Whilst driving through town in the V6 the other day, a sudden screeching sound could be heard from under the bonnet. A few minutes later it was obvious that the air con had cut out. On investigation I noticed that although the clutch was engaging on the compressor, the nut on the end of the shaft stayed stationary.
To gain access to the clutch the car has to be jacked up and the front RHS wheel removed, along with the plastic splash guard. once in there I found that the moving clutch plate just spun freely on the end of the shaft.
My first thought was that the nut had come loose. So with the ignition switched on and A/C selected to lock the clutch plate to the pulley I attempted to tighten the nut. It was already fully torqued.
A bit of dismantling was required to find out what had happened. After removing the nut I had to struggle a bit to try and remove the clutch plate, but when it finaly came I got a bit of a surprise. I found that the clutch hub was supposed to be splined to the shaft, but all of the splines in the hub had disapeared. There was no real swarf or metal debris, just lots of very fine rusty powder. The shaft appears to be undamaged, although there was a few spots of PAG oil from the compressor dotted about, which I presume have seeped through the shaft seal.
It looks like when the clutch was built, the nut was bottomed out on the shaft threads before it had gripped the clutch hub. The small amounts of movement between the hub and the shaft have susequently worn the splines to the point that they finaly let go. Possibly not helped by small seepages of the PAG oil, which is not dissimilar to brake fluid and attracts water. The combination of wear, rust, wear , rust has rapidly removed the splines.
Needles to say, Citroen will only supply the compleet clutch assemby including the pulley for nearly £200. Anybody know where I can get a replacement from, even from a breaker. I belive it is the same compressor as used in the V6 C5 and V6 Xantia.