Date: Wed, 04 Jun 1997 11:14:59 -0700
From: Terry Lee <tlee_at_atwc.teradyne.com> Subject: How to change E36 M50 belts

E36 M50 ACCESSORY BELT AND AIR CONDITIONER BELT REPLACEMENT

The M50 uses a spring loaded idler pulley to maintain constant tension in the accessory and air conditioning belt. The idler pulleys are hinged on a pivot and the tension is applied to the pulley arm via a spring loaded device that looks like
a stubby shock absorber. Changing the belts simply requires pulling the idler pulley
back so that the belt is slack enough to remove and replace. I found the easiest way
to back off the idler pulley is to pop the cover's off of them, inserting a long arm
8mm hex wrench, and then turning the idler pulley on it's pivot against the spring.

The dealer's will charge you $125. Independent parts suppliers will provide you both
belts for under $50. It takes under 30 min for a do-it-yourselfer.

Tools:

        Philips screwdriver - #2
        Slotted screwdriver (about 3" long)
        8mm long arm hex wrench
        trouble light or flashlight

1. Open the hood and remove the cover/air duct over the radiator fan, which routes

   cool air to your alternator. There are 4 screws plus two push-in expansion fasteners.

2. Jack up the front of the car, supporting it on jackstands.
3. Remove your lower baffle, this is the rectangular piece blocking your view of

   the belts from below.

4. Using the small slotted screwdriver, pry off the plastic center cap on the idler

   pulley of the air conditioner.

5. Insert the 8mm long arm hex wrench into the bolt holding the idler pulley on.
6. Push up on the wrench, to remove tension on the belt. Remove the air conditioner belt

   while it's loose.

7. Make a sketch of the serpentine routing of the accessory belt - once it's off, it's

   not obvious how the routing goes.

8. Pry off the plastic center cap on the idler pulley of the accessory belt, and insert

   the 8mm long arm hex wrench.

9. Push up and towards the center of the engine on the wrench, to remove tension on the

   belt. Remove the accessory belt while it's loose.

10. From the top, snake the accessory belt carefully around the radiator fan, taking care not

    to put dents into your radiator fins.

11. Reverse the contortions, to get your new accessory belt into the correct serpentine

    position.

12. Back off the idler pulley and then slip the accessory belt into place over the idler pulley.
13. Pop the accessory belt idler pulley cover back on.
14. Place the new air conditioner belt into position.
15. Back off the idler pulley and then slip the air conditioner belt into place over the idler pulley.
16. Pop the air conditioner idler pulley cover back on.
17. Re-install your lower baffle and cover/air ducts.