July/August 2021

Integration Moving over to thermostats, Steve said: “Effective thermal control in all areas of the engine is vital in order to maintain the VM-claimed emissions figures, and although easily overlooked, it is the humble thermostat that ensures that this is correctly managed. Although generally reliable, AASA 2020 report data show that over a five-year period from 2014, the average thermostat failure rate has steadily increased to almost 5%. At the same time, the percentage of vehicles fitted with integrated thermostat housings and MAP thermostats, rather than a traditional thermostat design, has grown from 55% to 80%. “For example, the 1.4 and 1.6-litre petrol and 1.6-litre diesel engines used in the R56/57 second generation Mini feature a thermostat housing that is prone to be the source of leaks in the coolant system. These problems are generally caused by either excessive heat from the exhaust manifold or oil contamination. It also not uncommon for the thermostat valve to stick, which can result in overheating. Integrated housings like this are complex products and this directly affects their predicted service life and crucially, their cost, which is why they should not be considered an ‘anything will do’ product as the quality will directly affect both their ability to operate within the VM’s strict performance parameters and their expected service life, so OE quality must be the benchmark.” Smart cooling New methods for cooling have been developed in recent years. A vehicle’s thermal management system plays a key role in ensuring emissions efficiencies. According to Fatiha Laauich. Pan European Strategic Marketing Manager at DENSO Europe, this is why DENSO is pioneering Smart cooling: “A conventional cooling system places the radiator for the engine coolant, the transmission oil cooler and the air conditioning condenser and intercooler in front of the engine, which means that all these subsystems have to be cooled by the same airflow, creating drag and subsequently a lower cooling performance. However, they share the same cooling fan as the engine circuit, so even if only one system needs to be cooled, the fan will be activated, producing a high electrical demand. “In addition, the design constraints enforced by having all of the elements in front of the radiator means that the vehicle’s aerodynamics cannot be optimised, and in the event of a front-end collision, these vulnerable parts are exposed to impact and subsequent damage. “When it comes to heat dissipation in a Smart cooling system however, things are somewhat different. Although there are now two radiators situated in front of the engine, the transmission oil cooler, A/C condenser and intercooler can be located elsewhere, so optimising space and gaining aerodynamic advantages. The high temperature cooling loop is only for the engine, whereas the low temperature loop and radiator allows the vehicle’s subsystems to be cooled independently, and acts as a cold buffer reducing the need for forced ventilation from the cooling fan, which reduces power demands.” Fatiha added: “It also reduces the amount of fluid that needs to be cooled, which maximises the performance of the engine and reduces emissions, and simplifies the integration of additional subsystems, such as batteries and e-motors, as these can be cooled by the low temperature loop.” JULY/AUGUST 2021 AFTERMARKET 39 EYEBROW www.aftermarketonline.net With the weather warming up, there is a distinct possibility that there will be an increase in cooling system related problems ” / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / '2 +(-') (+1, -*102 +,+(-') -.-0 - (+'--, ' Y AWA ) -1.-01 --+1 1 01 01 - -- (-' 210 .1 -.( - 01-,0-01 1-'((0- -*-. * 01+( * 2 * * 0- ,+ 1 )('' &%&& $%# #$"$ ,' ,+ 1! (',.- 1 '.' 0, (+ 1