Gearbox Clutch CVs Clutch pedal not disengaging
Clutch Slave cylinder/brake pipe leak. The T25 clutch and braking system share the same resevoir located in front of the steering wheelunder the dash cowl. If your clutch is not working there is a good chance your brakes won't be either so watch it! (The T25 reservoir does have 2 sections lower down to prevent this in the short-term ~ HM)
First thing is to check if there's any fluid in the reservoir. Pull the top of the speedo panel (2 indents at the back for your fingers, its a tug!) and there is the reservoir. If its low, then you have a leak somewhere. If you just want to get it moved to work on it, fill up fluid and pump the clutch pedal up and down a few times, you'll eventually get "some" pedal feel back, but not much. Now its time to look at the slave cylinder at the back (from underneath) and check out the hard line going to it to see if its corroded away. If it's leaking, the process of pumping the pedal will have squeezed fluid out so it should be obvious where the problem is. Small chance that the clutch master cylinder has gone... but more likely to be slave cyl.
Go find the clutch slave and give the rubber boot a tug - if fluid comes out then you've likely found the main problem...
Alternatively check the fluid lines on your (elderly) vehicle. That includes the brake lines. Where there's a shared res it could be brake or clutch (sounds like clutch if nothing at all on pedal though). Another issue with the shared res is that when you've topped it up you'll need to bleed brakes and clutch, to make sure you can brake and change gear! (Whilst you should always re-check the brakes, there shouldn't be a need to re-bleed them - Ed)
Typical dragging clutch scenario
Ermie571: Anyone any ideas why, as the journey gets longer, first gets harder?
When she's cool, gear selection no problem at all. When warm, first gets very hard, but does go in. Comes out sweet as a nut. All other gears fine, apart from reverse, which makes dreadful noise (again only when hot)
HarryMann: Either the clutch is dragging when hot, or the gearbox oil is low... prob the first.
Ermie571: Have been under the van - it is hydraulic....no simple adjustment of the cable then!!
Now do I buy both master and slave? Is one more likely to be the culprit?
There is no puddle of fluid under the van, or in the footwell, and the level in the reservoir is just below max, as it has been since I bought the van a year ago.
HarryMann: No, don't - you don't know if it is either of them yet. Is one of them dripping fluid?
Ermie571: - no there does not appear to be any leaks in the front of the cab. Have not had a decent grope around, but checked the levels in the reservoir, just below the max level. Will look again when I get home. Thinking about it, every coupladays there is a tiny (5p) sized oil drip under the engine, not the gearbox. This wouldn't be from the slave on gear box, would it?
The clutch thrust bearing is breaking up inside or some other clutch operating problem has occurred inside or outside...
Has clutch been worked on in your ownership? There's a recent thread discussing clutch pipe leaks above the fuel tank are you losing fluid (master cylinder common clucth/brake reservoir under dash pod)
Outside problem 1) - Bleed the clutch system out... believe Mocki has previously said a blockage can occur as well as the normal air getting into the system due blown seals
1a) Check and top-up the master cylinder to max mark (not to top) If below max mark suspect a leak in system.
1b) Observe the clutch operating arm when the clutch pedal is being depressed fully - how far is it moving (only guessing, but at least an inch to release). If not moving much, then suspect air in system, blockage, pipe fracture or master cyl/slave cyl seal is blown.
Slave VW Part No. 251 721 263 (GSF will find their equivalent)
1c) Bleed it - either pressure bleed or bleed tube into bottle, best is to jam operating arm so that bleed action immediately forces fluid out of slave nipple > Bleeding brakes and clutches
1d) Does it work?
Yes - Does it continue working?
No - Is the operating arm now moving a reasonable amount?
Yes - Internal problem - release bearing probably No - Slave or Master cylinder problem
Inside Problem 2) Remove gearbox and inspect
Try that... others may have other insights...
Ermie571: Bled the clutch as described with auto-bleed tube, nothing to start with, then dirty green fluid came out, then clean, than no pressure. Later tested it again and clutch was working - blockage?
Bled it again as suggested - now even better...
HarryMann: This could have been a blockage in pipe/slave cylinder or the onset of clutch master cylinder problem. Regardless, sounds like the fluid needed changing and may have been very old.