The BMW Z3 is a two-seater sports convertible first introduced in 1997. The only engine available on the Z3 at that time was a 1.9 litre inline four cylinder engine. Like most modern engines, the Z3's power-plant uses a series of drive belts and pulleys to convert mechanical energy into an electrical current that's used to power components such as the car's air conditioning and cooling system. Replacing the main drive belt is an easy procedure that will require about 15 minutes of your time.
Park your Z3 on a level surface that provides enough clearance for you to get underneath the front bumper.
Locate the main drive belt pulley that sits at the centre of the engine at the front of the engine bay.
Insert the 8mm hex socket into the centre of the drive pulley and rotate it in a counter-clockwise direction to loosen the belt.
Keep the socket wrench twisted and slide the old belt out of place, replacing it with the new belt.
Release pressure on the socket wrench to tighten the belt system and then remove it from the centre of the pulley to complete the replacement.