Repair Review Car

1. Remove the front grill, which is held on with two screws at the top. Remove the outside temperature sensor by squeezing the prongs and pulling.
2. Unbolt the front support located behind the grill. There are four 10-mm bolts, three 8-mm bolts and two screws at the bottom. Remove the clips from the hood-release cable and push them to the front of the car.
3. Remove the secondary radiator. Its held on with two 10-mm bolts at the bottom. Remove the two hoses, and let the coolant drain into a pan.
4. Loosen the 13-mm bolt that holds the alternator to the block. Use a 13-mm wrench on the alternator bracket, turning clockwise to loosen the belt.
5. Remove the compressor belt for the A/C with a 14-mm wrench on the bottom and a 15-mm wrench on the top. Remove the power steering pump belt with a 15-mm wrench and a 13-mm wrench behind the pulley.
6. Remove the bracket shaped like an upside down L from the passenger side of the block with a 17-mm wrench.
7. Remove the plastic cover for the belts that is attached to the block and held on with 6-mm Allen bolts.
8. Remove the crank pulley. First remove the four 6-mm Allen bolts from the pulley and then the center bolt with a 27-mm socket. Put the car in fifth gear to keep the motor from turning.
9. Remove the metal cover located in front of the timing belt, held on with two 5-mm Allen bolts.
10. Put the crank bolt back in and with the car in neutral, turn the motor with a socket on the end of the crankshaft bolt until the small dot on the crankshaft pulley lines up with the arrow on the valve cover. Mark the dot and arrow with a marker or paint.
11. To make sure the motor is at top dead center (TDC), remove the first spark plug and use a long screwdriver to make sure the piston is at the top of its travel.
12. Remove the camshaft gear with the timing belt still on and car in fifth gear to keep the motor from turning. Remove the camshaft gear and timing belt. Put car back in neutral after it is loosened.
13. There is an inner metal plate that needs to be removed with a 10-mm and 13-mm socket. There are three bolts on the front, one on the passenger side and on for the water pump.
14. Remove the remaining 6-mm Allen bolt for the water pump and remove the pump.
15. Put a new seal for the water pump and reinstall the water pump (or install a new one); install in the reverse of removal.
16. Reinstall the camshaft gear, aligning it with the timing marks. Make sure the crankshaft is also still aligned with the arrow on the valve cover.
17. Once everything is aligned, install the new timing belt and rotate the water pump to set the timing belt tension. You should be able to just twist the belt to 90-degrees with your fingers.
18. Reinstall everything in the reverse of removal. Bleed and top up coolant system.

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.