Suspension Maintenance

[puffthemagicdragon]

This is very much a novice question so apologies in advance!

From the various posts I gather that suspension and accumulator spheres should be changed / re-charged on a regular basis. There doesn't seem to be any mention of this in Haynes as a maintence item, so I'm wondering how one is supposed to deduce that this needs doing? Also should they all be changed as a set?

My VSX is now approaching 110K miles and is still on original spheres (well at least I haven't touched them since acquisition at 48K). She is also losing fluid on a regular basis, but not so you can see, it just goes down about 1/2 litre a week.

Some insight into these mysteries would be very helpful please.

[DerekW]

Regular sphere changes are not necessary. Some spheres do lose gas pressure slowly over a long period of running (for the multilayer diaphragm spheres, a very long period) but the normal sympton that indicates a suspension sphere change is due is a marked deterioration in ride quality.

If that occurs, it's not always necessary to change all the spheres. It's always worth while just changing the two hydractive spheres first as they have the most pronounced effect on ride comfort.

The sign that the accumulator needs changing is frequent clicking of the pressure release valve. If the time interval between clicks is less than 20 - 30 seconds then its time to change the accumulator. This, as you probably know, is a device to store hydraulic fluid under pressure; it acts as a reserve to operate steering and front brakes and also damps out the pressure pulses from the pump.

If your car has anti sink fitted, there's also a so-called anti sink sphere fitted. This is fitted in the most inaccessible place imaginable and has no effect on the anti sink system itself, its only purpose in life is to provide a supply of pressure to the rear brakes in the event of total hydraulic failure. Unless you're a perfectionist, or a masochist, it's best left alone.

Derek

[jorgy9]

re. the HLM loss, you just reminded me that mine was loosing at that pace when I bought it, and I could not see where from. An hydraflushing course fixed this -so I have to assume that badly blocked points somewhere pushed the liquid outwards from unions/seals-.

G

[puffthemagicdragon]

Many thanks for the guidance guys, I now feel better knowing I've not been hopelessly neglectful.

Looks like some hydractive spheres need to go on the shopping list though

[bigjohnh]

I know a couple of old boys near me (South East London) who remove the spheres, check the pressure and recharge if necessary. They charge 15 quid a sphere but ONLY if recharge is needed. That's a bargain.

John

[DerekW]

At least sphere changes are easier to do than spring changes on a Capri!

Derek