Alternator April 27, 2020, 06:29:15 PM Thanks to eddypeckThe alternator is a dynamo that generates an alternating current.The role of the alternator is to charge up the battery while the engine is running. Car batteries deliver power to your headlights, stereo and a number of other electrical parts inside your car and it needs to be recharged.Alternators are used as a battery charger, delivering new energy to the battery so that it has all it needs to deliver power to the car time and time again. Many believe that the car not starting is down to a fault with the car battery, when in actual fact it is the alternator to blame for not recharging the battery, allowing it to go flat. The alternator is driven by a V belt off the main crank pulley. The belt also runs the water pump so should the belt snap you might think it's OK you could run without electrics, but this is not the case as you'll very quickly overheat.The arrangement of the belts will be something like this. Depending on the configuration with or without Power Steering or Air con it may be slightly different.1 - Pulley - Alternator 2 - V belt - Alternator, coolant pump and crankshaft 3 - Pulley - coolant pump 4 - V-belt - crankshaft and P.A.S. vane pump5 - Pulley - P.A.S. vane pump 6 - Pulley - crankshaft Tensioning the belt is done moving the alternator rotation, there is often a toothed bracket and cogged bolt system to help. Last Edit: April 27, 2020, 07:39:35 PM by vw-widow