It is a cold dark morning, with snow starting to fall. Jumping into the van on the way to work, you start the engine which does so grudgingly after failing to catch the first few times. The heater finally starts to remove the freezing conditions in the van and the radio starts to cut out, soon after the lights on the dashboard start to dim. After a few minutes the heater and the radio cut out completely. As the cold returns to the vehicle the headlights start to flicker and get to the point of being highly dangerous, and finally the engine starts to miss, before, as with everything else in the van it stops working. This is just one example of a vehicle alternator taking its final breath.
The alternator is a very important part of a vehicle’s charging and electrical system. You can find it near the engine of the vehicle and is easy to spot as it is a belt-driven device. The alternator has a small pulley mechanism attached to it on the front side, the alternator belt rides on this pulley and is responsible for the working of the alternator. At the centre of the alternator is basically a big magnet surrounded by coils and wires. When the alternator belt spins the alternator, the magnet will rotate around the collection of coils and wire, which causes an electrical/magnetic field to develop. The alternator then uses this electrical/magnetic field to send power to all the vehicle components and will also recharge the battery. The alternator works together with the battery to supply power when the vehicle is running. The output of an alternator is a direct current, however AC voltage is actually what is created and this is then converted to a DC voltage as it leaves the alternator on its way to the battery. It is vital that the alternator gives a good performance because if it does not it will be unable to supply power to any demanding devices the vehicle may have. Because of this, many people have bought high power alternators.
If the engine of the vehicle begins stalling or cutting out, it is one of the best indications that the alternator is too weak to keep the vehicle going. If this happens, stop driving the vehicle to prevent additional damage to the vehicle. Continuing to drive the vehicle while this is happening, could cause it to overheat which can lead to a much more serious problem, such as a blown engine, if this happens while driving it could mean a call to your commercial vehicle insurance company.
A warning sign that the alternator of the vehicle may be starting to fail is often an unusual noise emanating from beneath the bonnet. A failing alternator will lead to failure of the bearings, and this could cause a spinning or a rattling noise coming from the alternator. If this sound is heard it is a very strong indication that the alternator is on its way out. If this noise is heard, get it looked at by a mechanic who will be able to say if the alternator is shot.