M30 Stiff clutch

Post Fri Jan 18, 2008 9:44 pm

Bled my clutch the other day and found it to be a bit hard to press. Its an e28 m535 unit on the lighter flywheel coupled to a dogleg box.
The clutch slave cylinder is from a 1989 316i. Would this have a different bore size which would effect how much pedal effort is required? Or is there different bore master cylinders on different models?
Any help appreciated

Regards

john

Post Fri Jan 18, 2008 9:48 pm

dont you have to use an m3 slave on this conversion?

Post Fri Jan 18, 2008 10:09 pm

Dunno, the clutch works fine its just a bit stiff.

john

Post Fri Jan 18, 2008 10:12 pm

just try workin it for a bit and see if it gets any better mate

Post Fri Jan 18, 2008 10:18 pm

Hmmm not sure thats the answer mate, it feels like all the movement of the clutch is in one small section of the the clutch pedal travel. If you know what I mean.

john

Post Fri Jan 18, 2008 10:39 pm

could be a blockage or a kinked pipe/line i suppose, did you put copperslip on the bearing and input shaft sleeve?

Post Fri Jan 18, 2008 10:42 pm

Yeah I gave the shaft a smear of copper slip.

john

Post Fri Jan 18, 2008 10:43 pm

Pipe work is all brand new.

Post Fri Jan 18, 2008 10:44 pm

is the clutch plate on the right way round mate? could be a frayed cable i suppose

Post Fri Jan 18, 2008 10:46 pm

Plate is deffo on the right way around. Cable??? Its hydraulic

john

Post Fri Jan 18, 2008 10:46 pm

If it feels like its just the last bit of travel doing anything i would say you need to bleed it again.
Either that or use the proper 535 slave cylinder instead of the 316 one.

Post Fri Jan 18, 2008 10:48 pm

johnl320 wrote:Plate is deffo on the right way around. Cable??? Its hydraulic

john

sorry having a blonde moment

Post Fri Jan 18, 2008 10:49 pm

BTW it depends what your used to, my clutch is new and everything else is tip-top but it still feels pretty heavy. If youve been driving a Focus all day it will feel heavy!

Post Fri Jan 18, 2008 10:52 pm

Ritchie wrote:If it feels like its just the last bit of travel doing anything i would say you need to bleed it again.
Either that or use the proper 535 slave cylinder instead of the 316 one.

Its been bled and bled and bled, but I'll try again. Its not really the last part of the travel. sort of half way down.
Is the 535 slave the same bore though beacuase if it is then how will it make any difference to effort required?

john

Post Fri Jan 18, 2008 10:55 pm

Ritchie wrote:BTW it depends what your used to, my clutch is new and everything else is tip-top but it still feels pretty heavy. If youve been driving a Focus all day it will feel heavy!

Thats a good point, I've had a 320i for many years but I've been commuting in a nissan almera

for the last 6 months. I'll pop the misses in the drivers seat and see if she can actually press it all the way down.

john

Post Fri Jan 18, 2008 11:02 pm

Wide bore= loads of effort, no travel. Narrow bore=little effort, heaps of travel.

"Thats a good point, I've had a 320i for many years but I've been commuting in a nissan almera for the last 6 months. I'll pop the misses in the drivers seat and see if she can actually press it all the way down. "

My missus always moans when she drives my 335 and she drives a focus everyday.
Come to think of it she moans everyday.

Post Fri Jan 18, 2008 11:29 pm

Just done some home work, I didn't know the etk listed bore size on the both master and slave.
It looks like most models (plus 5 series) use a 19.05mm diameter master. The 535 uses a 20.00mm bore slave. The 316 uses a 20.64 slave.
I can't see that 0.64mm difference on the diameter is going to make that uch difference to pedal effort.
I'll bleed it again and see if that helps.

john