After de-pressurising the system and upon removal of rear spheres(nearside and offside wheel) there was evidently still pressure in the system painting myself and the car green!! I'm guessing that it may have been a 'ruptured' sphere somewhere..but could have been a faulty rear valve retaining pressure in the rear circuit..anyone know?
FYDAMF
LHM everywhere during sphere change
Moderator: RichardW
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tomsheppard
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If you were depressurised, there may be some LHM left in the units, but certainly not enough to spray everywhere.
Brings back memories of my first change of the fronts, LHM went everywhere, peppered the underside of the bonnet, and gave a passing bus a quick spray as well <img src=icon_smile_big.gif border=0 align=middle>
Would an anti-sink rupture have the same effect ?
I'm just thinking, it may be worth replacing the anti-sink as well ( if fitted ).
Mat.
Brings back memories of my first change of the fronts, LHM went everywhere, peppered the underside of the bonnet, and gave a passing bus a quick spray as well <img src=icon_smile_big.gif border=0 align=middle>
Would an anti-sink rupture have the same effect ?
I'm just thinking, it may be worth replacing the anti-sink as well ( if fitted ).
Mat.
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Dave Burns
- Posts: 1915
- Joined: 14 May 2001, 05:30
- Location: United Kingdom
- My Cars:
- x 2
JohnD is on the right track here, on car's fitted with antisink it is important to allow the engine to tick over not only during lowering of the suspension but also for a minute after the body has reached its lowest point and before releasing the pressure at the regulator.
If you simply stop the engine as soon as the body is down, the antisink valves can close well before the sphere's have had time to discharge the LHM stored in them, and if not allready closed, they will close the moment the pressure release screw is opened, resulting in any trapped pressure in the suspension sphere's remaining so.
The sphere's are still at full operating pressure as the car is being lowered, only when the oil has been evacuated from the suspension cylinder's and strutts, and the body sits down on the stops do the sphere's then begin to empty.
Sphere's that have very little gas pressure left in them will take much longer to discharge than healthy ones, this is because the small bore of the hydraulic pipes resists the flow of oil along them much more at low pressure than at the high working pressure of the system, so a good sphere at high pressure will force oil along the pipes at a much higher rate, and empty sooner.
Thus if the front or rear suspension was just about solid, I'd increase the waiting time at tickover to two minutes just in case.
Those of you who enjoy the oil shower should disregard the above, I wouldn't want to deprive you of your fun<img src=icon_smile_big.gif border=0 align=middle><img src=icon_smile_tongue.gif border=0 align=middle>
Dave
If you simply stop the engine as soon as the body is down, the antisink valves can close well before the sphere's have had time to discharge the LHM stored in them, and if not allready closed, they will close the moment the pressure release screw is opened, resulting in any trapped pressure in the suspension sphere's remaining so.
The sphere's are still at full operating pressure as the car is being lowered, only when the oil has been evacuated from the suspension cylinder's and strutts, and the body sits down on the stops do the sphere's then begin to empty.
Sphere's that have very little gas pressure left in them will take much longer to discharge than healthy ones, this is because the small bore of the hydraulic pipes resists the flow of oil along them much more at low pressure than at the high working pressure of the system, so a good sphere at high pressure will force oil along the pipes at a much higher rate, and empty sooner.
Thus if the front or rear suspension was just about solid, I'd increase the waiting time at tickover to two minutes just in case.
Those of you who enjoy the oil shower should disregard the above, I wouldn't want to deprive you of your fun<img src=icon_smile_big.gif border=0 align=middle><img src=icon_smile_tongue.gif border=0 align=middle>
Dave
Thanks guys,
Could be you're right Dave as I simply lowered the car, left it for around 10 secs and turned off and then de-pressurised so I guess it was residual pressure.
With regard to anti sink, I replaced that too along the centre and both wheel spheres. The ride is certainly improved (more controlled/smooth body roll for one) but still harsher than expected.
There was a problem (with the old spheres)with the rear dropping like a stone a few seconds - few minutes after start-up (this was not due to the 'keeping the brakes on not letting suspension drop' scenario often experienced at traffic lights.. Pretty sure the problem is still there but its alot less noticeable. I also feel little difference between comfort and sport setting (although there is some) Could this be a control valve (or something else??) problem or are xantia H2s just harder than a BX (what I'm used to)
FYDAMF
Could be you're right Dave as I simply lowered the car, left it for around 10 secs and turned off and then de-pressurised so I guess it was residual pressure.
With regard to anti sink, I replaced that too along the centre and both wheel spheres. The ride is certainly improved (more controlled/smooth body roll for one) but still harsher than expected.
There was a problem (with the old spheres)with the rear dropping like a stone a few seconds - few minutes after start-up (this was not due to the 'keeping the brakes on not letting suspension drop' scenario often experienced at traffic lights.. Pretty sure the problem is still there but its alot less noticeable. I also feel little difference between comfort and sport setting (although there is some) Could this be a control valve (or something else??) problem or are xantia H2s just harder than a BX (what I'm used to)
FYDAMF