Technical Clutch Pedal

[kmbenno]

Help need please,

I had a new clutch fitted as i thought mine was going. Anyway, after that the clutch pedal started to squeak and stay down occasionally, quite difficult to set off in 1st.
So we took it back and they said it was a hydraulic pipe, which they repaired. So this weekend we went away again, just an hour away, and all was fine until we left the motorway, then the squeak started again, and then eventually the pedal stayed down on a small road, really not good.
A very kind farmer offered to tow us to site which was only 2 miles away, anyway by the time we had hitched up and was ready to go, the pedal came back up and we continued with no problems.
Then on our way home the wife found something "the hot air blow on the feet area in the cab" makes the clutch stay down and squeak.
During the journey home having had the heater on the full journey, it started again, after the wife's find, i turned it off and it stopped
Has anyone else had this and if so how did you repair it ?

We need to start longer journeys please help

 

[Anthony489]

Hi

Modern clutch pedals often have a small coil spring near their pivot. It is arranged with an "over centre" action, in other words for the first part of the downward pedal movement it acts upwards to return the pedal, and for the second part of the movement it acts downwards to push the pedal down. The idea is to give a lighter clutch pedal action. With just this spring, once pushed down the pedal would never return, but there is an additional stronger force from the spring fingers in the clutch (acting back via the hydraulics) which is enough to do this.

It's possible that the pedal mechanism lubricant has dried out, exacerbated by the warm air going past it. This might just increase the friction enough to prevent the pedal returning. Incidentally, if you get caught in this situation you can sometimes just lift the pedal with your foot, or by hand if parked.

Unfortunately, this behaviour can also be the sign that all is not well with the clutch master cylinder or the slave cylinder. The latter is buried within the bellhousing, was it renewed when the clutch was done ?

 

[Communicator]

Hi

Modern clutch pedals often have a small coil spring near their pivot. It is arranged with an "over centre" action, in other words for the first part of the downward pedal movement it acts upwards to return the pedal, and for the second part of the movement it acts downwards to push the pedal down. The idea is to give a lighter clutch pedal action. With just this spring, once pushed down the pedal would never return, but there is an additional stronger force from the spring fingers in the clutch (acting back via the hydraulics) which is enough to do this.

It's possible that the pedal mechanism lubricant has dried out, exacerbated by the warm air going past it. This might just increase the friction enough to prevent the pedal returning. Incidentally, if you get caught in this situation you can sometimes just lift the pedal with your foot, or by hand if parked.

Unfortunately, this behaviour can also be the sign that all is not well with the clutch master cylinder or the slave cylinder. The latter is buried within the bellhousing, was it renewed when the clutch was done ?

The change to a concentric master cylinder inside the bell housing, was only made with the introduction of the x250 model in 2006. My 2006 x244 has an external master cylinder.

 

[Communicator]

The change to a concentric master cylinder inside the bell housing, was only made with the introduction of the x250 model in 2006. My 2006 x244 has an external master cylinder.

I was thinking about having replaced the master cylinder when I wrote. In post #3 quoted above for "master cylinder", please read Slave cylinder".