Genuine BMW Z3 Timing Cover

BMW Z3 Timing Cover Parts Questions & Answers

• Timing Case Cover, Bottom
  11-14-1-703-666
  Q: What are the removal and install Timing Chain and Timing Cover procedures for various engines?

  A: Disconnect the negative battery cable and drain the cooling system through the bottom of the Radiator. Remove the radiator and fan. Disconnect all electrical plugs, remove the attaching nuts, and remove the air cleaner and airflow sensor. Note and mark the wiring connections, then disconnect all alternator wiring. Unbolt the alternator, remove it and the drive belt. Unbolt the power steering pump, remove the belt, and move the pump aside, ensuring the hoses are not stressed. Remove the 3 bolts from the bottom of the bell housing and the 2 bolts below it which fasten the reinforcement plate. Drain the oil from the lower Oil Pan, remove the lower pan bolts and the pan. Remove the 3 bolts fastening the bottom of the front cover to the oil pan, loosen the remaining oil pan bolts for slight separation. Remove the Water Pump, the center bolt, and use a puller to remove the crankshaft pulley. Remove the piston for the timing chain tensioner. Remove the bolts attaching the top of the front cover to the cylinder head, then remove all the bolts fastening the cover to the block. Separate the upper surface of the oil pan gasket and the lower surface of the front cover with a sharp tool, replacing the gasket if damaged. Remove the distributor cap, rotor, rotor adapter, distributor housing, and the intake camshaft end cover. Remove the socket head bolts holding the upper timing chain guide, turn the engine to TDC of cylinder number 1, and keep it in this position. Remove the timing tensioner piston, unfold the sprocket bolt lock plate, remove the sprocket bolts and sprockets. Remove the 2 snap rings for the guide rail on the left side of the engine and pull the guide rail forward to free it from the chain.To install, place the timing chain and guide rail, install the guide rail snap rings, and place the chain around the lower sprocket. Engage the chain with the intake side sprocket with aligned marks, turn the intake sprocket opposite to normal rotation to tension the chain, and bolt the sprocket and lock plates onto the intake camshaft. Prevent the camshaft from rotating and torque the bolts to 6-7 ft. lbs. Engage the timing marks with the exhaust side sprocket, install the sprocket and lock plates onto the exhaust camshaft, use the distributor rotor adapter to prevent sprocket movement, and torque the bolts to 6-7 ft. lbs. Slide the chain tensioner piston into its cylinder with a new seal, install the spring with the conical end out, and the cap that retains the spring. Add oil to the tensioner rail contact well, loosen the nipple on the plug and add oil until it runs out of the nipple, then close the nipple and torque the cap to 29 ft. lbs. Turn the engine 1 revolution, recheck the timing, install the upper timing chain guide, and adjust the guide to center the chain. Before reinstalling the cover, file off flashing at the top/rear of the casting, replace all gaskets with silicone sealer, trimming off excess gasket ends. Slide the cover on, install all bolts in proper positions, coat the 3 bolts fastening the front cover to the upper oil pan with sealant. Tighten the top bolts fastening the lower cover to the upper cover first, then the remaining front cover bolts, and finally the oil pan bolts to 7 ft. lbs. Inspect sealing O-rings, replace as necessary, and ensure the DME distributor bolt has its seal and is installed with a sealer. Torque the oil drain plug to 24 ft. lbs., and both upper and lower oil pan bolts to 7 ft. lbs. Reverse the remaining portions of the removal procedures, ensuring to fill and bleed the cooling system and refill the oil pan with the correct oil.
• Timing Case Cover, Bottom
  11-14-1-703-666
  Q: How to remove and install the Timing Cover in a BMW Z3?

  A: The M20 engine in BMW vehicles is unique in that it uses a timing belt instead of the typical timing chain. The timing belt should be replaced according to specific intervals, including every 4 years, every other Service II, after 50,000 miles (80,000 km), or whenever removal is necessary for a repair. To remove the timing belt, start by disconnecting the negative battery cable and removing the distributor cap, rotor, and inner distributor cover. Then, remove the distributor guard plate (which also serves as the upper Timing Cover) by taking out the attaching bolts and nut. Rotate the crankshaft to set the No. 1 piston at TDC of its compression stroke, ensuring that the camshaft sprocket arrow aligns with the mark on the cylinder head. Remove the Radiator, lower splash guard, and belts for the alternator, power steering, and air conditioning. Take off the crankshaft pulley and vibration damper, and if applicable, remove the crankshaft hub bolt using a gear puller. Loosen the alternator bracket bolt and swing the bracket out of the way, then remove the TDC transmitter and lower timing belt protective cover. Loosen the timing belt tensioner roller bolts and push the roller in to remove the belt, followed by removing the intermediate shaft sprocket bolt and sprocket. Loosen the oil pan bolts and remove the front pan bolts that go into the timing cover, using a thin blade to loosen the oil pan gasket. Remove the bolts holding the cover and lift it off the engine. To install the timing belt, first replace the oil pan gasket and seals in the cover if necessary. Install the timing cover using new gaskets and tighten the bolts to the specified torque. Install the intermediate shaft sprocket and tension the timing belt. Install the lower timing protective cover, TDC sender, alternator bracket, crankshaft hub, vibration damper, upper Timing Cover, and distributor cap. Finally, install the accessories and belts, the splash shield, and fill the cooling system with coolant mixture. Bleed the cooling system and reconnect the negative battery cable. It is important to inspect the timing belt for any signs of damage or wear, such as hardening of the rubber, cracks or peeling of the backing, missing teeth, or abnormal wear. If any of these conditions are present, the belt should be replaced, unless it is already within the recommended replacement interval.