==Introduction== The internal combustion (IC) engine has been used for many decades in developing countries playing a very important role in providing power for rural communities. Many stand-alone units are used for milling, small-scale electricity production, water pumping, etc. They are readily available, off-the-shelf in most major towns and cities in a range of sizes to suit various applications. There is usually a well-established spare parts and maintenance network, both at urban and rural centres.
There are two main types of IC engine defined by the type of fuel used; petrol (gasoline) or diesel. The petrol engine is widely used for small vehicles and light applications whereas diesel engines are more suited to continuous running for lengthy periods at higher load ratings and are therefore used more widely for stationary applications and commercial vehicles.