Dayco, has introduced several new references into its aftermarket programme which demonstrate how it is driving technological change as an OE supplier.

One of the key introductions is the auxiliary belt tensioner and water pump friction wheel drive for the PRINCE BMW PSA engine utilised in many common vehicle models such as Mini Cooper S, BMW 1-3 series, Citroen C3-C4, PSA 208-3008. In this engine the system that controls the water pump is activated only when the temperature of the engine needs to be controlled. Dayco designed, developed and manufactures for OE fitment, both the unique single-arm torsion bar tensioner, which replaces the traditional spiral spring tensioner on the auxiliary drive system and the motorised ‘switchable’ friction pulley that actuates the water pump.

At start-up, or whenever the engine is operating below its optimal temperature, the water pump is disengaged, which decreases the engine’s warm up time, reduces its overall emissions and improves fuel consumption. However, once the engine reaches a predetermined temperature, the friction wheel is activated, and the water pump engaged, therefore allowing the engine to optimise its thermal management. To prevent excessive acceleration forces on the bearing during off-on operations, the friction wheel is in constant contact with the crankshaft pulley, but with the use of an electric motor and small planetary reducer, which works in conjunction with a multi-function control system, the pulley’s radial movement is altered, and the rotating friction wheel comes into contact with the surface of the water pump pulley and thus the water pump is brought into operation.

Due to the confined space around these components, a traditional auxiliary belt tensioner could not be employed, which therefore required Dayco to design another innovative solution, this time in the form of the single-arm torsion bar tensioner for the auxiliary drive system.

Both the friction wheel, belt and tensioner, along with the water pump and its pulley, are all now part of Dayco’s aftermarket programme, which allows independent workshops to offer their customers a like-for-like replacement that provides them with an alternative to the franchised dealer. Dayco also offers the replacement auxiliary belt, plus a wide range of parts and kits for this popular engine.