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can anyone help find a cure to my clutch problems.On start-up most days the clutch pedal has no pressure except for the pressure of the spring. no amount of pumping will bring it back to life,i have to either sit and wait for pressure to return so that i can then select a gear or start with pedal depressed and in gear.after a fluid change everything is ok for approx 6 weeks.the car has had slave and master cylinders(3times) and all new pipework excluding pressure switch which i will fit next week.
any thoughts? :M5eyes:
 

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BreakerBacker said:
Wow, 2 for 2 on the problems today.

My car has the same low pressure on start problem. Although it is still functional, pedal resistance is low. Thought I might start with a flush and bleed.

Greg.
I have also started noticing that there is very little clutch pressure when starting from cold!!

The clutch was replaced last year. Any thoughts on what is going on???

Steve
 

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I've notiiced for some time that I have a very light clutch pedal, not just from cold. I had thought there was something wrong, as it does slip, but only after the pedal is released. Never had it slip "in gear", only on engaging gear at higher revs and/or with throttle. This makes me think that it is something to do with the control rather than the friction materials themselves.

From reading above, it might be that the master/slave cylinder has had better days or indeed requires some bleeding.

Either way, the car is at the dealers next week to have this and my exhaust checked, so hopefully then I'll know a lilttle more...
 

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plisken said:
I've notiiced for some time that I have a very light clutch pedal, not just from cold. I had thought there was something wrong, as it does slip, but only after the pedal is released. Never had it slip "in gear", only on engaging gear at higher revs and/or with throttle. This makes me think that it is something to do with the control rather than the friction materials themselves.

From reading above, it might be that the master/slave cylinder has had better days or indeed requires some bleeding.

Either way, the car is at the dealers next week to have this and my exhaust checked, so hopefully then I'll know a lilttle more...
The pedal feel on mine is only light on the first few gear changes from cold. After that it firms up and operates normally!!!

Maybe, BMW were clever. Cold car = typical morning start. People are generally tired in the mornings, so we'll make things easier by, reducing the pressure required to engage the clutch!!!

:rolleyes:
 

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Guys...

I think your problems are heat related but this only my opinion.
Some of you seem to have a poor pedal from cold which would indicate that your system fluid is contracting when cold and expanding when warm this could be overcome by running the fluid and a preset pressure by using a pressure bleeding device and sheilding your master/slave cylinders and pipework between.
You could of course also have a leak which would not nessarilly let fluid out but could let air in when the system returns to ambient temperature I have known the flexihose to do this before.
When I changed my slave cylinder last week I noticed that the rigid metal hose connected to the slave wasn't just a straight run.I had two loops in it before it connected to the slave which you would think would create an air lock but not so...maybe this looped section keeps the fluid cool and stops the problems you guys are getting, it was obviously done by BMW for a reason...

I also noticed that the Master Cylinder is very close to the heater ducting in the footwell.I made sure that the ducting was fitted correctly and not letting any heat get to it...

Hope this helps...Let me know, Andy S,BMW, M owners GB:M5launch:
 
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