The stop-start of something big

Traffic jams: the scourge of modern motoring. No journey and no road is immune. All that time spent stationary, wasting time, wasting money, wasting fuel. Or at least that was the case until a few years ago, before the engine stop-start system became a common fixture on modern vehicles – and now the tiresome traffic jam is a situation in which drivers can actually save both fuel and money. 

That’s because modern engine stop-start systems are so intelligent that they are able to unobtrusively shut down the engine as soon as the right scenario is reached, and, equally unobtrusively, instantly restart the engine when required. 

On the surface, the stop-start system is a simple thing – after all, it merely switches off the engine and restarts it at the appropriate moment, but that’s to do it a disservice. It has made a vast contribution to the lessening of vehicle fuel consumption and emissions, and the engineering behind it is far more complex than you might suspect, not only in terms of making components last, but also its utilisation of lubricants and fuel systems cleaners that can keep the engine running at its optimal level. 

The technology

Many dismiss the engine stop-start system as simply a more rugged starter motor and a stronger battery, but they’re entirely incorrect to do so. The system is activated when a car comes to a halt and either the manual gearbox is placed in neutral or the driver of an automatic car keeps the brake pedal depressed. So it requires a range of sensors to detect everything. It also needs to work instantly, every single time. 

Every single time means a vast number of times, because before the advent of stop-start technology, the ignition and starting system would be expected to perform between 40,000 and 60,000 start-ups during a car’s lifetime. However, modern stop-starts systems have to cope with around a ten-fold rise in the number of start-up procedures they’re required to perform. 

The number of start-ups is even greater in cars that contain hybrid technology in which the conventional engine is paired with an electrical motor. This is because the car can switch off the engine while it’s in motion and run on electrical power alone, but this also means the engine must also be restarted while the car is in motion, not just while it’s sitting still. 

The strain on the mechanical componentry is huge, but the burden placed on an engine’s fluids is even greater, because not only must an engine be lubricated during a cold start, it must also be during repeated hot-start procedures. 

For example, a crankshaft bearing contains no ball bearings as such; the flat surface of the bearing is kept separate from the flat surface of the engine housing simply by a layer of oil which is pressurised as the engine runs. When the engine stops, the oil stops flowing and the surfaces rest together, the only protection the surfaces have is the miniscule layer of oil that remains between them. High quality engine oils have special additives and technology as part of their chemical make-up to help combat wear in this situation, until the re-pressurised oil can begin to lubricate the bearings and engine again. The delay between turning the key and fully lubricating the engine may be a matter of seconds but, without protective technology, premature engine wear would be instant. 

This is where the research employed by brands such as Texaco Havoline really pays off, because the latest Texaco Havoline ProDS oils, are designed to protect modern engines during repeated start-up cycles and during normal running. Advances including Deposit Shield Technology keep the insides of the engine cleaner than conventional oils, coating vital engine components to reduce premature wear, while helping prevent the build-up of unburnt start-up deposits that could both impair the engine’s efficiency and cause damage. 

In addition, the fuel system is also subjected to this vastly increased number of restarts, and so the use of system cleaners such as Techron is vital to help ensure that deposits from fuel contamination never build up to levels which start to impact on engine and fuel injector performance. A good fuel system cleaner is formulated to mean the fuel/air mixture is always right and the car starts immediately, every time. 

Coolant also plays a vital role in helping ensure that a car runs as efficiently as possible. A coolant must allow a car’s engine to reach optimal operating temperature as quickly as possible, and keep it there regardless of the external temperature and whether or not the engine is running as the car moves or is being subjected to numerous hot starts while stationary. Again, products such as Havoline Xtended Life Coolant provide an essential service, because in addition to their role as a coolant, they also reduce the development of corrosion in the car’s cooling system. 

The future

Engines are getting smaller and are being turbocharged and supercharged to keep their performance up while reducing their emissions and fuel consumption. Hybrid systems will become more prevalent, and self-driving cars will be expected to take people where they want to go with the minimum of intrusion.