There are a number of clutch related issues that can affect several of the models in the 3 series line up. So who better than replacement clutch specialist Borg & Beck to highlight three of the most common problems that technicians should look out for?
Self-Adjusting Clutch Fitment
The BMW 3 series is fitted with a self-adjusting clutch and great care is needed when fitting a replacement, particularly with regard to the three self-adjusting springs. When the replacement clutch is removed from its packaging the technician should first check that each spring is still in its compressed state (a) and has not become extended due to mishandling (b).
Some cover assemblies have a transport spider installed (c) to prevent de-adjustment and this should only be removed after the clutch has been bolted to the flywheel.
Replacing the clutch generally requires the use of a driven plate centralising tool that locates on the flywheel, the driven plate spline and the flywheel-bearing pilot bore. Tighten down the cover plate on to the flywheel evenly, while ensuring that the manufacturers torque settings are adhered to.
When the cover is tightened to the flywheel, remove and dispose of the transport spider by rotating it anti-clockwise. Remove the centralising tool and when the releaser and gearbox are re-fitted, operate the clutch pedal a few times to settle the clutch self-adjustment mechanism before starting the engine.
Moveable Release Bearing
Some technicians have queried the fact that the release bearing rotating clutch interface is loose and therefore appears to be faulty. However, this is nothing to worry about, as it is perfectly normal and a design feature to improve its performance.
Ball Race Release Bearings
Questions have also been raised about whether the plastic interface is for protection and should be removed before fitting. However, it is in fact a specific design feature and under no circumstances should it be removed, as it is integral to its correct operation.