Need Xantia Eggheads Help to Diagnose Stiff Ride!

[seany87]

Hi, I have a 2000 Hdi 90.

Recently I had a leaky pump. This was replaced about 1 month ago by myself from a similar scrapped Xantia, and lo, everything was perfect. For the first time I experienced the magic carpet ride, like driving on glass, I was really chuffed with it.

However, within the last week or so, the ride was reverted to being quite harsh, something akin to when there is a lack of LHM in circulation.

I suspect air in the system but I want to explain some of the symptoms to you in case I have missed anything obvious...



-All corner spheres were replaced about 10k miles ago, Im 75% sure the accumulator was done at the same time.

-Since the pump was replaced there has been no more leak (yay) but I think I have overfilled the reservoir, will this effect the ride? I think also the belt could do with tightening a little as it squeaks.

-If I leave the car overnight the back end will have sunk a bit by the morning but comes up about 15-20 seconds after starting.

-When I put the car on its highest setting the front rises quickly but the back end takes a lot more time and doesnt seem to rise as high as the front...the regulator ticks every other second in this setting, but about once a minute on normal

-Tyre pressures are normal although they are bargain tyres with about 3mm of tread left

-If I sit in the boot with the engine off, the car wont return to normal unless I jump out

I will bleed the system for air this week by doing some serious citerobics, anything else it might be? Im aware accumulator may be duff but cant afford to get it replaced anytime soon.

[MikeT]

It does point to the accumulator sphere by my reckoning though I'm an air head, not an egghead, so best get a second opinion.

[CitroJim]

We used to have eggheads here but there was an unfortunate incident involving a wall...

Now then, this statement here is the clincher:

-If I sit in the boot with the engine off, the car wont return to normal unless I jump out.

Question is, does the sit in the boot test work normally with the engine running?

Makes me think there is a bit of stiffness in the rear height corrector and it takes very little for a bit of stiffness to really interfere with ride quality. Both Height Correctors must be working absolutely perfectly for best ride quality and the ride heights must be correct too.

You need to work on getting the "sit in the boot test" to work shortly after the engine is switched off. Until this test passes, things will never be right on teh ride front.

Was the anti-sink sphere changed? I ask as although it has nothing whatever to do with sinking (it's a rear brake accumulator) I'm of the opinion that it has a small but discernible effect on ride quality if it is flat.

Finally, it is easy to get used to Citroen ride quality and it can seem to have deteriorated. To prove this, go for a ride in any average tin-sprung car and then get back int he Xantia. The mind is a funny old thing....

[seany87]

We used to have eggheads here but there was an unfortunate incident involving a wall...

Now then, this statement here is the clincher:

-If I sit in the boot with the engine off, the car wont return to normal unless I jump out.

Question is, does the sit in the boot test work normally with the engine running?

Makes me think there is a bit of stiffness in the rear height corrector and it takes very little for a bit of stiffness to really interfere with ride quality. Both Height Correctors must be working absolutely perfectly for best ride quality and the ride heights must be correct too.

You need to work on getting the "sit in the boot test" to work shortly after the engine is switched off. Until this test passes, things will never be right on teh ride front.

Was the anti-sink sphere changed? I ask as although it has nothing whatever to do with sinking (it's a rear brake accumulator) I'm of the opinion that it has a small but discernible effect on ride quality if it is flat.

Finally, it is easy to get used to Citroen ride quality and it can seem to have deteriorated. To prove this, go for a ride in any average tin-sprung car and then get back int he Xantia. The mind is a funny old thing....

All is fine when the engine is running. Slight dip as I sit in boot, then it corrects itself within 15 seconds. Not sure if anti sink was done, most probably not as the previous owner had the car as a workhorse. Im just mystified as to how the suspension could have deteriorated so badly, so quickly. First thing that came to mind was my novice mechanic skills!

Where are the rear height correctors Jim, and how can I unstiffen them?

[CitroJim]

I'm in agreement with MikeT. If you're not sure if the main accumulator was done, change it anyway. The failure of the "sit in the boot test" does often point to a flat accumulator.

One thing for sure, it's not a result of your spanner.

Where are the rear height correctors Jim, and how can I unstiffen them?

Look under the rear and towrd the middle and the HC will be plain to see. It looks like this:



Here's a working diagram of them:



Spray the area where you see the big springs on the height corrector mechanism with WD-40 and then spray them with some good quality spray grease. A bit of up and down will soon work the grease/WD mix in and free any residual stiffness.

Please support the car very securely on ramps or axle stands before going underneath to play height correctors. The suspension could suddenly collapse and if the car is not adequately supported it could crush and kill you. A golden rule when doing any work on a hydraulic Citroen is to adequately support it even if the work does not involve the suspension. Ignore at your peril.

[MikeT]

.....though I'm an air head, not an egghead,....

I'm in agreement with MikeT

Rub it in, mate, go on

[CitroJim]

.....though I'm an air head, not an egghead,....

I'm in agreement with MikeT

Rub it in, mate, go on

Oh dear Mike. I never made the connection, honestly...

[tonupteabag]

I'm in agreement with MikeT. If you're not sure if the main accumulator was done, change it anyway. The failure of the "sit in the boot test" does often point to a flat accumulator.

One thing for sure, it's not a result of your spanner.

Where are the rear height correctors Jim, and how can I unstiffen them?

Look under the rear and towrd the middle and the HC will be plain to see. It looks like this:


can i ask what the sphere is for located to the right of the height corrector as all my suspension spheres have been changed but i haven't changed the accumalator sphere at the front as it seems in good order ie i get a tick every about every 55 seconds and i haven't changed the centre rear as i wasn't sure how to test it on the car to see if its working ok:oops:

Here's a working diagram of them:



Spray the area where you see the big springs on the height corrector mechanism with WD-40 and then spray them with some good quality spray grease. A bit of up and down will soon work the grease/WD mix in and free any residual stiffness.

Please support the car very securely on ramps or axle stands before going underneath to play height correctors. The suspension could suddenly collapse and if the car is not adequately supported it could crush and kill you. A golden rule when doing any work on a hydraulic Citroen is to adequately support it even if the work does not involve the suspension. Ignore at your peril.

[jonathan_dyane]

can i ask what the sphere is for located to the right of the height corrector as all my suspension spheres have been changed but i haven't changed the accumalator sphere at the front as it seems in good order ie i get a tick every about every 55 seconds and i haven't changed the centre rear as i wasn't sure how to test it on the car to see if its working ok:oops:

That's another accumulator sphere, responsible for maintaining a pressure reserve for the back brakes, and often misleadingly called the anti-sink sphere. As far as I know there is no way of easily testing it on the car, but if it looks as if it's been there for eons it's worth replacing.

Aside from ensuring the pump isn't getting overloaded the main function of the two accumulators is to provide a reserve of braking power in case of a thrown auxiliary belt or other failure at speed. With flat accumulators on a car with anti sink you lose the brakes pretty much as soon as the engine stops.

[CitroJim]

Note that the puicture of the height corrector I posted is in fact, on close inspection, upside down.

As far as I know there is no way of easily testing it on the car, but if it looks as if it's been there for eons it's worth replacing.

No, I theorise that the anti-sink sphere could be tested by attempting to bleed the rear brakes just after the engine has stopped. I've not yet put the theory to the test...

For the cost, as you say Johnathan, you're just as well replacing it.

[citronut]

seany87 wrote,
"Need Xantia Eggheads Help"

is that hard boiled or scrambled,

i have the latter,

Jim wrote
"Note that the puicture of the height corrector I posted is in fact, on close inspection, upside down. "

what even if you are laying on your back slid under the car Jim TEA HE

regards malcolm

[tonupteabag]

thanks guys i was curious as it looks like its been on a while well maybe since noah figured out it wasn't raining anymore i'll look into a price for the rear accumalator sphere any specific tricks to getting it off????

[DHallworth]

Our HDi is much the same as this so I'm going to get it up on the ramp and lubricate both of the height correctors tomorrow.

Once these have been done I'm going to change the rest of the spheres.

I did the rear 2 when I got it as it was pitching from minimum to maximum height when we got it. I then did the accumulator to stop the pump ticking.

How many sphere's are on it? I've got 8 in my head but am unsure on these newer cars.

Front Corners (2)
Front Centre (1)
Rear Corners (2)
Rear Centre (1)
Accumulator (1)
Anti Sink (1)

David.

[CitroJim]

Yep, eight on an Exclusive David.

You're spot-on in both count and function...

[jonathan_dyane]

thanks guys i was curious as it looks like its been on a while well maybe since noah figured out it wasn't raining anymore i'll look into a price for the rear accumalator sphere any specific tricks to getting it off????

It differs from the other spheres in that it screws into a retaining bracket rather than a hydraulic unit, and has a hydraulic pipe fitted to the business end; the first time I did one I unscrewed it as if it were a 'normal' sphere and wrecked the pipe! That's certainly something to be aware of, and it's worth investing in a 8mm brake pipe spanner as a normal open ender will likely round the flare nut.