Problem removing clutch housing

[knightma]

I'm currently in the process of changing the clutch on my S2. All has gone well until now. I'm trying to get the clutch housing off but the reference sensor housing on the top of the clutch housing is preventing it. There are two 6mm allen key bolts holding it in place. I've got one out but the other is proving very difficult with the limited access (see picture). I'm worried I'll round the drive in the bolt head if I apply any more force to the allen key. There is a sleeve down the centre of the reference sensor housing, can this be removed and if so, does this then release the clutch housing? Has anyone any ideas either for removing the bolt or removing the clutch housing without removing the bolt. Any advice gratefully received.

 

[Indi9xx]

Do yourself a favour, buy a hex allen key bit that can be used in a socket... then hammer the bit into place, ensuring its fully home and at the same time the shock waves will break off the "stuckness" of the threads.

Even if you round out the head, its not the end... you can get a cheap 12 point socket which is internally slightly smaller than the OD of the bolt head... then when hammered over the bolt head, will be clamping down on the outside of the head... also because the gripping point will be further from the centre of the bolt head, the same amount of torque will be applying less pressure to the tool surfaces, so you can apply more force without the tool breaking free or further distorting the head... I would also recommend buying two new fasteners for when you put it back together.

Even if this does not work, its amazing how far you can lower the engine, by dropping the crossmember with a trolly jack without completely disconnecting the engine hardware (coolant hoses etc), which will give you line of sight access (with tilting the engine back as well) to drill out the bolt or use other methods even if the worst came to the worst.

 

[knightma]

Thanks for the ideas Jon, in the end I had to cut a slot through the head with a Dremel and lever the bolt with a long screwdriver. I've now got the clutch out and can see why there was so much backlash through the transmission. As you can see in the picture, the rubber has completely broken up and transfers no torque. The clutch plate just bounces between the hard stops which must be about 60° apart. I think this is the original clutch plate as everything appears it's never been touched, still not bad for 16 years and 100500 miles.