1999 T facelift Vectra.
I have just come back from the Alps, skiing. After the car had spent a week in the carpark, outside, in sub-zero temperatures I dug it out and off we set. Come the first hill (round the corner), 100 yards up it, the revs began to rise as though the wheels were spinning and the car stoped progressing. Put a chain on in order to move the car out of the roadway, but...
Oh no... the wheels were not moving at all. The clutch was behaving as though it had failed. Put car in first gear, lift foot off clutch and you could cheerfully get out of the car and leave it standing there, with no drive to the wheels at all.
Left the car for an hour, and came back; the same still happened.
In a shocking application of Murphy's law, when the Frenchman from the breakdown company arrived he insisted on putting the second chain on and the car drove off no problem, so he told me to use my chains. Clearly the language barrier was a problem, but the car did drive me home without a hiccup.
He told me that the clutch was cable operated and there was no such thing as an intermittent clutch problem. However, Haynes tells me that it is in fact a hydraulic clutch.
Anybody with any views, please? Did we imagine it (No; I know the difference between a wildly spinning wheel and a stationary wheel).
What could the problem be? Just cold, or something else? Is this a major problem just waiting to happen again?
Thanks
Edited by Dynamic Dave on 05/12/2007 at 18:21
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That almost sounds as though the clutch fluid had frozen - or had at least got ice particles in it, sufficient to block the return valve in the master cylinder.
I'd get the fluid changed - if it's possible to do so.
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However Haynes tells me that it is in fact a hydraulic clutch.
Correct. Uses the same reservoir as the braking system.
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Yes, the hydraulic fluid had either become extremely viscous, or had frozen completely. I don't know if these clutches have an orifice type hydraulic damper, but if so, these can cause the clutch to behave oddly when the fluid becomes viscous.
It might be worth changing the clutch fluid - I suspect it will still be running on original fluid, and it's posible that there's water in the system. One approach to this job is to bleed clean fluid through to the NSF wheel, and then run a pipe from the caliper bleed nipple to the clutch nipple, and then bleed the clutch using the brake pedal, pushing fluid back up the master cylinder. Then, finish the job by changing the brake fluid on all 4 wheels again.
Doubtlessly, someone will ask why not bleed the clutch fluid through using the clutch pedal. If so, then I suspect thy've never tried it! It's actually much easier, and much more reliable to "back-bleed" these clutches. (Don't ask me how I learnt this!)
Number_Cruncher
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run a pipe from the caliper bleed nipple to the clutch nipple and then bleed the clutch using the brake pedal pushing fluid back up the master cylinder.
If you reverse bleed the clutch isn't there a danger of flipping the clutch master cylinder seal? I've heard of that happening on brakes if the caliper piston is forced back.
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I've had clutch trouble in the Arctic but that was grease going solid in cable clutches-wonder if you've got moisture in the fluid.Cable would free up when engine got hot.
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>>isn't there a danger of flipping the clutch master cylinder seal?
There is a risk, that's true. But, I've never flipped a seal. My ex-apprentice who now has 12 years of time served Vauxhall experience has never flipped one. I'm convinced that if you are gentle, the seals don't flip. Bonus chasers and filter spinners, however, seem to flip plenty.
Number_Cruncher
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Thanks for suggestions which make good sense. Pretty certain the brake fluid has never been changed.
NC; if I run a pipe from the NSF wheel bleed nipple to the clutch bleed nipple, where does the excess (old) fluid come out from? I'm guessing there is a further bleed nipple on the clutch pedal?
Edited by Mapmaker on 06/12/2007 at 18:08
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Mapmaker
You create a closed circuit. The fluid returns to the reservoir.
Change all the brake fluid first and then do the pipe trick on the clutch.
Personally; I'd change the brake fluid and then just open the clutch bleed and let it drip out about a cupful and then lock it up.
Back-bleeding is good for air removal; but this is just fluid exchange and I'd rather have the old clutch fluid out than back in the reservoir..
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>>Back-bleeding is good for air removal; but this is just fluid exchange and I'd rather have the old clutch fluid out than back in the reservoir..
Yes, that's a fair approach.
Using the method I outline above, you renew the fluid down to the NSF caliper, then you do the clutch, pshing old fluid back up the master cylinder, then, you do a full brake fluid change; so there's clean fluid throughout when you've finished. The main risk IMO is not flipping seals, but in potential contamination of the ABS unit.
Number_Cruncher
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Pretty certain the brake fluid has never been changed.
That would be a bit scary on an 8-9yr old car!
I assumed the answers meant that while the brake fluid may well have been replaced, the clutch circuit fluid probably would not have been changed - I wonder if bleeding the clutch circuit would be part of the Vauxhall recommended brake fluid change routine?
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Why should it need to be changed? Provided the lid is kept sealed it's protected from the atmosphere. The level can be checked from the outside anyway.
I don't think the fluid was ever changed on my 9 year old Xsara, and I had the brakes burning hot once or twice on very steep, prolonged descents with no problems afterwards.
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David
The lid is not sealed; if it were the brakes could not function.
Not only is there a considerable transfer of air into the reservoir every time the brakes are applied; the hygroscopic fluid absorbs most of it's water through the rubber brake hoses.
You may have had no problems afterwards; but if, on the second application, the pedal had hit the floor because the hydraulics were full of boiling fluid - then you may have descended those steep hills rather faster than you desired.
After they had cut your bodies from the wreckage and the brakes had cooled; there would have been no evidence that there had been anything wrong with the brakes. With no skid marks prior to a heavy impact, they would have to assume that you nodded off.....
Waterlogged fluid also corrodes the cast iron of hydraulic components leading to premature replacement. Fluid is a lot cheaper than calipers.
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Actually, that makes a lot of sense.
Thanks Screwloose.
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