Bleeding clutch

[Bushy]

Hi all, not been on for a while. For the last few months I have been getting clutch slip, so decided to bleed the clutch and brake fluid, as not been done for a while, but with wife in car pushing clutch pedal there was resistance for first few depresses and then nothing, pedal just springs to floor and then needs pulling up.  Hardly any fluid is exiting the nipple. Am I to assume the slave needs replacing. The previous owner had clutch replaced about 20k previous to now? Or does this need to be pressurised to force the fluid out at the reservoir?  Sorry if this has already been answered but I'm at a loss as to what to do, as car now has no clutch! Neil

[insanitybeard]

If you're getting clutch slip as opposed to drag then it's more likely to be a clutch friction disc wear or pressure plate issue than an issue with the hydraulic side of things, unless the slave cylinder isn't releasing pressure (due a fault in the hydraulic side of things) when you let your foot off the pedal causing it to counteract the spring pressure of the pressure plate, but this kind of fault is unusual, at least I.M.O.

As for clutch bleeding, how are you doing it? A length of tube into a jam jar or something like that? I've always found hydraulic clutches to be funny things to bleed, even when vacuum bleeding the pedal is still crap initially but improves when you work it a few times, if you're just bleeding by getting somebody to pump the pedal manually then my approach would be to crack the bleed nipple off only a small amount, ensure the reservoir is topped up at all times so there's no chance of air getting into the system and pump slowly, releasing the pedal fully each time, then when you go to tighten the nipple back up, ensure the person pumping the pedal keeps it held fully down to the floor until you've tightened the nipple up to prevent air being drawn back into the system.

If the clutch pedal isn't returning by itself when you pump it then that would indicate to me either 1) a blockage in the hydraulic lines somewhere preventing fluid flow/ return, 2) the seals in the master cylinder having failed or 3) an airlock, you could try closing off the nipple and pumping the pedal vigorously and seeing if that helps.

Was the slave cylinder renewed when the clutch was replaced? And what about the dual mass flywheel for that matter?