FOR THE NOVICE

NZ Truth, Issue 1030, 22 August 1925, Page 16

FOR THE NOVICE

v;: — — ■ ■ The power unit of a car consits of the following main components: — THE ENGINE PROPER, comprising the cylinder block, the pistons, the crankshaft connected to the ' pistons by the connecting rods, the camshaft operating the valves and driven by the timing wheels, the flywheel fitted on to the crankshaft, and the drive for the ignition system. THE IGNITION SYSTEM, comprising the magneto (or coil and distributor) and the sparking plugs, and THE CARBURETTER. These parts are essential to all engines, and for this reason it will be found useful to distinguish them from the following parts, which are usually associated \Vith the power unit but which are refinements and not actually essential to the operation of the engine:— THE RADIATOR is almost universally used on cars m connection Avith the cooling system. It can be dispensed with by the use, of air-cooling arrangements, but its use is so general that manufacturers who fit air-cooled engines usually fit dummy radiators m order to make their cars look orthodox. THE DYNAMO.— It is oC some importance to realise that this machine is not actually a part of the engine at all, but is an entirely separate machine

driven by the car. Its function is to provide current to charge the battery, from which it may be drawn at any time to operate the various electrical accessories about the vehicle. Among these is the STARTER MOTOR, which is also a separate electrical machine, capable of driving the engine for short periods using- current drawn from the storage battery. In the succeeding articles each o* these components will be dealt with m detail.