J2 CXM

[raynoon]

1993 2.1SD auto, ETK Tempest, RP6043


I don’t believe I ever introduced my latest XM, here she is, a slightly scabby dirty 1993 2.1SD Auto,

81C243FA-8630-445C-8351-C5D36AB15B8C.jpeg

Acquired earlier this year from County Durham, we had a slightly knobbly but otherwise uneventful and relaxed journey home, I really cannot stress how well this car drives, even for an Auto. She’s smooth, rapid and economical.

E392B5D1-9516-47AE-BFC3-5085C56CE017.jpeg

So much so, before my diagnosis, I had planned on selling another car to raise money for a full body refurb/respray.

CA2F6F6E-45B5-4002-9E98-A364ED1D5986.jpeg

Her previous keeper had owned here for a staggering 17 years, he was an engineer and looked after her mechanics and electronics. He had started practicing on the bodywork, hence her shabby appearance.

First job on the list was cleaning.... she had sat under a pine tree for the best part of a year, covering very few miles between MOT’s and to this day I’m still finding pine needles. She didn’t come up too well, My plan was to run her until she died and use her for parts, the sunroof worked perfectly and the autobox was excellent. So I ran her. And ran her.

The knobbly suspension was proving a bugbear, I decided to try and change the centre spheres my self, but again the front centre proved problematic accessing (Ive tried changing them on 4 of my XM’s with only a 50% success rate) no luck there.

I had a quick look in my pile of spheres, no Xantia non hydractive but a set of CX spheres... dare I? I dared!

I’ve been driving it like this for almost 5 months now, and it hasn’t fell over yet. There were some initial adjustments to be made, she would hit the bump stops on the biggger speed humps, but if I move the height control lever about 1cm up into high on the approach everything is glorious. It’s so wonderfully soft even at motorway speeds, there is no uncontrollable wallow, she just glides.

Her previous keeper has also installed an upgraded sound system, a nice modern Sony with USB and steering wheel controls. I installed a sub and amp in the boot just to provide a bit more depth to the bass, no window rattling boy racer bass, just depth and clarity.

Her texton alarm still works perfectly, and I’ve also grown fond of the 24V alloys that she wears.

I’m unable to drive at the moment and I’m missing her terribly. I’m also unable to sleep properly, my brain won’t shut down for sleep, so I decided to try and let some of the thoughts escape into text. I hope you’ve enjoyed reading this chapter as much as I’ve enjoyed writing it.

I’ll be back with another update soon.

Ray.

[White Exec]

Sometimes, a good bit of writing can be really therapeutic!
EVN is obviously determined to keep you in good spirits, and provide a bit of entertainment along the way.
Interesting to discover what a soft CX sphere will do!

[russ92xmsed]

Very interesting to hear about the Cx spheres, I remember you saying something about those at chevrons.
Hopefully you will be back driving her soon Ray.

[djg]

I plan to switch to C5 spheres. Same characteristics, larger membrane diameter, nicer drive. My mechanic has those and it's really good. It fits without any modifications.

[russ92xmsed]

I'm surprised. Would have thought they wouldn't fit under the scuttle. Interesting to see how you get on with them.

[White Exec]

Will be interesting to know the specs of the spheres you choose, Gabor.

[djg]

Last time we spoke about it he mentioned the specs being the same, same volume. Only that the C5 ones are more of a pattypan squash than our eggs, the membrane is larger and gives a softer ride. I haven't driven his but already rode shotgun, and it's nice.

Actually, Chris, come to think of it, it's a white 2.5 Exec. Unlike you, he doesn't like white but black but this was the one he was able to find at the time with healthy internals. Both 2.5 and Exec were absolute requirements, though, with both leather and sunroof.

[xmexclusive]

I think the big difference is on membrane edge fixing stress.
For this you compare circumferences and not diameters.
My estimate is that the sphere diameter increase reduces edge stress by around 50%.
So for a particular service life the C5 membrane will have only done half the amount of bending.
If this is so it is the worst half of the bending that is eliminated.
So I think we could expect membrane working life to increase by a factor of between 5 and 10.
Increased membrane area may fractionally increase nitrogen percolation losses.
I would expect the membrane to be of the latest design to offset this.
Extent of nitrogen percolation may well be mainly related the heaviest flexed areas of the membrane.
There is a problem in recharging C5 spheres but the above suggests it might not be a frequent requirement.
Clearance for the extra diameter needs careful checking for each location.

John

[Dieselman]

I thought C5 spheres were only 375cc, not 400cc or even 450cc of H2 cars.
As a result, C5 spheres give a less supple ride.

If you want a really wafty ride fit 500cc spheres with 0.9mm centre hole.

[djg]

It's possible that he had some other modifications, too, I'll ask. He was always able to soften up an Xm to significantly above and beyond factory levels with careful matching of available Citroën parts. The front strut spheres are definitely C5 in his car now.