V-SMART June 2018

Welcome to our Technical Service Bulletin page! Here you can find a snapshot of our latest Technical Bulletins produced by the Valeo Technical Team. All Technical Service Bulletins can now be found on our new Technical Library page at: www.valeoservice.co.uk

Keeping you up to date with all out latest technical literature

the torsional vibrations inside the crankshaft.

In fact the vibrations/pulsing felt through the clutch pedal are a result of axial torque deviations in the crankshaft conveyed right through to the clutch pedal via the clutch hydraulic line. To suppress these vibrations some engines are fitted with a frequency modulator that is situated within the hydraulic clutch actuation system. The frequency modulator absorbs these disruptive vibrations that occur within the clutch line and prevents vibrations/pulsations more specifically when using the clutch pedal. The oscillation absorber works in the static range as opposed to the frequency modulator which works in the dynamic range. Different dampening levels appropriated to the oscillation absorber are defined by the vehicle and engine set up. These oscillation absorbers are made from plastic and are situated in many clutch hydraulic lines the part is subject to wear and faults over a vehicle lifetime. This should be tested when the vehicle is stationary to check for vibration that may be felt through the clutch line. Crankshaft pulley/torsional vibration damper Part Number: 836161, 836162, 826740, 826550, 835071, 828392 For Vehicle: Peugeot, Citroen 1.6 HDI Engines The Valeo Service Technical department have received several claims stating that after fitment of the components listed above, vibration and or judder can be felt through the transmission. After investigating the issue Valeo technicians have identified that the clutch/flywheel kits are not at fault and the defect can be due to a worn, damaged or faulty crankshaft pulley/Torsional Vibration Damper. The crankshaft pulley/TVD directly reduces

It is recommended that the crankshaft pulley on these vehicles are changed during every flywheel replacement as the components are susceptible to wear, deformation and cracks in the rubber damping element of the TVD. In other circumstances it is also possible that the bushes on these units have become damaged and/or total failure of the unit resulting in strong vibrations or an immediate breakdown of the vehicle. Crankshaft pulley technology can differ dependent on application so it is always best to check with the dealer to ensure replacement is performed correctly

Visit our technical library today for more useful technical literature for you and your customers

17