How Do Gears Work in an Engine?

Gears inside an engine dont directly drive the wheels. Instead, they act as a “precision conductor,” with their core function being to ensure strict synchronization between the valve train and the crankshaft.

When the engine is running, the crankshaft drives the camshaft gear to rotate via the timing belt or chain. The meshing transmission of this pair or multiple pairs of gears ensures that the camshaft and crankshaft speeds maintain a fixed ratio (usually 1:2).

The gears on the camshaft, through their specific contours, precisely control the opening and closing timing (valve timing) and lift of the valves.

This synchronization is crucial: the intake and exhaust valves must open or close at the precise moment when the piston is at top dead center or bottom dead center to ensure the engines normal intake and exhaust.

Any slight desynchronization can lead to reduced engine power, shaking, or even serious damage. Therefore, the gears in the engine are the core timing device that ensures its efficient and smooth operation.