Repair Review Car

1. Buy a timing chain that is made specifically for the BMW 525i 2.5L engine. Most auto parts store or online vendors carry the timing chain needed. Lift the hood of your vehicle and disconnect the negative battery cable. Remove the vibration damper and hub assembly to reach the upper and lower timing case covers. Remove case covers. Refer to the vehicle service or owners manual to identify vehicle parts.
2. Use a ratchet and pinch the upper timing chain tensioner to hold it in place. Use a wrench to remove the upper timing chain sprockets. Remove the camshafts that run along the side of the timing chain. Loosen bolts holding the upper timing chain guide in place. Remove the timing chain and upper timing chain guide. Remove the ratchet holding the upper timing chain tensioner. Remove the crankshaft sprocket and tensioning rail if necessary. Remove the Woodruff key.
3. Install the new timing chain. Replace the Woodruff key and reattach the crankshaft sprocket and tensioning rail. Reattach camshaft sprockets and tighten bolts using a wrench to 16 foot pounds (22Nm). Reattach and tighten lower timing cover bolts to 6.5 to 8.0 foot pounds (9 to 11Nm). Reattach the vibration damper hub bolt and tighten to 17 foot pounds (23 Nm).
4. Replace the upper and lower timing case covers. Start the engine to make sure the timing chain is installed properly.

1. Open the hood of the vehicle. Locate the sidelamp light assembly latch between the sidelamp assembly and the main headlight compartment. It is located halfway down from the top of the assembly. Depress the latch and lift the sidelamp light assembly out to the front of the vehicle.
2. Twist the bulb socket located on the back of the sidelamp light assembly in a counterclockwise direction and gently pull it out of the assembly.
3. Remove the side marker bulb by pushing it into the socket and turning it counterclockwise. Insert the new bulb by pushing it into the socket and twisting it clockwise.
4. Place the bulb socket back into the assembly. Reinstall the lamp assembly by sliding the guides located at the top and bottom of the assembly near the front headlamp into the tabs. Make sure it is secured and sealed before closing the hood.

1. Open your Mercedes hood so you can access the belt. Be sure the engine is cool before operating.
2. Loosen every bolt in the series that binds the belt into place. Take special care to remember the pattern in which the fan belt is attached. This is the same pattern youll follow to route the new fan belt. Do not remove the bolts, simply loosen them so that the belt looses tension at each point.
3. Pull the belt out of each connection, making sure you leave it intact so that you can compare it to the new belt.
4. Stretch the old and new belts out completely with both hands. Compare the size of each belt to make sure the new belt will fit your Mercedes engine.
5. Route the belt along each pulley, following the pattern you took note of when loosening the tension. Press down with a free hand after connecting the belt to each pulley so that you continuously create tension in the belt.
6. Tighten the belt at each point along the pattern by turning the bolts hard to the right, which will hold the belt in place.
7. Clean your workplace and put away all tools. Discard of the old fan belt.

1. Turn the engine of the M3 off and open the trunk. Put on a pair of clean gloves.
2. Use a Phillips head screwdriver to loosen the clip at the center of the trunk lid.
3. Fold the trim panel downward and pull the bulb socket down to disengage it form the electrical connector.
4. Rotate the bulb to the left and remove it from the bulb socket. Install a replacement bulb into the socket and rotate it to the right to secure it. Reattach the socket to the trunk lid. Once you hear a click, the bulb is secured.
5. Reattach the trim and the clip. Close the trunk lid.