Now we've already discussed the starter motor and see the electrical connections on the side here. But in order that we don't have a flat battery, sometimes called a dead battery, we're going to need an alternator. Now I'm not sure if we've got one on this engine, but I'll have a look around the other side. Because can see that there are some devices that are run directly off the engine crank shaft, we're using a belt on this arrangement, a B, a belt, maybe gears, maybe a chain. So let's have a look at some of the things that are running off the engine. We've got this round circular one here.

This may be perhaps a jacket water pump. We've got a tensioning device that keeps the belt tight. We've got another device here. I believe that's for lubrication or system. And again, we've got a tensioner to keep the tension on the belt. Always the same.

We don't want to slack belt we always want it to be quite tight. Now I can't actually see See the alternator on this particular engine, which is quite interesting because it should definitely be there. But irrespective, normally you will have an alternator that is driven off the engine itself. And this is what we call a parasitic load. In fact all of these loads here you can see one load here, another load up here. Those are parasitic loads, they're drawing energy away from the crankshaft.

So we're not using that energy to make the car move or anything like that. We're just using that energy to supply our life support systems such as the jacket, water pump, lubrication or pump, maybe the alternator, etc. The alternator charges the battery, so we'll use a lot of current to get the engine started. And then we're going to replace the current by using an alternator which is going to feed electrons to the battery which is going to restore The battery back to its normal working condition. Think of a battery a little bit like a tank for electrons. If you take the electrons out of the tank or out of the battery, you need to replace them.

Again, there's not an infinite amount of electrons in a battery. So if we draw 50% of the electrons out of the battery, just to get the engine rotating, then we need the alternator to feed electrons back into the battery so that the battery is full of electrons. Again, if you have a flat battery, it means that all of the electrons have left the battery they've flowed to a different area. So we've got the alternator, which is filling battery up with electrons. And then we've got the starter motor, which is using a lot of those electrons to start the engine. But there are other things that are going to draw electrons out of the battery or directly from the alternator itself.

If you've got loads of flashing blinking lights, When you drive your car, such as when you light up the interior of your car, even switching on the small lights and the front of the back, or when you turn your headlights on, or even when you have those red hazard lights on, they're all drawing electrons from the battery or if the engine is in service, sometimes several the electrons directly from the alternator. So the electrical system not only consists of the battery and the alternator, which are essential in order to start most engines, but the electrical system may also be used for many other auxiliary keys, such as for headlights for hazard lights, for electronic displays, etc. Another area though, where you're likely to see a lot of electronics is the electronic control system associated with the timing of the engine. You may use a complete electronic system for the fuel injectors via zoom in we may see that these fuel injectors are electronic and may be BC the fuel connection coming down here.

See the fuel injectors. These fuel injectors do not appear to be electronic. Some fuel injectors are having electronic fuel injectors just increases the engines overall efficiency because we can more specifically time when the injector opens and closes. A lot of modern medium and large sized engines. In fact, even quite small sized engines used in cars are going to be completely controlled electronically. All of the temperature alarms, pressure alarms, temperature sensors, pressure sensors, level sensors, all of that information is going to feed into a central computer.

We call this an engine control unit, sometimes engine control module, or sometimes even electronic Gov. But the point is all of that information floods into this Computer and we're going to use that computer to control the engine. You can think of it as being the brain of the engine. And because it's the brain of the engine, it is very, very important. It might be a relatively small component on the engine. But if you have any problem with this engine control module, the whole engine will no longer function.

Now, I've personally experienced this when I was on a ship floating around just off the coast of France. And both of our engines died at the same time. And we couldn't get the engines restarted, and we were drifting closer and closer to the coast. By the time we actually got the engine started again, we're about 200 meters away from land, which is where you don't really want to be when you're on a ship. The problem we had was that somebody had taken the engine control module and mounted it onto the side of the engine. When the engine became hot was actually mounted roundabout here.

The engine control module overheated, and it became very erratic. injectors were injected at the wrong time, the engine was accelerating and decelerating very rapidly and eventually the engine just shut down. Now, it took us quite a long time to find the cause of this issue. And it was actually by taking the engine control module off the engine that allowed it's cooled down. And then we discovered this was actually the problem. Now I'm a big fan of increasing engine efficiency.

And I definitely believe it's a really good thing if you can get more power out compared to what you put in. But the reliance upon electrical systems nowadays, especially electronic control systems, has gotten to such a point that if you do have any problem with a electronic governor, the engine will no longer operate. So keep a lookout for that. If you have a modern engine you're experiencing slightly erratic problems. The battery can explain very easily.