Having written here previously about the moving biting point on my 43,000 mile 2002 model C5 2.0 HDI 110, and the dealer finding nothing wrong while in warranty, I feel the symptoms are getting worse now.
When holding the clutch down for any legnth of time, say 5 to 10 seconds, while the engine is hot, the biting point moves so that the slightest movement of the clutch makes it bite. A few more presses of the clutch, say 1st to 2nd gear, and 2nd to 3rd while moving, and the clutch feels normal again.
There is no slippage and I do not 'ride' the clutch, I match my gears and revs well when changing, so I am sure there is minimal wear to the friction material.
Having inspected, and the garage done the same, there is no fluid leakage.
I have obtained prices for the master and slave cylinders to be replaced, the master is a very long job, taking about 3 hours, the slave is well under an hour.
Do you think this is definatly the master, or is it worth changing the slave first to see if it makes a difference?
Thanks in advance
Ben
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See HJ buyers guide ,your lucky to have done 43000 miles,the clutch is on the way out.
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If 'pumping' the clutch pedal resolves the problem then it could well be air in the hydraulics.
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The garage discounted the problem being air in the hydraulics because the pedal doesn't feel springy when you press it. The pedal feels firm at rest.
I have spoken to Citroen head office and they say their computer does not show any known issues with C5 clutches. The CBCB shows differently I know.
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I've done 51,000 and the clutch is as good as new....
(Now wots that sweet sickly smell all of a suddden?)
Can't say I've heard of any complaints about C5 clutches on the forums, although I did come across problems with Peugeot units (presumeably the same) I've a feeling the hydraulic clutch system is a complete unit - ie master + pipework + slave (closed system) and is replaced as such. Not certain on this though - can anyone confirm?
Could it be a sticky release mechanism in the clutch itself?
I would have expected certain Peugeot faults and Citroen faults to be identical, but doesn't always seem to be true. EG Peugeot HDIs have a reputation for crankshaft pulley failure - yet I haven't come across this on Citroens - with the same engine!
Graeme
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The garage discounted the problem being air in the hydraulics because the pedal doesn't feel springy when you press it. The pedal feels firm at rest.
I have to disagree. I have worked on many a hydraulic clutch over the best part of 30 years. Air does not necessarily make the pedal feel springy in the way that it does in a brake pedal. In a brake pedal there is little movement of fluid through the system and you are working against a non-compliant load (the disc). With a clutch, there is a lot of fluid flow and you are working against a spring.
Often, in my experience, you only know that air is in the system because the 'throw' of the slave cylinder push rod is less than it should be (the air bubble is slowly compressing as the load increases). This manifests itself as the clutch failing to clear properly. In fact, not so long ago, I had a grumble about a gearbox with notchy change that was down to air in the clutch hydraulics. Because of the valving in the clutch m/c (which a brake m/c doesn't have) pumping the clutch pedal tends to restore proper operation for the moment.
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As the master cylinder is above the slave and at the top of the system, wouldn't air eventually be expelled by pumping?
Do you think that bleeding the system or replacing a cylinder is the cure? I do not want to replace the master, as it is 3 hours labour charge.
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As the master cylinder is above the slave and at the top of the system, wouldn't air eventually be expelled by pumping?
No. A lot depends on the angle of the pipe and the slave cylinder etc. I have had a lot of problems bleeding clutches in the past - they can be much harder to bleed than brakes.
On Mercs I always remove the slave cylinder and let it hang vertically to that the bleed nipple is at the top - otherwise they don't bleed.
Audi's were always very awkward too - impossible without a pressure bleeder.
The usual DIY technique of bleeding by pumping the pedal and opening/shutting the nipple is not very effective on clutches. Either use an Easibleed or MityVac. Some folks favour 'reverse bleeding' where the fluid is forced in through the slave cylinder bleed nipple.
Do you think that bleeding the system or replacing a cylinder is the cure? I do not want to replace the master, as it is 3 hours labour charge.
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Unless you have a leak I would not replace anything. I would rebleed the system. It may take half an hour or more. It there any way you can measure the throw of the slave cylinder or release arm? And then compare it with manfrs specification or a known 'good' car of the same type.
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Bleeding the clutch would take a very short period of time ,if it does not cure it you need a new clutch.The symptoms are exactly the same as on my first C5 a new clutch the pressure plate was worn out and the clutch plate was ok as HJ vehicle reports.
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I had very similar problems on a Triumph 2.5PI where the slave cylinder was about 2 feet below the clutch master cylinder. As Aprilia describes, I eventually removed the slave cylinder and tubing so it was as high above the master cylinder as possible - and left it suspended for about an hour - for any bubbles to move up. Then bled it slowly (the slave cylinder was tied so the rod and seals would not pop out). After about 3 hours - mostly going away and leaving it, it cleared the problem.
That was after replacing clutch, slave cylinder, master cylinder, release bearing and clutch operating forks:-((((
Fortunately DIY. But the gearbox and overdrive was HEAVY..
madf
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I agree entirely with Aprilia; venting clutch systems can be difficult, generally because the slave cylinder has a compliant mechanical load, unlike a braking system. Sometimes the pipe runs also conspire against easy bleeding. My (pet) Swedish SAAB has an annular hydraulic slave cylinder with no lever, which is quite impossible to bleed by operating the pedal.
The job is easily done by pressurising the reservoir with a foot pump and simply opening the bleed nipple. The necessary adaptor is fabricated from a spare reservoir cap and a piece of inner tube with the valve in it. If you cut a hole in the centre of the spare cap and cut a circle of rubber around the valve stem such that the assembly fits neatly inside the cap with the rubber disk forming a pressure seal, bleeding is dead easy.
659.
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Bleeding the clutch would take a very short period of time ,if it does not cure it you need a new clutch.The symptoms are exactly the same as on my first C5 a new clutch the pressure plate was worn out and the clutch plate was ok as HJ vehicle reports.
Maybe I'm missing something - or something really weird is going on - but I can't see how a defective pressure plate would cause the bite point to vary.
I have changed loads of clutches over the years and seen cracked and worn diaphragm springs, broken rivets, broken fingers etc. - however the bite point would be 'stable' (even if 'wrong'). I am convinced it is a fault with the hydraulics.
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The pressure plate sticks in various positions due to its gradual disintregation
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The pressure plate sticks in various positions due to its gradual disintregation
Sounds expensive.
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The pressure plate sticks in various positions due to its gradual disintregation
Never seen that happen, but I agree it could be what's wrong. Citroen are known for their innovation!
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Is that a clutch replacement job?
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Thanks to everyone who has posted, I'll let you know what the dealer says in 2 weeks when it goes in.
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I'm really sorry, I didn't reply!
The dealer said the clutch is fine, now 7 months later the clutch has started slipping in 4th and 5th gear at around 2,000 revs, but the slippage stops at around 2,500rpm.
Just why does the C5 require 7 hours labour to change the cluch?
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Lots of bits to disconnect/remove before you get to the clutch itself. Then you have to put them all back again.....
On the old XM's my mate who runs an auto transmission rebuild 'shop reckons it took about 20 hours to remove and refit the transmission! He hated doing them because they tied up a lift for a couple of days.
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