BMW 21207590853 Twin Mass Flywheel

Inspect the clutch disc for wear, cracks, loose rivets, contamination or excessive runout (warping). Replace if necessary. Measure the depth of the clutch lining at lining rivets, if the shallowest rivet depth is less than 1 mm (0.04 in), replace the clutch disk. Inspect the flywheel for scoring, hotspots, cracks or loose or worn guide pins. Replace the flywheel if any faults are found. If the flywheel is removed from the engine, install using new bolts. Check to make sure the transmission pilot bearing rotates smoothly without play. Replace if faulty. Inspect and clean the release bearing module. Check the release bearing ball stud and spring retainer. Replace if damaged or worn. Clean the release bearing guide sleeve. Do not grease the release bearing module or guide sleeve. If the guide sleeve is greased, the release bearing may stick to it.

The crankshaft rear main/flywheel seal replacement requires the removal of the transmission and the use of BMW special tool 11 9 260 or one with similar effect to lock the flywheel. Flywheel bolts should be loosened and discarded and the torque plate, together with the flywheel should be also removed while the bolt thread in the crankshaft must be shaved. It is important to locate the dowel sleeve on the flywheel during the installation, and the holes of the torque plate and flywheel that belong to the torque converter. New flywheel bolts are required and for N55 engines it is recommended to align the magnetic reluctor wheel for crankshaft sensor before re-stressing of the transmission.

Remove the flywheel after removing the mounting bolts. For N55 engines, check the magnetic reluctor wheel for damage and correct orientation before mounting the flywheel. Additionally, for all engines, check the flywheel location dowel sleeve for damage and correct installation.