eltonjohan said:
I got under the car observing the clutch/release arm. It is pushing the pressure plate release levers, but I don't know if it should push it even further. I think it looks ok though.
I only bleeded the system with the engine off. Is it necessary to do it with engine on as well? What is the difference? The clutch feels different when the engine is running. The noise from when trying to put a gear in place must be gear tooth noise.
tochi -> does "r&r the bearings in the crankshaft " mean if I have replaced them (not that good with english short terms)? I have only replaced the oil seal for the crankshaft. cheers
You should be able to measure the movement of the throwout arm at the slave cylinder. When clutch parts are new, the movement should be 17-19 mm. If less than 5 mm, clutch pressure plate or disk need replacement. On the hydraulic clutch, there really isn't much room for adjustment, short of replacing worn parts, such as the naturally wearing clutch disc. The pushrod that is attached to the clutch pedal can be lengthened or shortened. I would guess the pushrod length could permit more compression of the master cylinder and more slave cylinder pushrod travel too. Unfortunately, at present, I do not have any specifications to offer in this regard. But, if you think the clutch is not fully disengaging, its worth pursuing. Another thought is that the slave cylinder pushrod is severely mushroomed or that the area it contacts on the release arm is severely worn. I guess if either part goes without grease for 30 years, its possible.
The clutch hydraulics should work independent of the engine and thus, I can't see why you would need the engine running to bleed the clutch. Be advised that BMW recommends pressure bleeding the reservoir rather than using the old pump the clutch pedal method. Whether this is critical on new parts is the subject of some debate. Besides, you should be able to tell the difference between a hard firm pedal and one that is mushy.
"R&R" generally refers to remove and repair or remove and replace. The nose of the transmission input shaft fits snuggly into the end of the crankshaft. On the M30 engines, the tail of the crankshaft contains inset bearings. At a minimum, these should be greased to insure smooth input shaft rotation. Because of the difficulty at removal, many just replace the bearing/s as part of any clutch work. If the bearing/s is/are worn or not well lubricated, this may result in your being unable to disengage the clutch and shift gears. It can ALSO result in noise.
As others have suggested some parts can break from first use. There are springs contained in the clutch disk that operate to dampen vibration and make clutch operation smooth. Racing clutches do not typically use these. Although they should not break, it has happened. This can result in noise, imbalance and damage to surrounding parts. I have not really given this much thought, but I wonder out loud if it is possible to install the same driven plate incorrectly so that things outwardly bolt up, but the clutch fails to work properly. Lastly, the friction material is held to the driven plate by rivets and the pressure plate has rivets too. I guess anything is possible, so maybe you have a loose rivet or too.
Having said all of this, I hope your problem is nothing more than a clutch than needs bleeding or a clutch pushrod that needs adjusting.
