Stiff Clutch

[cjb80]

My clutch gets stiff to push at high revs..

What could the cause be - master/slave/air in fluid?

Thanks

Chris

 

[frank rabbets]

If it has a vacuum clutch servo that may have failed, or the vacuum reservoir.

 

[Shayne]

I had this i reverse order as well , stiff to push slow to release just randomly not all the time . Reading up on the issue and checking prices i figured either the master or slave is letting air in and for what it cost i might as well buy both parts and let a garage swap them . Took them about 2 hours i think which was a headache avoided well worth paying for .

 

[cjb80]

Thanks Shayne - It's going in for a CV joint this week, so I may as well get them to check it and do the work if that's what it is..

Chris

 

[Big Fabio]

I replaced my master and slave cylinders, bleed the system, adjusted the peddle and shifting improved. The old fluid was filthy and the slave cylinder bleeder valve was so rusted it was impossible to bleed. The job was very simple even for myself with limited mechanical skills. Shifting as improved for a couple of weeks but unfortunately I find the need to pump the peddle a few times in the morning to get into gear. From what I gather this means a leak in the vacuum system, or maybe a new clutch..

This is my first 80 series and shifting in general feels to be slow and deliberate process. Not a BMW.

 

[Shayne]

Fabio , I cured a similar problem when i changed the fluid in my 90 series by just cracking open a pipe at the master and letting it weep some while i pumped the clutch pedal .

How many 1990's BMW have been in continuous use as a daily driver and will remain so for the foreseeable future . No Cruisers aren't BMW's thankfully

 

[Big Fabio]

Shayne, I do drive a 90's BMW with 300,000 + miles... but if I had to choose I would keep the Cruiser for sure. We are in the twilight of internal combustion so you might as well drive something that puts a smile on your face, right?

 

[Shayne]

Can't argue with that , if it makes you smile then it can only be a good thing

 

[Big Fabio]

Back to the stiff clutch, or no clutch... after a bleeding session with the girlfriend pumping the pedal, and 2 more solo sessions on my back in the mud, using a cheap vacuum hand pump the damn clutch is still not disengaging. Actually broke the hand pump, so down to the parts store I went. Picked up another cheap looking pump as that was all they had. Low and behold, this pump did a Reverse Bleed. Empty the master cylinder, prime the pump, and from the slave cylinder push fluid back up into the system. Absolutely works, about 12 pumps and the master is topped off, nice firm clutch peadle and shifts smoothly every time.

 

[cjb80]

So I changed the slave cylinder today and it appeared much better.. took it for a long drive this afternoon, hit some high revs and it changed fine - no stiffness..

However I went out again this evening and the problem recurred.. ??????????????

I'll see what happens tomorrow

 

[Big Fabio]

My new master and slave cylinders never really worked properly until I did the reverse bleed. Now they are like new. It was just a pocket of air in the system.

 

[Big Fabio]

Just a quick update that may save someone a bit of clutch trouble. It turns out the problem was actually a leaking accumulator. Remove and discard the accumulator and run the line directly from the master cylinder to slave cylinder. The clutch feels a little stiffer but 100% end of problems.

 

[Dave2000]

Yep as per @frank rabbets the servo assisted brakes and clutch need to be leak free (including the accumulator) for it all to work properly.

Regards

Dave