Why differant spheres?

This is the Forum for all your Citroen Technical Questions, Problems or Advice.

Moderator: RichardW

Post Reply
RStacey
Posts: 35
Joined: 04 Mar 2005, 22:37
Location: Kent
My Cars:

Why differant spheres?

Post by RStacey »

Hi

Does anybody know why the front sphere specification for a 1.9D xantia is different from the TD? I have just "borrowed" the spheres from my daughters off the road 1.9TD and put them on my 1.9D until I can buy some new spheres - I was going to buy the correct spheres for the 1.9D, but the ride with the TD spheres appears fine and I am now unsure what to buy
Any thoughts welcomed

Richard

ps - thanks for a superb forum - If I have a Xantia problem I always look here first
1999 Xantia HDi Exclusive
2003 C5 HDi SX
1995 Xantia 1.9TD
1994 Xantia 1.9D
User avatar
AndersDK
Posts: 6060
Joined: 21 Feb 2003, 04:56
Location: Denmark
My Cars:
x 1

Post by AndersDK »

Supposed to be different i.e. harder damped for the faster TD model.

Be careful ! If you have been driving around for longish with flat spheres - anything replacing these may feel like a new life to your Xantia :wink:
Anders (DK) - '90 BX16Image
User avatar
Mandrake
Posts: 8615
Joined: 10 Apr 2005, 17:23
Location: North Lanarkshire, UK
My Cars:
x 664

Post by Mandrake »

Yes,

The early (before 1996) 1.9D spheres give a softer ride because they have higher gas pressure and larger damper holes.

What happened was that in the early models of Xantia they started out with the lower powered models having softer ride, however the higher powered models (including 1.9TD) had a firmer ride and damping to handle the higher power and therefore higher likely dynamic forces on the car. (The softer springing of the 1.9D was just too soft for anything but leisurely driving, and didn't give very good handling)

From 1996 onwards all the models (except Activa) were standardised into using the same spheres with only the following variations: Hydractive2 vs non-Hydractive2, and for the rear spheres also Estate vs Hatchback.

So there are four versions of rear spheres and two versions of front spheres, that cover all models, post 1996, not counting the different diaphram materials.

This means that since 1996 the 1.9D and 1.9TD both get the same spheres anyway, which are equal in pressure to the old 1.9TD spheres.

So in summary - you can put 1.9TD spheres on a 1.9D with no problems - you will get a slightly firmer ride than original with better handling. The ride will be the same as a 1.9TD.

You should not put 1.9D spheres on a 1.9TD - you will get the soft ride of the 1.9D but you will also get the poorer handling, and together with the extra horsepower its not a good combination.

Regards,
Simon
Simon

1997 Xantia S1 3.0 V6 Auto Exclusive in Silex Grey
2016 Nissan Leaf Tekna 30kWh in White

2011 Peugeot Ion Full Electric in Silver
1977 G Special 1129cc LHD
1978 CX 2400
1997 Xantia S1 2.0i Auto VSX
1998 Xantia S2 3.0 V6 Auto Exclusive
RStacey
Posts: 35
Joined: 04 Mar 2005, 22:37
Location: Kent
My Cars:

Post by RStacey »

Thanks - that explains it perfectly - I've no idea what the original spheres felt like as the front spheres were deflated when I bought the car but I dont need it any softer so I'll stick with the TD spheres
1999 Xantia HDi Exclusive
2003 C5 HDi SX
1995 Xantia 1.9TD
1994 Xantia 1.9D
User avatar
Mandrake
Posts: 8615
Joined: 10 Apr 2005, 17:23
Location: North Lanarkshire, UK
My Cars:
x 664

Post by Mandrake »

RStacey wrote:Thanks - that explains it perfectly - I've no idea what the original spheres felt like as the front spheres were deflated when I bought the car but I dont need it any softer so I'll stick with the TD spheres
Probably because they were almost "deflated" :)

The gas slowly leaks out of spheres over a period of years and the more that leaks out the stiffer the suspension gets, until finally its completely rigid. It's only because they ride so soft in the first place that people don't notice until they're nearly stuffed...

Regards,
Simon
Simon

1997 Xantia S1 3.0 V6 Auto Exclusive in Silex Grey
2016 Nissan Leaf Tekna 30kWh in White

2011 Peugeot Ion Full Electric in Silver
1977 G Special 1129cc LHD
1978 CX 2400
1997 Xantia S1 2.0i Auto VSX
1998 Xantia S2 3.0 V6 Auto Exclusive
Post Reply