Cables
CablesControl cables are used in a wide range of automotive applications from safety critical parts to accessories. The function of all automotive cables is simple: linking two points to actuate an operation at one end of the cable by performing a function at the other end.
All brake, clutch and accelerator cables are safety critical parts. Replacement cables undergo the same rigorous quality assurance measures and testing phases as the OE product. Co-operation between OE and aftermarket manufacturers ensures that the highest standards are maintained across the automotive industry. The production of all types of metal outer-casing, and the extrusion process to which it is subject, require specialised machinery to guarantee a consistently high quality of finished product. Computer aided design (CAD) systems and failure modes and effects analysis (FMEA) techniques are used to monitor the product throughout development. The extrusion of inner tubes – the component that ensures smooth performance and durability – also utilises high-tech machinery. The production line is often controlled by a three dimensional ultrasound system to guarantee consistent production quality, thickness and dimensions. Cables are generally located in hostile environments such as the vehicle underside, so they must be able to withstand extreme temperatures and chemical exposure. Several environmental and performance related tests are carried out in line with the current OE requirements, such as proof load testing during cable assembly and on finished cables. Inner cable load testing can be up to 250 kilograms, whereas the average pedal effort needed to clear the clutch is 17 kilograms. Other tests include: • Salt Spray Resistance • Temperature • Performance • Cyclic Fatigue Replacement Issues If a brake cable is not functioning correctly it may mean that the brakes will not hold the vehicle in a parked position. If a clutch cable is beginning to fail then the driver may not be able to engage gears smoothly, if at all. Should an accelerator cable lose functionality, the pedal progression may not be smooth. If a speedometer cable becomes worn, then the instrument on the dashboard may cease to record vehicle speed accurately. First Line recommends that the following points are observed during cable replacement: 1 Identify cause of initial failure – have any associated parts seized? 2 Check route of existing cable to ensure correct routing on replacement. 3 Check for obstacles or intrusions that impede operation of the cable. 4 Use appropriate tools – use of pliers or vice grips on the inner cable will compromise performance and accelerate deterioration. 5 Check that the cable does not interfere with operation of the suspension, steering, exhaust system or other ancillary components. 6 Replace brake cables in matching pairs to ensure braking is evenly balanced. Premature failure of a clutch cable should always be thoroughly investigated as proof testing far outweighs the average pedal effort applied to the clutch pedal. The cause could be a faulty clutch release mechanism or the clutch itself may need replacing. Alternatively, premature failure can be due to “work hardening” of the inner clutch cable which can, in turn, be caused by incorrect installation/ misalignment or kinking in the inner cable, for example by using pliers to install. Common failures are normally due to general wear and tear, but it is always worthwhile conveying the importance of correct fitment to the installer at every opportunity. This can be best met by fitting the correct part in the first place. First Line cables not only provide the range, but can also ensure that the installer has all the catalogue and technical information necessary to do the job right first time. |
Safety First