The timing chain functions just as that a timing belt does. The difference between your two is simply the material and area. One is constructed of metal and the other, a reinforced rubber. Though timing chains were used first, belts were introduced into automobiles in the 1960s. Belts are timing chain china quieter and because of their material, less costly to create. Timing chains are housed within the engine and receive lubrication from engine oil and can last a considerably long time, while timing belts can be found outside of the engine and tend to dry out and crack. In the last few years, however, more vehicle manufacturers have integrated timing chains back to some vehicles with vast improvements like a reduction in noise and vibrations, different then a timing belt not absolutely all water pumps are driven by the timing chain. Check your owner’s manual to know what kind of timing operation your vehicle utilizes as they may vary from year to yr and by a car manufacturer.