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Help! - Clutch pedal pressure loss...

36K views 18 replies 13 participants last post by  dossbag 
#1 ·
Evening all!

Driving home yesterday on the motorway, the clutch pedal suddenly became very light. Still managed to change gear ok got it home. But took it out again today and after about 5 miles the pressure on the pedal went and it was very difficult to get into gear....

Limped home, opened the bonnet. Now the small pipe seems to come up from the pedal cylinder, it goes straight through the bulkhead and across the front, down into the gearbox housing.

Q's!! - I can clearly see two bleed nipples, one is at the front about 4" below the windscreen, the other on the master cylinder on the gearbox - how do you 'top up' the fluid levels??? There seems to be no resovoir?
Suggestions are that it is connected to the brake master cylinder in some way, but I just cannot see it?
Is there a tool to 'pressurise' the pipe, akin to the old Mini hydrolastic set up?

Or do I just assume one of the cylinders has gone? I thought about taking the centre union apart and screwing in a bolt, lightly pushing the clutch pedal to see if I can build pressure - is this a good way to test the pedal based cylinder?

It's a 2.4D 1995 model with absolutely no visible leaks of fluid at all. I have a theory it may be the master cylinder into the gearbox, but how do you refill the fluids when you change it?! Incedentally the brake master cylinder seems absolutely fine...
Van on 195,000 miles, please, if anyone can help with this I would be very grateful! :)
 
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#2 ·
Hi not sure if this will be helpful but hopefully it might. I have a 1.9td on a t plate and had trouble with my clutch the other week.
From what i read and found when poking about the clutchs on these vans are either cable operated or hydraulic.
Your right in saying that the clutch share's the same resivour as the brakes.
The master cylinder is located on the pedal and operates a slave cylinder on the gearbox.
From what i have read on some models the slave is inside the housing of the gear box but if its like mine its bolted to the side of it. A common fault is the pedal box becoming weak and braking near the master cylinder i believe there is a fella on here who can repair them. My problem was a faulty master cylinder the pedal was working but gradualy creeping to the floor. I replaced it and bled it through with fresh fluid. Bleeding it was just a matter of having some one in the van to operate the pedal and cracking the bleed nipples much the same way as bleeding the brakes. as far as i know and from my experiance from last week the system pressurises its self.I am sure some one will correct me if this is wrong. Hope this might helpT:
 
#3 ·
Hey, thanks for taking the time to reply!
Mine is hydraulic - but there just seems to be no clear connection between the brake pipes and clutch pipe?
... Unless I am missing it, traced it back several times - I guess it will need fluid from somewhere.
I think I need a better look!

My slave cylinder is located on the side of the gearbox.... Can I ask how you found out which one was at fault?
I did think about disconnectng the pipe at the union below the windscreen, putting a bolt in it's place and just seeing if I could build a very slight amount of pressure at the pedal?

Or is it worth maybe replacing the master cylinder anyway? GSF seem to have them at about £46 so not too desperate money wise...
Thanks a lot for the reply - oh, and not a cracked pedal mounting, it's very firmly in place so this can be ruled out, although may be worth upgrading to if they are that problematic... :)
 
#4 ·
Hi thats ok mate. From what i read the resevoir is actually split in to 2 compartments on the inside. There is a big'ish hose that comes off the master cylinder and goes through the bulk head to the resevoir. I am not sure about the bolt option but it may work. I checked all the pipes from the gearbox back for leaks then blead it through starting at the nipple below the windscreen wipers then down at the slave cylinder. this didnt cure it so the only options left where the master or slave being faulty or worst case scenario the preassure plate/clutch. i stuck my head back in the foot well and noticed a slight leak round the top of the plunger from the pedal in to the master so thought i would start there. I got mine from gsf and touch wood it has cured it. Hopefully yours may be the same. When i asked about it on here every one said it would be a pedal box so thought i better mention it. master cylinders seem to be pretty common on here and its only 2 bolts and 2 pipes to remove.
 
#5 ·
Hi

The brake reservoir does indeed supply the clutch system.
The reservoir is not split into two sections, however the clutch hose takeoff is considerably higher on the reservoir than the brake takeoffs. The reason for this is that if you loose brake fluid then the first thing that stops working is the clutch! Sound familiar?

My advice is to check your fluid level in the reservoir, if it is low, top it up and then bleed the clutch through the bleed nipple below the windscreen. Top it back up to the correct level and keep a close eye on the level if it drops then you have a leak either in the clutch system or the brake system.

I'm the fella who sorts pedalboxes by the way if the pedalbox has failed get in touch.



Cheers Trev.
 
#6 ·
Great! Thanks for the responses, sounds as though I need to really carefully examine everything again. - Check for leaks inside and so on...

The brake fluid is topped right up, I guess a bit of air in the system is entirely possible so worth bleeding first.
I will have a look at it again in daylight and update... Good to know that people here are willing to help, very grateful. :)
 
#7 ·
same happened to mine few mths back, low on brake fluid, topped that up and bleed clutch pipe just in case and problem sorted. just dont know which one sorted it, lol. if u have a little fluid around cyclinder at the peddle then u are probabley sucking in air causing pressure loss.
 
#8 ·
In the process of doing mine on a 95 2.4D, the slave is on the back of the gear box connected by a flexible pipe which on mine had rubbed and started letting in air. The slave is held on by 2 13 mm bolts, check this is not leaking as it will contaminate the clutch plate. The master cylinder is on the back of the pedal if this is leaky you will have fluid on your pedal. T:
 
#9 ·
i've just had similar happen to my t4 52 plate 2.5 tdi, but mine isn't the one that bolts on the side, it's in the gear box (centric or concentric or something) is this a big job to put right. what are things i should be looking for? went from having a good clutch to nothing in the space of about 15 minutes of drivind!
 
#11 ·
Bleeding it wont fix a leak, you may be lucky and find its leaking externally, maybe from the bleed nipple or a pipe, if the fluid it coming from inside the gearbox then the slave cylinder will need replacing which will be pricey due to the labor involved.
 
#12 ·
Yeah, sort of resigned to worst case scenario, but will get under there and check for any loose unions, dripping nipples(!), etc. before shelling out £££.

Still got a bottom end rattle around 1200rpm (under load) to sort out as well - wonder if related in any way? Already eliminated damper pulley, exhaust heat shields and anything attached to the Aux Belt. Next step was sump off to check the state of the bearings.

At this rate I think I'll be taking her off the road for a while and pulling the whole lot to bits - so many issues :-(

Lucky I have no trips planned this summer yet
 
#18 ·
Hi I've had a problem with my clutch pedal biting point going from half way down to about inch of the floor all of a sudden. So changed clutch pedal master cylinder and slave cylinder and bled it but clutch pedal is still soft and biting point is couple inches off the floor. Any help appreciated please.
 
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