DS lost her bounce

[kenlin]

Interesting solution you came up with Steve. Worth remembering in case we are caught out somewhere without access to a wreck to raid for a replacement. I guess owning a DS has led to many engineering innovations around the world, especially in more remote areas as people have fought to keep the D going.

Ken

Hi Ken.

Had the exact same thing happen many, many moons ago with my brake fluid 68 ID19B in 1972. Had lost a front sphere (keep in mind that in the US we did not get LHM cars until 1/69), replaced it and soon there after the car started riding a bit harder and harder. And in turn the front height keep getting a bit more each time the car was started up - as well as the car not loosing front suspension pressure, even overnight. Deducing - after taking the HC apart and cleaning that did not solve the problem, that the problem was crud from the blown sphere clogging up the return line from the HC (and boy what a mess was created when I cracked open that line). I replaced it with a line that I had made up from some steel tubing and a line tool (from Terry Keeton) that applied the 'Citroen' bump to the line end. Put on the car and problem solved.

It also made me realize that there was a some type flow restricting in that line as, now, the front of the car would drop like a falling brick when put in the low height setting . Salvaged a line from a car being wrecked (sever front end damage due to an accident) and all was back to normal - at least normal for a Cit . To sort of duplicate the factory line I plugged brazed the end of the replacement line I had originally made and drilled a 2.0 mm hole (same size as the by-pass holes in the replaceable shocks) in the brass plug. Worked darn close to the factory line. Looking back on it I should have made the hole a bit smaller, but it worked OK and just left it.

Steve

 

[DoubleChevron]

Started investigations. It'll be Thursday before I can swap the spheres. So here so far...

Car was fully down as had been in garage unused for a few days. Dropped manual control to low anyway but it didn't drop any further as it was fully down.

Couldn't wiggle the spheres at all but a quick twist to loosen one and both then could be moved around easily on their supports.

Tighten up. Started and car raised as usual. Rear in line with centre of hub and soft and bouncy. Front raised to a 9cm gap between 185/15 tyres and lowest edge of wheel arch (painted edge not inside wheel arch). Solid. Sat on front (65kg) and still nothing. Got another body on it do now 140kg and it dropped to 7cm gap. Got off still 7cm then after 15 seconds back up quickly to 9cm.

I could lift front up to 11cm and it would stay there and a push took it back to 9cm.

Engine off and drop manual lever to low and front and back drop as expected. Return pipe okay then?

I'll try removing a sphere quickly after a drive and dropping car to see if it's full of LHM next.

More soon. Thanks for all the tips.

Sounds like dead spheres to me. LHM level will not matter if the car has lifted to normal ride height.

 

[kenlin]

I'm not sure that your tests would exclude the possibility of a return line problem Pallas 74.

For my car, the front hardness gradually developed while driving and after stopping, I was able to get it to respond normally to the manual height adjuster. But then later in the day of this long trip (about 100 miles), the suspension became hard again and would not respond to movement of the manual control. I decided to drive on anyway and the suspension gradually returned to normal operation. But the next morning, the hardness returned once the car was driven.

The intermittent nature of this problem seemed to be all part of the frustration. I guess there could be times when the return blockage is thorough and constant not allowing a return to normal operation. But then at other times, a partial blockage might lead to the intermittent problem I experienced.

Good luck with it anyway. I'm sure we all share your frustration in getting it sorted.

Ken

Started investigations. It'll be Thursday before I can swap the spheres. So here so far...

Car was fully down as had been in garage unused for a few days. Dropped manual control to low anyway but it didn't drop any further as it was fully down.

Couldn't wiggle the spheres at all but a quick twist to loosen one and both then could be moved around easily on their supports.

Tighten up. Started and car raised as usual. Rear in line with centre of hub and soft and bouncy. Front raised to a 9cm gap between 185/15 tyres and lowest edge of wheel arch (painted edge not inside wheel arch). Solid. Sat on front (65kg) and still nothing. Got another body on it do now 140kg and it dropped to 7cm gap. Got off still 7cm then after 15 seconds back up quickly to 9cm.

I could lift front up to 11cm and it would stay there and a push took it back to 9cm.

Engine off and drop manual lever to low and front and back drop as expected. Return pipe okay then?

I'll try removing a sphere quickly after a drive and dropping car to see if it's full of LHM next.

More soon. Thanks for all the tips.

 

[daffyduck]

A marginally charged or compromised sphere cannot expel fluid as fast as the pump can put fluid in. Revisit the sphere charge. Swap the rears to front temporarily to prove it if you have to.

 

[Greg C]

Swap the rears to front temporarily to prove it if you have to.

Excellent idea as usual. Don't panic and do not change anything to take it away from original spec. Two things which have been mentioned before, spheres, do as Daffy suggests and that will let you know if you have to get the spheres regassed. Then height correctors. It should be a normal maintenance item after high mileage and a long time. My CX needs them done after 34 years and 500k kms, They might have been done before so I would probably halve those times at a minimum. Others may have other ideas

 

[badabec]

Hello, have you cracked the problem yet, Pallas74?

 

[Pallas74]

Hello, have you cracked the problem yet, Pallas74?

Hi. Sorry for radio silence. Lots going on and some action at the garage. I changed the spheres with no change except spraying LHM all over the engine bay. Got that under control but no go on the sphere front and the ones I put on had been pressure tested.

So, I tried loosening the anti roll bar (why not) and lo and behold. Bounce!

From there I've been to PallasAuto and stayed the day (helping!). Off with wings and suspension covers. Rad demonstrated my horribly notchy and stiff half axles and we agreed to replace with recon units. Off with everything. Checked roll bar which had no shims so essentially tightening the retaining nuts crushed the plastic cups against the bar and stopped it turning. New half axles on and Rad re-assembled and set/adjusted everything. All looking good. Car raises and sinks very smoothly - no longer up and stop and up and stop until it finally gets there. Guess that was the half axles as they were awful.

So now a massive improvement in ride. Car still getting into this slightly unbalanced fore/aft situation where it feels like the back has stuck up and the nose has gone down. Pull up to a stop and front pumps back up again. Park and turn off and front drops to this lower position again pretty quick.

That aside I'm very pleased with where its at and the car is in regular use again. Of course there are other issues but I wont bother anyone with those now (or at least not on this thread!)

One thing that came up regularly in this discussion was the return pipe from the height corrector and the small ball connector and seat. Haven't done anything with these at this time beyond the fact that I dismantled and cleaned up the front one myself many moons ago and Darrin did same with the rear one. I don't remember all those washers though (which is a worry!).

Finally anti roll bar shims - is there just one size or many. Although moving now when turned off I can lift and push down the front suspension and it just stays where its put. As though the ARB is still a little sticky. Should we have measured something, used different sized shims or anything to ensure it is free enough but properly secure?

So for now a huge thanks for all the ideas and sharing of experiences. Absolutely brilliant. Thank you!