October 2020

Right: Dayco timing kit with water pump T iming systems have evolved as even greater demands are placed on the internal combustion engine, and the engines themselves become more complex. Dayco UK’s National Sales Manager Steve Carolan observed: “Although fundamental changes, like the introduction of the timing belt as an alternative to a chain, are rare, new solutions such as the belt being enclosed inside the engine, exposed to, and immersed in, its oil, are still pioneered by Dayco. “Drive system tensioners have also developed over the years from relatively simple devices, to complex designs, engineered to overcome specific issues and Dayco’s ‘green’ tensioner for the VW’s EA288 family of 1.2, 1.6 and 2.0-litre diesel engines, is an excellent example of an inventive solution for reducing the force normally required on the auxiliary drive belt. “Naturally, a force needs to be allied to the belt to maintain its tension and prevent it from slipping, but also to keep it running smoothly and avoid any backlash as the engine transfers between being under load when accelerating and over running when braking, for example. The greater the tension, the more power is sapped from the engine, so conversely, a reduction in the tension required provides direct efficiency gains. “By working closely with VW’s design engineers, the Dayco team developed a new accessory drive geometry and tensioner design that reduced the nominal tensioning force by 35%, which has resulted in a direct reduction of 0.5 g/km CO2 emissions for these engines.” Developments Other developments include changes such as the relatively recent move by some VMs to integrate the water pump into the timing system, instead of it being driven by the auxiliary belt. “This has a direct effect on the aftermarket,” observed Steve, “because, in contrast to the auxiliary belt, which rarely has a scheduled replacement interval, the timing belt does and this means that technicians now come into contact with the water pump more frequently than previously, making it far easier for them to assess its condition. As a consequence, more are found to be either in need of replacement, or are being changed as a sensible precaution, so sales are on the rise. “Dayco has proactively responded to this development by offering water pump kits, which include all the necessary replacement drive components, as well as the water pump, to provide workshops with a complete aftermarket solution. “Sometimes, for the best of intentions, workshops will try to save their customers money and replace only the belt and its ancillary components. However, this policy runs the risk of their customers having to face a much larger bill to virtually replicate the job, if the water pump fails at a later date. “It’s sensible to change both the water pump and timing belt at the same time, as it is a far more cost- effective solution for motorists in the long run and also gives them confidence that their vehicle has benefitted from a full and thorough system overhaul. Steve added: “OE-derived 34 AFTERMARKET OCTOBER 2020 TIMING SYSTEMS www.aftermarketonline.net Timing is everything, as the saying goes, but with timing systems, the key is increasingly about the approach TIMING AFTER TIME