Strut Near To Failure?, Change strut top.

[Robin]

Can I share a picture or two with you all and seek an opinion please? The pictures are of the O/S and N/S strut tops. The offside strut top is rusting under the rubber and the nearside is apparently sound still. No obvious difference in the relationship of the top assembly to the bodywork which is clean and sound throughout.

Does this look normal to you or should I be considering the replacement of the top assembly sooner rather than later?

It's on a 97 2.5TD estate.

Many thanks, Robin.

This post has been edited by Robin on January 28, 2007 04:03 pm

[techmanagain]

Lookingat the picture and taking into account the age of the car. I would suggest that you drop the leg unit out of the top mount, remove the mount and wire-brush/ derust and paint it with Hammerite or similar and put it back for another 50K miles or so. Basically I would say it's still very sound (from what I can see from the photo).

[Robin]

Cheers Techman. It is similar to the N/S one in that the distance from the body work to the top of the strut is the same and this one is rust free.

The car gets a major spring overhaul in a few months so I will have a got at them then.
Robin

[Andmcit]

The picture link doesn't open for me, but bear in mind, the rubber can fail too:



In fact, if the rubber is a bit flaky on the underside of a Xantia this actually
causes the main problem as water/moisture is trapped against the rather
thin metalwork which fails quite spectacularly. Loads of Xantiae are failing
at the moment now they've reached critical mass...

I'd get the car on high and without getting into the gap between the wheel
and the top of the wheelarch check behind the bellows - look out for any
sign that there's rubber cracking and any rust on ther donut metal mounting
plate that is bolted against the wheelarch.



NOTE, the metalwork on this one of a 1990 2.0SEi that popped the bonnet
isn't rusty!!

Andrew

This post has been edited by Andmcit on January 28, 2007 06:11 pm

[noz]

Hi Robin,

I don't think your struts look any worse than any of ours. The flaking rust and disintegrating rubber looks alarming but I'm not sure how much that contributes to the structural strength of the strut top.

I've attached a document whih I hope will permit some kind of objective assessment of strut tops. I have made some measurements on my own car and invite everyone ot carry out the same measurement on theirs. Maybe if we see a picture of strut top condition overall we can then make an assessment of what constitutes a good top and a bad top.

Sorry for hijacking your thread but maybe the answer to your question lies in the answers to this poll.

Cheers

noz

[Andmcit]

One, admittedly basic, rule of thumb that may help is the gap between the sphere and the
lip of the scuttle trim that you can see the first picture posted (yes - it did open for me in a
different browser, though the new pdf file doesn't).

Andrew

This post has been edited by Andmcit on January 28, 2007 06:46 pm

[Robin]

Why do I get a load of gobbledygook when I try to open the attachements? I cannot even open the one I posted
Robin

[noz]

Hi Robin,

Right click on the file and save it to your hard drive before opening. I'm not sure where the bug is.

Cheers

noz

[xmexclusive]

Hi All

If it was my car I would be willing to do the same as Techmanagain suggests.

The two types of failure are different and the only common feature is the final mode of strut failure.

If the front suspension is run for a long period failed (in very hard mode) it is possible to shear the rubber block that forms the strut head so that it pops up through the centre of the steel cone. This type of shear failure of the rubber block is fairly slow and a good number have been spotted in the early stages by an examintion of the underside of the strut head.

In an XM the steel cone has a very thin layer of non structural rubber moulded on to its top. It seems to me that in Robins photo it is this thin top rubber layer that has part failed exposing rust underneath. This type of rubber failure and cone rusting is common in UK XM's. I think the rubber bond to the top of the steel fails quite quickly and it the sucks in water probably by capillary action. Once the rusting is well established it eventually removes structural strength from the steel cone and effectively enlarges the size of the hole in the cone increasing the shear on the rubber block and making it easier for the rubber block to force its way through.

This latter type of failure is typically a sudden shear failure of the rubber block in the suspension mount. If I fit new strut heads I am thinking seriously of removing the top covering of rubber from them and rust proofing the exposed steel cone.

Unlike the XM the Xantia has a different design of steel cone for fixing to the vehicle chassis and Citroen in their wisdom put the thin layer of protective rubber over the underside of steel cone base. It suffers the same peeling failure/water penetration/rusting problems but was fitted in the top of the wheel arch and is continuously supplied with large volumes of water, road salt and air.
As a result XM strut heads only rust slowly from the top down. Xantia strut heads may also rust in that same way from the top down but they seem to fail because once rusting starts in the strut base it is attacking the steel cone at the worst possible structural position and progresses at an alarming speed.

Regards

XMexc

[Robin]

Thanks all. First found the way to open the attachements, thanks Noz.

It does look to me as though the best way forward is a check of condition in general. first a good look around underneath and then if OK drop the struts and clean up in Spring.

I need the car daily so it is a matter of waiting until the other wheels are back on the road in Spring. The Xantia is for SWMBO or else

Robin

P.S. I guess the Xantia will need doing too. Same age same mileage!

[Andmcit]

Robin,

If I were you, I'd have a good close look at the Xantia first. The drooping bellows
if a surefire indication that all is not well as it relies on the structural stability of
the crown's diameter to clip around - it starts to deform when the rust get's in and
there's then nothing to hold the bellows on

The good news is that the R plate shouldn't be in too bad a state, but it does depend
on how fanatical the local council is in St Ives! Guess there'd be more salt air in the
Cornish one mind...

Andrew

[rg]

Some photos of my strut tops taken off, inspected, and cleaned here:-

http://www.flickr.com/groups/xm_on_flickr/

rg

[Andmcit]

These any good to you then:

http://web.telia.com/~u43116231/front%20strut.htm

Andrew

[steelcityuk]

I've added a photo of the nearly failed strut top on the XM I bought.

http://www.flickr.com/groups/xm_on_flickr/

The rubbers seem OK just the metalwork that's failed.

Steve.