Saggy Xantia back end?

XantiaMan · Unread post by **XantiaMan** » 18 Aug 2007, 13:12

I have a 1997 Xantia 1.9 TD LX, its a lovely car, and seems to ride very well, and handle as you would expect a Xantia would. However, i need to know if its suspension behaviour is normal.

When you turn the engine off, and get out the car, the car rises at the back (reduced weight) then drops back down, lower than i would expect.

With the engine running if you put your weight on the back, it will respond to this in a few seconds and rise up to compensate.

As i understand it, my car has an anti-sink which should stop it sinking with the engine off, but it always looks too low to me?

When started from cold it takes about 5 seconds for the stop lights to go out, when started during the day, less time.

Any ideas? Below is a picture with engine off.

Gareth

reblack68 · Unread post by **reblack68** » 18 Aug 2007, 13:31

It sounds about normal to me. With a good accumulator sphere it should rise up when you sit in the back even with the engine off.

When the anti-sink sphere is flat the car doesn't sink when you park it, it sinks when you start the engine again.

Xaccers · Unread post by **Xaccers** » 18 Aug 2007, 14:03

I have a similar situation with my 2.1TD, I turn the engine off, get out, it pops up then sinks way down.
Suspension is firm like a normally sprung car, but not flat sphere firm, and all spheres were changed back in April.
My 1.9TD on the other hand stays up when I get out, has a much softer ride too.

XantiaMan · Unread post by **XantiaMan** » 18 Aug 2007, 15:07

Ok thats good if its considered to be acceptable behaviour! some of the spheres have been replaced over the years, the linkages that go onto the anti roll bars are not seized and intact too. What is considered a good life span for spheres on a normally driven (i.e up and down the motorway every day and shopping trips) Xantia?

Overall i am very impressed with the car, it does take a while to start from hot sometimes but is very quick to start from cold. It's also a lot better since i tweaked the fuel pump fuelling, some extra smoke but far more responsive and torquey mid range.

Gareth

deian · Unread post by **deian** » 18 Aug 2007, 16:06

reblack68 wrote:When the anti-sink sphere is flat the car doesn't sink when you park it, it sinks when you start the engine again.

Reallly? So why does it sink down in the first place? I thought if the anti-sink is there to stop it sinking when parked, so as not to be like the older citroens... that sink overnight?

If it sinks when parked, what does this indicate? I have the same problem on my V6 and I have suspected the anti-sink sphere. Now you have confused me.

XantiaMan · Unread post by **XantiaMan** » 18 Aug 2007, 16:17

I just went out and measured the the heights roughly, 400mm when engine off at the rear, 430mm with engine running but unladen, at the front it was 170m with the engine running (taken from the base of the subframe) I think that sounds about right.

Xaccers · Unread post by **Xaccers** » 18 Aug 2007, 18:08

deian wrote:
reblack68 wrote:When the anti-sink sphere is flat the car doesn't sink when you park it, it sinks when you start the engine again.
Reallly? So why does it sink down in the first place? I thought if the anti-sink is there to stop it sinking when parked, so as not to be like the older citroens... that sink overnight?

If it sinks when parked, what does this indicate? I have the same problem on my V6 and I have suspected the anti-sink sphere. Now you have confused me.

That's what I used to think, but people "in the know" here said that the acc sphere keeps the car up when the engine is off, and the A/S just covers the drop in pressure when the engine starts before it re-instates the pressure after a few hundred revolutions of the pump.

mezuk04a · Unread post by **mezuk04a** » 18 Aug 2007, 19:09

I think the back end looks about right to be fair, if you havent got any really issues with the suspension I would just leave it as it is.

reblack68 · Unread post by **reblack68** » 18 Aug 2007, 19:21

I think it's a non return valve that keeps the back end up. When you start again the valve opens and the back would sink if there wasn't stored pressure in the anti-sink sphere.

A Xantia should rise when you get out and then sink back down to compensate. They do seem to sit a little lower when parked than when they are running.

mpr1956 · Unread post by **mpr1956** » 19 Aug 2007, 10:35

Hi Gareth.. the poor hot starting on my 93tdsx was greatly improved by replacing the injector leak-off pipes.. A fiver and ten minutes well spent ! Nice finish on your car btw... regards, Martin

XantiaMan · Unread post by **XantiaMan** » 19 Aug 2007, 12:48

mpr1956 wrote:Hi Gareth.. the poor hot starting on my 93tdsx was greatly improved by replacing the injector leak-off pipes.. A fiver and ten minutes well spent ! Nice finish on your car btw... regards, Martin

Thanks Martin. I've not seen any leaks when looking but for the sake of a couple of quid and an hours fiddling about i will replace them as i've read elsewhere on this forum that its a known problem.

The car cost me £600 quid, it's been well looked after with oil change every 6k and all servicing done by a specialist. I spent a morning mopping it then waxed it and it came out fantastic. Although its had some paint over the years, the original Citroen paint is far better than that of Vauxhall and Ford at the time. I parked next to a C5 yesterday and noted it was better than that of some BMW's at work! No rust cosmetically and mint underneath!

I have tweaked the fuelling slightly too, on previous cars with the same pump i did identical adjustments, simply took the top off the pump, remove plunger and diaphragm, noted the position of the dimple which was at 2 o clock and move this to 3 o clock, this not only gives a bit more fuel but compensates for wear on the metering pin as you always see a groove, i also turned the cog 1/4 turn clockwise and then to complete, half a turn clockwise on the boost compensator screw. It now pulls well from 1500rpm and very strong from 2k to just past 4k, i'm more than happy as it doesnt lard arse around now and mpg is unaffected.

Gareth

XantiaMan · Unread post by **XantiaMan** » 19 Aug 2007, 13:04

Here are some more pictures.

Xaccers · Unread post by **Xaccers** » 19 Aug 2007, 20:28

Try running it on vegetable oil.

Mandrake · Unread post by **Mandrake** » 19 Aug 2007, 20:53

XantiaMan583 wrote:Here are some more pictures.

Rear height looks perfectly ok to me, especially in that last picture - its normal for the guard to be about in line with the top of the tyre at the rear.

When you get out of the car the rear will rise a long way due to the weight change and the fact that the rear suspension is (supposed to be) so soft.

If you watch it correct downwards after you get out it will seem like its going an awful long way, but thats normal...

If you're really paranoid about it and want to do an accurate measurement, have a look at:

http://homepages.igrin.co.nz/simon/imag ... ia_height/

If the rear height corrector linkage is a bit rusted/seized, it may cause the height correction to overshoot or undershoot - measure the height after both an upwards and a downwards correction and compare them - ideally they should be within about 10mm of each other. If there is a large difference of say 30mm I'd give the linkage a good spray and grease to try and free it up a bit.

By the way the calculated rear height for mine to the subframe with my 205/60/R15 tyres works out to about 436mm, so 430 doesn't sound too far wrong.

If the ride and handling seems fine and it achieves the same height fairly accurately each time, I would leave the height alone.

Regards,
Simon