Citroen XM Forum

Does the body of the governor rotate in use, if not, I would suspect the seals are being trapped during assembly.
it would probably be worth using a seal guide when installing the governors. I piece of OHP acetate film would do. Wrap the seals, install, slide out the protection sheet.

I used Vaseline to secure the seals at the last fitting Will and that was about 20,000 miles ago, so I think the rubber has just worn out. The seals were also not new as the governor was borrowed complete from the cobalt car. With regards, Matthew T.

The governor body rotates in its bore and is connected directy to the final drive through the diff, no ring compressor tool can be used as the bore it slides into is a blind hole and the head of the governor is twice the diameter of the seals which obstructs access and view of them when fitting in, the bore does have a chamfered edge however to stop the seals pinching on assembly but care must still be taken.

I was under the impression the valves that are centrifugally operated by the motion of the governor bled pressure away from a line when stroked open to the exhaust position with increased road speed, there are no ports to return this fluid to the valve block and it is dropped into the transfer case and differential case to lubricate these components when moving, the faster you go the more valves open in turn and the more lubricant is fed into these components which would be a good use of oil, if this is the case then you would need a damaged oil filter for debris dropped into the sump from the governor to be drawn back up and into the valve block.

I cannot think of anywhere else in the box where there would be a rubber seal that could enter the valve block.

D

I concur with your comments about fitting the governor Dean and all the guidance I have seen is to liberally coat with Vaseline, which holds the seals secure in their groves and reduces friction. In relation to the oil, my mechanic advised that any debris from the governor can be distributed around the system as the oil is constantly circulated throughout. With regards, Matthew T.

I have also now checked the governor internals that were free of debris and also removed the steel ring. Interestingly the steel ring is also heavily worn with quite a significant reduction in the diameter compared to a new example. The inner (to gearbox) rubber ring is slightly reduced overall but the surface is also badly scored and irregular where material has been removed, which I assume is just down to wear. My experience queuing in heavy traffic for more than an hour and the quite extreme heat that caused the initial loss of drive must have been a factor. I attach slightly better general and detailed photos for further explanation and in the first photo the new rings are on the right. Regards, Matthew T.

Further to my last message some of the replacement metal rings that I have which originally came in sets with rubber rings seem to be larger than the correct spec. although fortunately one is okay! The original metal ring therefore appears to be only slightly worn and I hope the severely depleted rubber ring is the cause of my woes. I shall also check the governor cylinder for wear before refitting. Regards, Matthew T.

I refitted the governor this afternoon, but sadly drive is not restored. If I am honest, I was a bit doubtful the governor was to blame and that one worn seal would have such a big impact. On the earlier occasion when I nipped the same seal when fitting the car was still mobile. As I still have access to the valve block I may quickly try my spare, just in case I missed something, otherwise I guess it will be engine and box removal no.5! Perhaps I should be grateful I have enjoyed 25,000 almost trouble free miles including 2,500 around France. If anyone has any other ideas as to the likely cause of the issue I would be pleased to hear further. Regards, Matthew T.

I take it there were no funny noises from the gearbox, it just lost drive, is there anything in the filter?
I am still wondering where the rubber parts came from that were found lodged in the C clutch accumulator, did you remove and inspect all of the valves in the block and blow through the oil galleries?

D

There have been no noises that I am aware of Dean and the oil and filter were basically clean apart from some very light metal residue and a few other pieces of rubber. The rubber found in the valve block and oil certainly looked like bits of governor seal. I did remove all the valves and split the block but there may have been something I missed. With regards, Matthew T.

By 'oil galleries' I assume that you mean the maze of channels in the centre of the valve body Dean that I did carefully check for debris. The oil and filter were actually very clean and the only residue was on the drain plug magnet and what settled in the basin used to collect the oil. There was also no significant discoloration in the oil or nasty smells to suggest overheating or burnt clutches. I am wondering whether there are any other critical seals elsewhere in the gearbox that can fail and cause loss of pressure and engagement of all gears? Regards, Matthew T.