These ones came from Paul not Darrin. Darrins were before this. Suspect they should be fine but will check. However...Darrin if you're reading this...;-)
DS lost her bounce
- Thread starter Pallas74
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These ones came from Paul not Darrin. Darrins were before this. Suspect they should be fine but will check. However...Darrin if you're reading this...;-)
Before you get too carried away, open up your manual and follow carefully the procedure for checking/adjusting the actual ride height of the car. It only takes that measurement to be off (to high) by about 1/2" to cause the symptoms you are describing to start to happen. That 'standard' height is adjusted by carefully rotating the HC's control rod (just slightly) that is clamped to the front roll bar in one direction or the other. A D's ride characteristics are quite sensitive to actual car ride height. Has to do with the geometry of the suspension arms.. And as stated in the repair manuals - while a fairly simple adjustment to make - the actual measurement is critical. The factory is looking for is 630mm +/- 3 mm. In 814 Vol 1 the procedure is D 430-0. Keep in mind this measurement is based on the car having 185-15 tires at the factory pressure level. If you have other tires than the that size you will need to compensate for actual diameter of the tires on the car.
If the ride height proves to be OK - then start looking for more esoteric solutions
.Steve
GDay Steve, looks like a typo 235 not 635.
OPERATION No D. 430-0 : Checking and adjusting the suspension and its controls.
111 - ADJUSTMENT OF THE HEIGHTS
In order to carry out this operation, the
vehicle must be in running order.
Place the height control lever in "normal" posiposition.
6. Check the tyre pressures : See Op. D. 000
7. Place the car on a lift or over a pit. Allow
the engine to idle. Release the parking
brake. Do not chock the wheels.
8. Adiust the front heights
Slightly loosen the clamp screw (1) securing
the height corrector control rod. Operate the
clamp in the required direction to obtain an
average height of : 235 mm +-3 mm
This measure is taken from the underside of
the anti-roll bar to the surface on which the
wheels are resting. The height of the car is
increased or decreased a s the clamp i s turned
turned either towards the front or the rear.
Tighten the clamp screw (1) (spanner 1677
(spanner 1677-T).
OPERATION No D. 430-0 : Checking and adjusting the suspension and its controls.
111 - ADJUSTMENT OF THE HEIGHTS
In order to carry out this operation, the
vehicle must be in running order.
Place the height control lever in "normal" posiposition.
6. Check the tyre pressures : See Op. D. 000
7. Place the car on a lift or over a pit. Allow
the engine to idle. Release the parking
brake. Do not chock the wheels.
8. Adiust the front heights
Slightly loosen the clamp screw (1) securing
the height corrector control rod. Operate the
clamp in the required direction to obtain an
average height of : 235 mm +-3 mm
This measure is taken from the underside of
the anti-roll bar to the surface on which the
wheels are resting. The height of the car is
increased or decreased a s the clamp i s turned
turned either towards the front or the rear.
Tighten the clamp screw (1) (spanner 1677
(spanner 1677-T).
Hi Michael,
Ya - sometimes the fingers are faster than the ol mind. However I would really suggest that the entire procedure be done from start to finish. IOW do the Pre-Height check out first (proper clearance of the adjusting rod, etc). Its all right there in same section.
Seve
Ya - sometimes the fingers are faster than the ol mind
. However I would really suggest that the entire procedure be done from start to finish. IOW do the Pre-Height check out first (proper clearance of the adjusting rod, etc). Its all right there in same section.Seve
Thank Steve/Michael. Good plan. Yes Darrin showed me this procedure on a tech day at his workshop. If I remember doing the rear involved climbing into the boot. Or was Darrin just having a laugh?? Now I just need to dig a pit.
Any thoughts as to why front drops a bit while driving and pumps up when stopped (at lights etc) in first cycle. It rises a good few inches and quickly. As though there's not been enough umph to keep her at the right level while driving.
Also back seems to have 2 positions. Lift her rear end and she drops to one position (up a bit high), push her down and she rises back to mid hub cap. When driving she seems to lift and opposite of front will settle to mid hub cap when stopped for 15 seconds or so
Almost as if while driving the fluid runs to the back then runs forward when stopped. Like driving a bath. Ok that's exaggerating!
Any thoughts as to why front drops a bit while driving and pumps up when stopped (at lights etc) in first cycle. It rises a good few inches and quickly. As though there's not been enough umph to keep her at the right level while driving.
Also back seems to have 2 positions. Lift her rear end and she drops to one position (up a bit high), push her down and she rises back to mid hub cap. When driving she seems to lift and opposite of front will settle to mid hub cap when stopped for 15 seconds or so
Almost as if while driving the fluid runs to the back then runs forward when stopped. Like driving a bath. Ok that's exaggerating!
One issue you can have with the height corrector linkage is when the roll bar moves to one side and it places sideways pressure on the corrector valve. It can bind and then overcompensate unpredictably. Lateral movement of the roll bar is set by a clamp running against the side of a plastic bush at each end, so see if you can pry it one way or the the other more than a few mm. The issue with the rear could simply be a sticky bush for the linkage, which was one of the things mentioned earlier on in this thread. Clean and lubricate the bronze bushes at each end to ensure the linkages from the roll bars can turn freely.
Thanks David. Will check and make sure all free. Start with the simple stuff!
Re: the rears - in a way he was having a good laugh - OTOH the procedure for checking the actual operation of the HC (front or rear) is to really lift/depress the front/back of the car and insure that the system settles to the same height. If not, something is amiss.
As to the 'bathtub' rocking of a D when stopping. Really depends on how hard the stop is. Under mild stopping you will get a bit. Under a panic stop a lot. Reason is the weight transfer to the front of the car and the D's very compliant suspension design. The rear brakes, while engaged, prevent the rear swing arms from moving. When pressure is released the back of the car can, at times, fall like a stone. One of the D's 'characteristics' Cit worked hard on overcoming with subsequent iterations of the system
. What I have always enjoyed doing, with my D's over the years, is - while stopped and if the car behind me is a bit to close - is push the HC lever with my left foot (LHD car) and watch the driver behind me eyes pop open as the rear of the car goes up. Typically, at the next stop, if the same car, the driver has left a bit more space between us........Quite a bit harder to do, unobtrusively, with our XM
Steve
Sorry about missing the second part of your query - I am fairly confident that when you go through the procedure(s) in the book for checking the pre- height settings as well as actual height and insuring all is moving without restriction(s) that what you are encountering will be solved. Do keep in mind that the internal slide (control) valve in the Height Corrector only has to move 1 or 2 mm before either the intake or exhaust ports are exposed. That is why, at normal or intermediate ride heights, you need the control rods end centered in the 'U' shaped cup attached to the HC slide valve. It is also why the HC's can leak so much suspension pressure if that slide valve is even slightly worn (like on the order of 0.00005" from nominal - 1/2 tenth). There 'ain't' a lot of metal to metal surface area between the slide valve and its bore to hold 1800 or so psi
minus any kind of mechanical sealing other than slide valve surface texture and fit to its bore. When new those valves should have a very, very fine satin finish to them. If they look really shinny on the edges abutting the grooves, as in polished, they will leak suspension pressure.Steve
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"Fender", Roger. You forgot "fender".:roflmao:
Hey Bill! A 'Fender' is something that goes around the hearth of a fireplace in Australia!
DON'T get me started, Adam. I have George Clinton/Parliament, and I know how to use it!! :headbang:
:jiggy::jiggy::headbang:If that don't do it, I'll introduce you to Brick performing "Dazz".
I was going to give a smartassed reply, but I got nothin'..... :disappr:
"You've got a real type of thing
goin' down, gettin' down
There's a whole lotta rhythm goin' round...... "
I can asure you the height corrector will not effect the softness of the suspension, if the car is somewhere in its height range (not the top or bottom) it should be soft, if not your new sphere have no gas, a simple test if you dont have a sphere tester is to remove the sphere as quick as possible when the engine has stopped and you depressurise the system and take note of how much fluid poors out of the little hole in the bottom of the sphere, if it is flat a large amount of fluid stays in the sphere, if the sphere has a removable damper unscrew it and push with a blunt object against the diaphram and feel how much pressure
Your are quite correct - the corrector, of and by itself, has absolutely no affect on ride quality. Its only purpose is to allow system pressure into or out of the suspension circuits based on input from the roll bar attached control rod or HC selector lever in the car. However the actual height of the car - IOW the position of the half - axles, has a tremendous affect on front suspension ride quality. If you don't believe this, find a parking lot with speed bumps in it. Drive your car over those bumps at 25 or so mph in the 'normal' ride position and then do it twice more at the intermediate settings. If you do not feel a BIG difference - and it will get progressively worse - then something is very, very wrong with the suspension set up with your car
The reason for the change has to do with a quite complex set of interactions involving the geometry of the suspension arms and position of the pistons in the suspension cylinders. Keep in mind that unless you put the car at it max height setting, the actual pressure(s) in the suspension circuit at the 'normal' and intermediate settings does not change - just the volume of fluid in the suspension cylinders changes. And the reason the factory had such a 'tight' tolerance when setting the actual front ride height of the car in the 'normal' position - which was/is 9.25" +/- 0.12" when the front of the car's suspension is raised or depressed and allowed to return to its 'nominal' position as measured from the underside of the front roll bar to the ground.
The rear has a bit more tolerance which I can only guess is due to the swing arm arrangement. Not real sure I would have liked being part of the group tasked with figuring all of this out in the 50's
.Steve
Your are quite correct - the corrector, of and by itself, has absolutely no affect on ride quality. Its only purpose is to allow system pressure into or out of the suspension circuits based on input from the roll bar attached control rod or HC selector lever in the car. However the actual height of the car - IOW the position of the half - axles, has a tremendous affect on front suspension ride quality. If you don't believe this, find a parking lot with speed bumps in it. Drive your car over those bumps at 25 or so mph in the 'normal' ride position and then do it twice more at the intermediate settings. If you do not feel a BIG difference - and it will get progressively worse - then something is very, very wrong with the suspension set up with your car
The reason for the change has to do with a quite complex set of interactions involving the geometry of the suspension arms and position of the pistons in the suspension cylinders. Keep in mind that unless you put the car at it max height setting, the actual pressure(s) in the suspension circuit at the 'normal' and intermediate settings does not change - just the volume of fluid in the suspension cylinders changes. And the reason the factory had such a 'tight' tolerance when setting the actual front ride height of the car in the 'normal' position - which was/is 9.25" +/- 0.12" when the front of the car's suspension is raised or depressed and allowed to return to its 'nominal' position as measured from the underside of the front roll bar to the ground.
The rear has a bit more tolerance which I can only guess is due to the swing arm arrangement. Not real sure I would have liked being part of the group tasked with figuring all of this out in the 50's
Steve
Thats very interesting Steve. The front ride of my car definitely varied by more than +/- 0.12", depending on something I never quite figured out. I've always thought the amount of movement of the control rod required at the HC to produce a height change is very small and that the fit of the brass pivot end in the hole effected ride and ride height. The end was well worn on my Safari, so I measured the hole and made a new end to fit nicely with a little clearance and brazed it on expecting it to transmit movement to the HC more effectively (like when it left the factory maybe) and for the ride height to be less variable. But it didn't transform things. The gap above the tyre to the wheel arch still varied by about an inch from one day to the next, and always tended to be a bit too high.
Cheers
Marc
Hysterisis! I suppose the reasons for sometimes staying a little high could include an intermittent blockage in the return line with the wire insert, wear in the rollbar bushes, balls and linkages, lateral movement of the roll bar, that sloppy pivot and the corrector being poorly adjusted or partly blocked with debris. Were all of those eliminated Marc?
The changed volume of fluid in the cylinder wouldn't have any effect. What is different as you raise the car is the angle of the suspension arms, proximity to the limit of movement and stops plus the track varies. I think the varying track may a fair portion of the explanation as at the correct ride height, a small bump would not change the track much, but as you raise the car and the track narrows, the same bump, all else being equal, would try to force the wheels apart to widen the track. Maybe, depending on the tyres, that is enough resistance to make the ride seem more bouncy?
The changed volume of fluid in the cylinder wouldn't have any effect. What is different as you raise the car is the angle of the suspension arms, proximity to the limit of movement and stops plus the track varies. I think the varying track may a fair portion of the explanation as at the correct ride height, a small bump would not change the track much, but as you raise the car and the track narrows, the same bump, all else being equal, would try to force the wheels apart to widen the track. Maybe, depending on the tyres, that is enough resistance to make the ride seem more bouncy?
I can remember changing the HC and replacing the roll bar bearings. I never investigated that return line with the insert, probably should have taken it off and cleaned it out. Just recall the front height variation issue as one of those things that I never fully resolved.
Anyway don't want to divert the thread. Hopefully the DS in question has got its bounce back by now?
Anyway don't want to divert the thread. Hopefully the DS in question has got its bounce back by now?
Tried the return line fix?
My DS23ie developed the hard front suspension recently too. With help from an earlier thread, I replaced the return line and the ride has been Citroen-terrific ever since. The return line was not too difficult to remove/replace, once the front height correcter was exposed. I was fortunate to be able to source a replacement return line but others have suggested that gently heating up the pipe (once removed from the car!) will burn out the crud lodged inside.
Good luck with the job. The memory of an efficient DS ride is what keeps us going!
Ken
My DS23ie developed the hard front suspension recently too. With help from an earlier thread, I replaced the return line and the ride has been Citroen-terrific ever since. The return line was not too difficult to remove/replace, once the front height correcter was exposed. I was fortunate to be able to source a replacement return line but others have suggested that gently heating up the pipe (once removed from the car!) will burn out the crud lodged inside.
Good luck with the job. The memory of an efficient DS ride is what keeps us 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
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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.
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.