Did you know that your belts should be changed regularly between 60-90k miles. You will notice them starting to look cracked and worn out. Well, here’s a DIY to help you replace the old ones with new fresh ones!
BMW E-46 1998-2006
Make sure your engine is cold and off. After having your engine ready, inspect your drive belts for wear. The belts should be free from any cracks, fraying, glazing or missing chunks.
Working at top of radiator, remove the 4 expansion rivets from the intake air duct using a small fathead screwdriver to pry them up then pull the rivet out by the needle nose pliers. The expanding part of the rivet will then come out with the duct. Your car may have 3 or 4 expansion rivets, depending on the year model.
Remove the air duct from your radiator support by lifting it out of the intake air housing duct. Before you remove the drive belts make sure to mark the direction of rotation to be able to reuse them, and also take note of the installation position.
There are two different styles of tensioners, hydraulic and spring loaded. Each has a different way of releasing the tension.
If you have hydraulic style tensioners, remove the dust cap from the tensioner pulley. When it’s removed, you’ll have access to the 8mm Allen nut, which is used to rotate the tensioner.
If you have spring loaded tensioners, you should use a 16mm hex socket to rotate and release the tension.
Locate your A/C drive belt tensioner. Then use a 16 mm hex socketor to remove the dust cap to access the Allen bolt.
You can do this with a long handle and an 8mm socket or a 16mm open end wrench (depending on your car style), in order release tension and slide the belt off the pulleys.
Work your way slowly to install the drive belt exactly as you took it off. Make sure that the grooves are riding in the pulleys by following them with your finger. In case they’re not, the belt could break.
Then install the AC belt as well.
Finally, reinstall the radiator fan and you’re done!