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The parts of an overhead-camshaft engine

The parts of an overhead-camshaft engine Camshaft The camshaft has pear-shaped lobes which actuate the valves - usually one inlet and one exhaust valve for each cylinder. Piston The piston is fitted with steel rings which fill the gap between it and the cylinder wall. Flywheel The flywheel is a heavy disc attached to the end of the crankshaft. It helps to transmit the engine power and to smooth out the individual impulses of the pistons so that the power flows evenly. Connecting rod The connecting rod converts the up-and-down movement of the pistons into rotary motion through a treadle action. Crankshaft The crankshaft transmits power to the road wheels through the gearbox. Sump The sump contains the lubricating oil for the engine's moving parts. A pipe from the oil pump draws up the oil through a strainer. Camshaft drive belt A toothed belt - often called the timing belt - drives the camshaft from a sprocket mounted on the end of the crankshaft. The camshaft rotates at half engine speed.