[s-cars] Bleeding hydraulic clutch line - possible mistake? (long)

[Sean Douglas]

Dave:

Sounds like you are OK. The gooey black sludge is a sign that the slave
cylinder has never been bled.

I ran into the exact problem, when I replaced my clutch master, couldn't
get any fluid to flow from the slave bleeder with my Motive pressure
bleeder until I pressed the clutch pedal - then it stuck to the floor as
you described. I managed to pull the pedal back up and bled some more.
Everything seems to be functioning allright.

Sean

> -----Original Message-----
> From: s-car-list-bounces at audifans.com 
> [mailto:s-car-list-bounces at audifans.com] On Behalf Of Dave Ellis
> Sent: Saturday, November 05, 2005 3:15 PM
> To: S-Car-List at Audifans.Com
> Subject: [s-cars] Bleeding hydraulic clutch line - possible 
> mistake? (long)
> 
> 
> 
> So I decided to bleed the brake fluid on all four corners as 
> well as the 
> hydraulic clutch lines on both my Audis today.  It's been two years 
> since I last did the A4 and this was the first time for my '93 S4.
> 
> So I pull out my Motive bleeder and three litres of Pentosin, 
> and go at 
> it.  The A4 went smoothly (even bleeding the clutch line is 
> easy on it), 
> and then I moved on to the S4.
> 
> I've owned the S4 for two years, and just did the brakes last month. 
> The original owner had the brakes done at the local Audi dealer just 
> before I purchased it, and so I figured the brake fluid would 
> have been 
> flushed at the same time.  Apparently I was very wrong in 
> this supposition.
> 
> The rear passenger and front driver's side lines yielded dark brown 
> fluid with a worrying amount of small particulate matter.  
> The other two 
> callipers/lines were not too bad, though the brake fluid was 
> noticeably 
> dark.  When it came to bleeding the clutch line, I ran into problems.
> 
> First off, I'd just like to say what a @$%&^&! pain in the 
> a$$ it is to 
> bleed the hydraulic clutch line on the UrS4.  Getting a 
> wrench up to the 
> bleed nipple and then finding room to manouver it is quite a 
> challenge. 
>   The A4 crowd keep complaining about how hard it is to bleed 
> the clutch 
> line on that car, but it's dead easy compared to the S4!
> 
> When I did finally manage to get a line over the bleed nipple for the 
> clutch from below and loosen the screw, no fluid at all 
> flowed.  So with 
> my wife helping from above, she raised the pressure first 
> from 5psi to 
> 10psi, and then finally to 15psi on the Motive bleeder.  
> Still no fluid 
> flowed.  Loosened the bleed nipple more (there went some more 
> skin from 
> my knuckles), but still no fluid.  Hmmm...
> 
> I ask my wife to press the clutch pedal, and I hear a loud 
> *snap*.  Uh 
> oh.  My wife tells me the clutch pedal was stuck, and when 
> she pressed 
> harder it suddenly dropped to the floor.  But at least now fluid is 
> flowing out of the bleed nipple.
> 
> I don't think from the look of the fluid that came out the 
> clutch line 
> had ever been bled.  What came out was black sludge full of mud and 
> other unsavoury goo that had little resemblance to any brake 
> fluid I'd 
> every seen before.  As I watched the mess make it's way down 
> the drain 
> tube I couldn't help but think I should have noticed some 
> problem with 
> the clutch pedal feel with fluid in this condition, but never did.
> 
> Eventually once the fluid was running clear I closed 
> everything back up 
> and went to move the car off the ramps I had it up on.  I get 
> into the 
> car and find the clutch pedal on the floor.  Not good.
> 
> I raised the pedal back up by hand against some resistance, 
> and was then 
> able to pump it up and down a few times until it felt 
> "normal" again.  A 
> quick drive around the block and everything seems good.  
> Brake feel is 
> nice and solid (better than before), and clutch engagement is 
> now *much* 
> improved (and very different) than I ever recall it being before (go 
> figure)!
> 
> So to end this saga with a question, have I damaged either of 
> the clutch 
> cylinders?  Is it normal for no fluid to flow until the 
> clutch pedal is 
> depressed when bleeding the clutch line?  Any comments or insight is 
> welcome.
> 
> Slightly worried,
> -Dave
> 
> 
> 
> 
> _______________________________________________
> S-CAR-List mailing list
> S-CAR-List at audifans.com 
> http://www.audifans.com/mailman/listinfo/s-> car-list
>