ambient temperature in which they are operating, the speed that the vehicle is travelling, and the pressure being exerted under braking. “Brake pad shape can also influence brake noise, particularly under light braking pressures. The wrong shape can result in excessive noise, which is why you will see such a variation in pad shape by make and model and the use of noise prevention technologies, such as backing shims, slots and chamfers.” Known source On how to detect the cause of brake noise, Dr. Ellis said: “Ask the vehicle owner to explain the noise and when it occurs or, alternatively, conduct an initial test-drive to help establish a prognosis. Technical Service Bulletins may also advise if the noise has a known source and are a handy point of reference. Inspect the brake system and associated components; brake noise can be magnified or even caused by faulty components outside of the braking system.” On how to prevent excessive brake noise, he added: “Check the brake disc for wear and corrosion; Replace disc or remove corrosion as required. Clean the inside and outside of the caliper using brake cleaner to remove any dirt and corrosion. Clean the caliper slide bolts and end pad where it sits on carrier, then lubricate with specialised braking grease. Extra care should be taken to avoid greasing the face of the pad. Replace any damaged brake hardware, ensure brake pistons are fully retracted into the caliper and ensure the correct fitment of shims and accessories.“ Dr. Ellis added: “Educate the vehicle owner about the importance of ‘bedding-in’ new pads and discs for the first 200 miles.” For more information, visit: www.comline.uk.com Brake fluid check According to Colin Cottrell, Marketing Director at LKQ Euro Car Parts, it’s also worth checking when customers last had a brake fluid change: “Brake fluid is hydroscopic, meaning it takes on water over time and therefore needs regular checks and changes to keep it functioning at its best. It is designed to work to a set boiling point, and needs to withstand temperatures of up to 260°C. So, if it becomes 40 AFTERMARKET JULY/AUGUST 2022 BRAKES www.aftermarketonline.net BRAKE IT DOWN Safety-critical systems like brakes may have been overlooked in recent years, so you need to make sure you are looking after your customers diluted with water, this boiling point begins to drop. In time, this can cause vapour lock in the braking system, meaning brakes can fail completely when customers hit the pedal. when a check is required, it only take a few moments to carry out. Kit such as the Pagid Brake Fluid Boiling Point Tester allows you to take a sample of fluid and generate a reading instantly. For more information, visit: https://omnipart.eurocarparts.com or lkqacademy.co.uk Vital procedures Support is available. Jon Roughley, Global Marketing Director of First Line, said: "When it comes to installing brake pads and discs, it is essential that vital procedures are not overlooked, as this may lead to premature failure of the new components. Calipers, for example, need to be able to operate freely, so must be clear of dust, dirt and corrosion and caliper bolts, where applicable, should be replaced, as many are single use only and must not be reused. “If there are slider pins, these need to be cleaned and lubricated with a suitable silicone-based lubricant and, if they have been on the vehicle for a long period of time, any clips should be replaced, as their tension will have been severely reduced. Wear leads that are not an integral part of the pad should also be replaced when required for the application.” For more information, visit: www.firstlineltd.com MINTEX: Brake disc replacement ON the steps needed to change a brake disc, Scott Irwin, Head of Technical Training at TMD Friction’s aftermarket said: “Before starting the brake repair process, look for signs of uneven wear on the brake discs, as well as checking all components surrounding the axle and examining the Above: Following brake disc installation procedure helps prevent brake judder later on