Adjusting ride height on normal suspension setting

BX Tech talk
Jugostran
New Member
Posts: 17
Joined: Fri Sep 10, 2021 6:22 pm
Location: Subotica
My Cars: 1989 Cimos-Citroën BX 16 TRS

Adjusting ride height on normal suspension setting

Post by Jugostran »

Hey there,
I have been reading through some old threads regarding this topic, and found out that my BX rides a bit too high on its normal suspension setting. I did the "four finger test" (gap between tire and wheel arch), and concluded that it rides 3-5 cm too high. The rear also raises slightly after coming to a stop, and the front drops about 3-5 cm immediately after shutting it off. Now, I have seen some discussion regarding what the best way is to adjust the suspension, but I haven't managed to track down any mention of what exactly needs to be adjusted in order to change ride height. If anyone knows, I'd greatly appreciate it!
Cheers!

User avatar
Fumbler
BXpert
Posts: 211
Joined: Thu May 20, 2021 7:21 pm
Location: Tunbridge Wells
My Cars: Citroen BX14 RE
Nissan Micra Shape
x 24

Re: Adjusting ride height on normal suspension setting

Post by Fumbler »

The rear raising when coming to a stop is completely normal. When braking, all hydraulic effort is directed to the brakes, so pressure will release in the suspension.
The height correctors operate via a linkage which connects to the anti-roll bars. To adjust, get the car on a 4-post lift, never on the ground slacken the bolt on the linkage clamp just enough so the clamp moves with the tap of the hammer. When you move the clamp, the linkages will move, and the front will rise or fall depending on the direction it turns.
This is a bit of a general overview as I recently went and had a specialist adjust the height and allowed me to see how it worked. I mightn't be completely correct.

User avatar
Jaba
1K Away
Posts: 1747
Joined: Tue Jul 05, 2005 7:54 am
Location: Usually in the garage
My Cars: BX GTi, C3 Auto
x 43

Re: Adjusting ride height on normal suspension setting

Post by Jaba »

I learnt how to adjust the height linkages from Haynes so if you don't have a copy this would be a good acquisition to help you understand the process. I never measure the actual height in mms as the 4 finger test is good enough and adjust the rear end after the front and get the sills parallel to the ground. Its important to have the correct linkage gaps for the HC operating arm at the front and rear.

Its not difficult to do but be prepared to do it safely and to not get it right the first few attempts.
The Joy of BX with just one Citroën BX to my name now. Will I sing Bye Bye to my GTI or will it be Till death us do part.

User avatar
white exec
BXpert
Posts: 601
Joined: Sat Sep 12, 2020 4:04 pm
Location: Sayalonga, Malaga
My Cars: 1992 BX19D Millesime
- LHD, NA, AC, RP_5800
1996 XM 2.5TD Exclusive
x 61

Re: Adjusting ride height on normal suspension setting

Post by white exec »

Rear raising when braking is normally a sign that there is air trapped in the rear suspension/brakes. This readily compresses when the brakes are applied, but expands again when the brakes are eased off, which can cause the rear end to rise.

Excessively fierce rear brakes (rare on hydraulic Citroens, with their small rear discs and pads) would cause the rear end to squat when brakes were applied.
One of the great things about our fluid suspension is that the car is designed to ride level under all normal conditions.
An emergency stop might cause a small amount of front end dive, but this should be minimal.
Chris

Kaapelimies
BXpert
Posts: 276
Joined: Wed Feb 10, 2010 9:01 am
Location: Hollola, Finland
x 16

Re: Adjusting ride height on normal suspension setting

Post by Kaapelimies »

white exec wrote:
Tue Nov 09, 2021 7:50 am
Rear raising when braking is normally a sign that there is air trapped in the rear suspension/brakes. This readily compresses when the brakes are applied, but expands again when the brakes are eased off, which can cause the rear end to rise.
Yes. And to get rid of this, bleed the rear brakes. Engine running, rear wheels on ground, install brake assistant (here we have snow brush or small shovel, to push the brake pedal) and loose a little the nipple in the saddle. There will be a lot of pressure and air bubbles so hold a rag over it not to make a mess. If you don't have alloys of teenage-driver model, then this trick won't work as you need to remove the wheel to get access :lol: .
BX 4x4 estate, several BX Van's and some more normal estates in Finland.

User avatar
white exec
BXpert
Posts: 601
Joined: Sat Sep 12, 2020 4:04 pm
Location: Sayalonga, Malaga
My Cars: 1992 BX19D Millesime
- LHD, NA, AC, RP_5800
1996 XM 2.5TD Exclusive
x 61

Re: Adjusting ride height on normal suspension setting

Post by white exec »

This is the official way to bleed the braking system...
.
Brake bleeding - BX, XM.JPG
Source: Citroen 'Private Cars' booklet, 1992 CAR050920 p.202 (AX, ZX, BX, XM)
Chris

Defender110
Over 2k
Posts: 5917
Joined: Wed Dec 16, 2009 8:02 pm
Location: Harwood, Bolton
My Cars: Land Rover Discovery Series 1 200tdi 3 door
Land Rover Discovery Series 2 Facelift TD5
2020 Fiat Panda cross 4x4 twin air.
x 26

Re: Adjusting ride height on normal suspension setting

Post by Defender110 »

white exec wrote:
Tue Nov 09, 2021 7:50 am
Rear raising when braking is normally a sign that there is air trapped in the rear suspension/brakes.
It's often gas in the system on a BX from leaking spheres too, certainly not normal behaviour and should be cured like you said by bleeding the brakes and replacing spheres if required.
Kevan
1997 Mercedes C230 W202
2003 Land Rover Discovery Series 2 Facelift TD5 - Daily driver / hobby days and camping.
1993 Land Rover Discovery 200tdi Series 1 3 door - in need of TLC
2020 Fiat Panda 4x4 Cross Twin Air.

Jugostran
New Member
Posts: 17
Joined: Fri Sep 10, 2021 6:22 pm
Location: Subotica
My Cars: 1989 Cimos-Citroën BX 16 TRS

Re: Adjusting ride height on normal suspension setting

Post by Jugostran »

Thank you all for the excellent advice!
I will probably take my car to a specialist (provided I track one down) as there are lots of issues to adress in addition to the incorrect ride height (leaking pressure regulator, squeaky brakes and a leaky LHM reservoir).
Last edited by Jugostran on Thu Nov 11, 2021 7:11 pm, edited 1 time in total.

Jugostran
New Member
Posts: 17
Joined: Fri Sep 10, 2021 6:22 pm
Location: Subotica
My Cars: 1989 Cimos-Citroën BX 16 TRS

Re: Adjusting ride height on normal suspension setting

Post by Jugostran »

Kaapelimies wrote:
Tue Nov 09, 2021 2:47 pm
white exec wrote:
Tue Nov 09, 2021 7:50 am
Rear raising when braking is normally a sign that there is air trapped in the rear suspension/brakes. This readily compresses when the brakes are applied, but expands again when the brakes are eased off, which can cause the rear end to rise.
Yes. And to get rid of this, bleed the rear brakes. Engine running, rear wheels on ground, install brake assistant (here we have snow brush or small shovel, to push the brake pedal) and loose a little the nipple in the saddle. There will be a lot of pressure and air bubbles so hold a rag over it not to make a mess. If you don't have alloys of teenage-driver model, then this trick won't work as you need to remove the wheel to get access :lol: .
I have 1989 architect-spec that has standard hubcaps with steelies (though the hubcaps have long since biodegraded and liberated themselves from the car), so accessing the brakes is quite a chore.

User avatar
white exec
BXpert
Posts: 601
Joined: Sat Sep 12, 2020 4:04 pm
Location: Sayalonga, Malaga
My Cars: 1992 BX19D Millesime
- LHD, NA, AC, RP_5800
1996 XM 2.5TD Exclusive
x 61

Re: Adjusting ride height on normal suspension setting

Post by white exec »

Put car on highest, jack up a tad further and support, remove wheels, and bleed as described.
Chris

User avatar
Jaba
1K Away
Posts: 1747
Joined: Tue Jul 05, 2005 7:54 am
Location: Usually in the garage
My Cars: BX GTi, C3 Auto
x 43

Re: Adjusting ride height on normal suspension setting

Post by Jaba »

Leaking LHM reservoir: is this from the underneath if so it will have rusted through. The rust holes can be repaired with ingenuity but sourcing a replacement is easier.
The Joy of BX with just one Citroën BX to my name now. Will I sing Bye Bye to my GTI or will it be Till death us do part.