How to Replace a Belt on the 126 Mercedes


Replacing the Serpentine Belt
1. Open the hood and disconnect the negative terminal cable from the battery. Locate the belt routing diagram on the fan shroud. If the diagram is not present, consult the owner's manual for the proper belt routing procedure.
2. Use a ratchet and socket to rotate the tensioner counterclockwise. Once tension is removed from the belt, slide the belt off of the tensioner pulley. Slowly move the tensioner back to its original position.
3. Route the serpentine belt around each fan blade. Remove the serpentine belt from the engine.
4. Route the new serpentine belt around the fan blades and onto the pulley. Route the new belt around each pulley according to the belt routing diagram. Make sure the new belt lines up properly on all pulleys.
5. Rotate the tensioner and slide the belt underneath it. Slowly release the tensioner and allow it to add tension to the belt. Reconnect the negative terminal cable to the battery and close the hood.
Replacing the V-belts
6. Open the hood and disconnect the negative terminal cable from the battery. Locate the belt routing diagram on the fan shroud. If the diagram is not present, consult the owner's manual for the proper belt routing procedure.
7. Locate and loosen the bolts holding the accessory in place with a ratchet and socket. Move the accessory slightly to relieve tension on the belt. Pull the belt off the accessory pulley and remove it from the engine compartment.
8. Route the new belt onto the pulleys according to the belt routing diagram. Move the accessory back to its original position to reestablish tension on the belt. Tighten the bolts with the ratchet and socket. Reconnect the negative terminal cable to the battery and close the hood.