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Discussion Starter #1 (Edited)
Went to move the M5 yesterday and the clutch pedal was on the floor (pull it up and it springs back to the floor).The car hasn't been started/moved for 6 months , so clutch fluid leak from somewhere. Looking for the clutch fluid reservoir and I can't find it . Real OEM shows one ( I thought maybe it uses the brake reservoir like some cars, but that was full). Under the car there is no sign of a leak/fluid and the pipe from the slave cyl., disappears up under the brake servo, I assume to the clutch master cyl. ?
So anybody got any clues ? ‘normal’ leak points ?<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com<img src=" /><o:p></o:p>
It’s a 6 speed LHD<o:p></o:p>
Thanks<o:p></o:p>
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Martin<o:p></o:p>
 

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Martin ,

The clutch fluid reservoir is the clear cylindrical plastic unit with a black circular plastic cap appx 2" diameter .

It will be in the engine bay towards the bulk head , just to the side of the strut top mount .

Try pumping the pedal a few times to attempt to restore some clutch function , although it seems probable that your clutch slave cylinder has failed .

D
 

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Discussion Starter #3 (Edited)
Martin ,

The clutch fluid reservoir is the clear cylindrical plastic unit with a black circular plastic cap appx 2" diameter .

It will be in the engine bay towards the bulk head , just to the side of the strut top mount .

Try pumping the pedal a few times to attempt to restore some clutch function , although it seems probable that your clutch slave cylinder has failed .

D
Thanks David,
but its not, from realoem I thought I knew what to look for as you described as well. So..........anybody got a pic ?
I've tried pumping with no results, the pedal is forced to the floor rather than stays up.
I have added the pics above & below, red car is LHD, almost the same as mine, white one RHD & you can see the reservoir just behind the header tank.

Martin
 

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I had a similar problem ( at the lights ,winter, getting dark , & raining !!!) It was a broken flange on the Clutch lever . & therefor no mechanical connect to the hydraulic cylinder . The lever "springs" to the floor when pushed & can be pulled up & stayed up till pushed again .

IT was a replace the pedal repair. (It would be possible to braise or weld the plate back on to the lever . me think ! )

Good luck

MM
 

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Take a look at your brake fluid reservoir.....

If you don't have a separate reservoir for the clutch, then it is sharing the brake reservoir through a line off of the rear corner of the brake fluid reservoir.
 

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Discussion Starter #6
Take a look at your brake fluid reservoir.....

If you don't have a separate reservoir for the clutch, then it is sharing the brake reservoir through a line off of the rear corner of the brake fluid reservoir.
Bob
You don’t sound like your 100% sure it is shared with the brakes. I did originally check it and the reservoir is full. Maybe Miles's suggestion that’s its issomething mechanical is broken needs looking into. What possibly rules that out is the the car was parked up all OK, 6 months later after not being touched the pedal is on the floor ?
Bob/Miles, thanks for your suggestions, the quest goes continues.
 

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Martin,

Looking at the red car I can tell you sure it's shared with brake reservoir...no doubt!
I'm afraid you have to look under the car, tranny most go off to check the lever pushing the clutch bearing.

Another option but I do not think it's the problem, is a complete failure of the master clutch cylinder. Or the the connection between pedal and rod to the master cylinder.....wouldn't be that simple would it?????

Willem
 

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i had same issue...in my case the slave had to be replaced (i did it myself) and it´s brand new since then.... the slave cylinder is located on the lef side of the gear box... you just have to bleed it and make it work again.

may be this...

and the reservoir is the same for the brakes....
 

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Bob
You don’t sound like your 100% sure it is shared with the brakes. I did originally check it and the reservoir is full. Maybe Miles's suggestion that’s its issomething mechanical is broken needs looking into. What possibly rules that out is the the car was parked up all OK, 6 months later after not being touched the pedal is on the floor ?
Bob/Miles, thanks for your suggestions, the quest goes continues.
The shared reservoir will not drain out when the clutch hydrolics fail, due to a safety feature of having the clutch line high up on the reservoir to prevent brake failure when the clutch fails.

If its the slave, you should see fluid leaking from the bell housing where the slave is mounted.

If its the master, there may be fluid leaking from the rod boot. But if you open the bleeder valve on the slave and give the pedal a few pumps to see if the master moves fluid.
 

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Discussion Starter #10
Thanks Guys
I had a look tonight, mechanically the pedal is operating the master with no leak inside and no fluid around the bellhousing/slave. I'll have to wait till the other half is home so she can operate the pedal while I try to bleed/look for leaks.

Martin
 

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Thanks Guys
I had a look tonight, mechanically the pedal is operating the master with no leak inside and no fluid around the bellhousing/slave. I'll have to wait till the other half is home so she can operate the pedal while I try to bleed/look for leaks.

Martin
A failed master cyl won't necessarily leak. Fluid will simply move past the internal o-rings failing to pressurize the system and causing the pedal to drop to the floor - much like a brake master cylinder failure. Bleed first (using a pressure bleeder) - but I would put money on a master cylinder failure if you're not losing brake fluid. I've had a couple of slaves fail and it usually starts with incomplete clutch disengagement - not total loss of pedal.

Note that there is a "bulkhead" in the brake fluid reservoir. Fluid is shared, but only down to a certain level. The clutch draws fluid from the back portion, the brakes from the front.
 

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Thanks for the update Martin .

It's about time that the other half started doing her share of the work on your car anyhow !

Good luck with it .

D
 

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Thanks Guys
I had a look tonight, mechanically the pedal is operating the master with no leak inside and no fluid around the bellhousing/slave. I'll have to wait till the other half is home so she can operate the pedal while I try to bleed/look for leaks.

Martin
Martin,

Did you sort this?

I have the same problem after not running my LHD 95 M5 Touring Elekta for a few weeks. Some clutch, no sign of fluid leak but pedal goes to the floor!

Is the clutch shared with the brake resevoir?<!-- google_ad_section_end -->
 

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Yes they share the same reservoir. However there's a safety that keeps some fluid on the brake side (front) in case the clutch side (back) gets low.
Your problem is most likely the clutch slave seal which lets fluid by and causes the pedal to go to the floor.
A not as common issue noted by a few users here is when the spring mechanism of the clutch pedal breaks and causes the pedal to jam.
 

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Yes they share the same reservoir. However there's a safety that keeps some fluid on the brake side (front) in case the clutch side (back) gets low.
Your problem is most likely the clutch slave seal which lets fluid by and causes the pedal to go to the floor.
A not as common issue noted by a few users here is when the spring mechanism of the clutch pedal breaks and causes the pedal to jam.
Great, thanks for your advice. Question answered.
 

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I had the same issue but changed both the master and slave so as not to be stuck anywhere on the side of the road with a failed clutch slave or master cylinder

Can't remember exactly how much but they weren't overly expensive. That was over a year ago:M5thumbs:

Hope you get it sorted:thumbsup:
 

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I had this tonight, although the car was fine this morning. Just managed to limp home thankfully. Only difference to the posts above is that my cylinder is empty - so I am thinking I have leak somewhere. Thinking about it, I did graunch the gears a few times in recent months which could have been the biting point moving low dowwn the pedal. And as I drove some clutch function did return but even with the pedal all the way down I couldnt fully disengage it.

Advice welcome. Although work is rather busy at the moment so I think it will be going to the local shop.
 

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The fluid is hydroscopic, so if function returned perhaps fluid is contaminated... the effect can be temperature dependent.

I changed mine earlier this year and it was black and definitely beyond it's prime. Was getting first gear graunching.

LHD drivers may not know that RHD vehicles have a separate reservoir so the fluid does not get changed as regularly as the brake system.
 

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Thanks UK (Ben I think ?). As the reservoir is empty a logical next step is to fill it up and see if that helps. It might at least get me to the garage, even if theres air in it somewhere. It was initially so catastrophic I'm thinking a leak or failure is more likely.
 

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I am going to throw in some of what I think is good knowledge but may be proven otherwise...

Slave and master cylinder failures are pretty common. Usually when slave cylinders fail the fluid gets past the seals and will show itself dripping from the transmission bellhousings, either from the slave itself or from the seam between the engine block and the transmission.

If the master cylinder fails it is possible for the fluid to be escaping back up past the seals and remain in the system - no leaks. However, it can also leak out from inside the car or on the other side of the firewall. Remove the kick panel underneath the steering wheel to have a good look around and feel for leaks.

If you remember a time when your reservoir had more fluid (I try to never assume) and now it has none, of course it has to be winding up somewhere so it sounds like something has surely failed.
 
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