MOTORING
Modern technology has made engines lighter and more efficient in comparison to older ones that were made of cast iron. Most modern engines are made of aluminium alloy.
This makes the process of manufacturing it simpler and faster.
Besides, recycling it is far much easier since aluminium melts at about 4370C. Aluminium is a good heat conductor and dissipates heat faster.
However, aluminium is sensitive if the temperature regulation is not done well.
If the cylinder head and block buckles or cracks, in most cases, the bolts that tighten the cylinder head on the block lose grip.
In engines, where the block is made of cast iron, it is only the cylinder head that gets affected.
Resurfacing the head and re-installing it with another head gasket, can solve the heating problem.
For modern engines, such as that of the new model Toyota Harrier, Wish, Noah or Voxy, once the engine block is affected by heat, even the cylinder head bolts will be pushed out and the head will not be tightened.
In such cases, most people end up buying a new engine, but mechanics have found out a way of going around this.
All they do is to get a fitter machinist who will re-thread the cylinder block. Then, the mechanic will use oversized bolts that line up with the threads that have been cut by the fitter machinist.
Once this is done, the head is then resurfaced and re installed on the engine and the engine should work well.
Another technique which is employed, involves rewiring the cooling fans that are supposed to be triggered by the thermostat switch to the ignition circuit, such that immediately the ignition is turned on, the fans will begin blowing the radiator.
This will prevent the engine from reaching high temperatures because cooling of the fluid will happen at the start of the engine. With this technique, it will be hard for the engine to overheat again, especially if there are no leakages of coolant and the engine has a good pressure cap.