In many vehicle models, torsional vibration dampers (TVDs) ensure that the multi V-belt runs smoothly. However, they can start to display signs of wear and defects over time, so regular inspection is important. Continental has provided some useful advice on how to carry out effective checks. 

A multi V-belt transmits power from the engine to ancillary units such as the alternator, power steering hydraulic pump, air conditioning compressor, fan and the water pump. This means the belt  ensures the correct functioning of the engine and a high level of driving comfort. TVDs are used in many vehicles to ensure that the belts run as smoothly and with as little vibration as possible. They replace the rigid pulleys on which the multi V-belt normally rests and absorb vibrations through special elastomer elements. The engine runs more smoothly and quietly, with reduced slippage and  longer component life. Decoupled torsional vibration dampers go one step further, completely decoupling the belt drive from the crankshaft, preventing the transmission of torsional vibrations from the crankshaft.

Continuous stress and environmental influences in the engine compartment cause TVD elastomer elements to harden, resulting in chipping and cracking over time. In the worst-case scenario the outer part can even become detached from the inner ring. The sure signs of a defective TVD are fluttering multi V-belts, an unsteady tensioner and increased engine noise and vibration. These all lead to faster wear of the drive components, and in extreme cases even to breakage of the crankshaft.

Continental also point out that vehicles such as cabs, which are frequently operated at idle speed, and engines modified by chip tuning place particularly high stress on TVDs so need extra checks. 

Continental recommends checking the condition of TVDs on all vehicles after 60,000. In particular the technician should chect if the crack is visible or is the TVD deformed. Also Is there any spalling or peeling visible. 

On some torsional vibration dampers, indicators on elongated holes indicate the current state of wear. However, the TVDs should always be replaced after 120,000 km at the latest. This will avoid major damage to the crankshaft. It is good to know that although TVDs can be changed, they can’t be retrofitted because they’re always specifically matched to each engine.

With Continental replacement TVDs you no longer have to separately order the matching screws for the TVD washer. Its TVD washer range now has 10 new types, and each washer is supplied with a matching fixing screw. This is because the manufacturer’s specifications often stipulate that the right screw must also be replaced along with the TVD. These special expansion screws are now included in the Continental package covering the most important applications in the market:

• VD1094S e.g. for Citroen 1.6 HDi
• VD1080S e.g. for Peugeot 2.0 HDi
• VD1104S e.g. for Nissan 1.9 dCi
• VD1002S e.g. for VW 2.TDi
• VD1105S e.g. for BMW 3.0d
• VD1110S e.g. for Ford 2.0D
• VD1120S e.g. for BMW 2.0d
• VD1113S e.g. for Renault 1.5 dCi
• VD1127S e.g. for BMW 18d
• VD1031S e.g. for Opel 2.2DTI

These are available from Continental stockists.