Does the C5 x7 hydractive back suspension have any "bonus jobs" worth doing?

[Jay-Bruce]

We've got a long running MOT advisory on our car "slight misting o/s/r shock absorber", and as I'm going to be getting tore in about the back end rusty suspension pipework, replacing the rusty and scarce/unobtainable LDS pipework with the pattern parts I'm developing, I figured screw it, I'll get it a pair of cylinders. So, the car's back end is going to be in bits, replacing the LDS pipework, replacing the original rear firmness regulator with a 39,000km one I imported from Australia, new suspension cylinders, transferring the 5 month old spheres onto the new & nearly new hydraulic components. I was wondering is there any other known weak spots that will easier to replace while it's so thoroughly dismantled?

[Hell Razor5543]

I would be inclined to open up the suspension pump motor and give it a good clean out with brake/clutch cleaning fluid. The motor has 4 brushes, which means that carbon dust will have been generated. If any LDS gets into the motor (and, because of its' location right under the reservoir, it is almost certain some WILL have got in) it will mix with the dust, forming a carbon 'sludge' that is conductive. Eventually enough 'sludge' will build up to blow the 40A Maxi fuse. I recently have experienced this with my facelift C5, and I had to get a replacement unit from my local scrapyard (as the old motor smelled as though it was burnt out).

[GiveMeABreak]

I was wondering is there any other known weak spots that will easier to replace while it's so thoroughly dismantled?

Are you going to replace the rear Centre Spheres Jay? If you are replacing the rear hydraulic block, they'll have to come off anyway, so may be a good idea to replace these as well. At least you'll have new spheres at the rear and may find the ride improved.

Just bear in mind the centre spheres have different pressures for both the front and rear centres and are also different from the corner spheres.

The rear struts are still available. Shout if you need parts.

[Jay-Bruce]

Our cherished Citroen C5 3.0HDi exclusive tourer passed it's MOT today, with 5 advisories, one on that infernal shock, for which I've finally remembered to order a pair of new rear cylinders. And an advisory on each tyre, on an x7 that has the 19" 'Adriatic' wheels. But the car is "cherished", so 4 new Michelin Pilot Sport 5s will be ordered tomorrow. I actually had my mouse pointer hovering over the confirm payment button a mere twitch of an index finger away from placing the order on a set of four PS5's earlier when I decided that rather than just going through one of the usual online behemoths, I would see if any of the local places can come close to the online price. Even if they are £20-£30 more than an online tyre place, I'd rather give my money to a local enterprise. Regardless of what the locals do on price, even at online cutthroat prices, those 4x Michelin 19s is going to be an ouchy purchase.

@Hell Razor5543 Doing the motor while the system is depressurised is a really good shout, and as an added bonus, when I take the tank off to get to the motor, that will make it a lot easier to do the LDS pipes from the BHI to the firmness regulators. So, yeah, I'll get that done en-passant.

@Givemeabreak - Picking up on HellRazors suggestion, can you point me in the direction of a dummys guide to removing the LDS tank? Coming back to your comment about the spheres, I was under the motor about 5 months ago, to do the "Phil Cruiser repair" (c6 owners club member) on our rear firmness regulator, and while I was at it, seeing as the system was depressurised, I replaced all 7 spheres. So I'm planning on transferring the 5 month old spheres onto the new cylinders and almost-new rear firmness regulator*, but if I hadn't done them recently that would have been a great idea.

It was when I was under the motor I noticed our X7's rusty LDS pipes which started the whole journey of developing my own solution. I'm actually looking forward to testing those "LDS System Compatible" fittings.

*reason I went with the ozzy regulator is that apart from it looking like new, and being low miles, it came with a full set of hoses and flexi pipes, the total prices of the hoses which were available were more than the cost of a new regulator, and I seem to remember there being some parts that weren't available.

[Hell Razor5543]

@Jay-Bruce It is not that difficult to remove the tank, but it could be messy, if you are not careful. Have a 5l can ready to catch the old LDS. Get hold of a pair of carpenters pincers, as they will help you to re-fasten the pipe clips (this is based on myglarens' suggestion, which I tried and found worked well). You will need to remove the offside wheel, so properly raise and support the car. Then lower the suspension (and, if you can, using a Lexia, depressurise the suspension system, to reduce the amount of LDS being sprayed around the engine bay once you loosen off the two high pressure pipes). Remove the inner front plastic mudguard, and you will see a pipe coming down from the engine bay into the steering pump assembly. Undo the clip at the top of the pipe (a blade screwdriver worked well for me), get the can ready, pull the pipe down and put the can in place.

There are a pair of small 'O' rings on each of the two high pressure pipes. Make sure these don't come off, or (if they do) note which way round they go and keep them safe.

It is fairly simple to do the job (I succeeded, based on the information provided in my following thread), but the most awkward bit was undoing the two nuts that hold the suspension pump in place. The bolts hold the suspension pump in place, but they also help to hold the steering pump as well. One nut is accessible, but the other (the one nearer the front of the car) is a bl00dy pain to undo and do up. A ring spanner helps (10mm, IIRC), but you will be working blind, and it is VERY easy to drop the sodding nut! On page two of my thread Marc has posted up a diagram, and you can see that two of the rubber 'mounts' slide off the bracket (the nearer to the engine), while the other two are the awkward pair.

https://www.frenchcarforum.co.uk/forum/ ... 3&start=15

Unless you plan to re-use the LDS you should also get 5l for when you get the car fully fettled.

[bobins]

Our cherished Citroen C5 3.0HDi exclusive tourer passed it's MOT today, with 5 advisories, one on that infernal shock, for which I've finally remembered to order a pair of new rear cylinders. And an advisory on each tyre, on an x7 that has the 19" 'Adriatic' wheels. But the car is "cherished", so 4 new Michelin Pilot Sport 5s will be ordered tomorrow. I actually had my mouse pointer hovering over the confirm payment button a mere twitch of an index finger away from placing the order on a set of four PS5's earlier when I decided that rather than just going through one of the usual online behemoths, I would see if any of the local places can come close to the online price. Even if they are £20-£30 more than an online tyre place, I'd rather give my money to a local enterprise. Regardless of what the locals do on price, even at online cutthroat prices, those 4x Michelin 19s is going to be an ouchy purchase.

Jay - Michelin have an offer on at the moment, check their website for details.

Michelin offer - Michelin

[GiveMeABreak]

@Givemeabreak: can you point me in the direction of a dummys guide to removing the LDS tank?

I'll put a guide together for the tank shortly and a link here after.

[Hell Razor5543]

I would also suggest you thoroughly inspect the LDS reservoir. They have been known to fail (pinhole leaks), and it could be a good idea to properly look it over when you have it off the car.

[GiveMeABreak]

Illustrated and combined guide here Jay:

C5 X7 Drain, Refill, Bleed Suspension Circuit & LDS Tank Removal

[Jay-Bruce]

Cheers for the info lads...

I got slightly lost on the tyre offer, the Michelin website's special offer page that @bobins mentioned showed me different dealers from where the Michelin PS5 webpage pointed me to, so I got in touch with Michelin promotions by giving them a call on 03003033585, and the very helpful woman I spoke to pointed me to a different Michelin page that has a different offer worth the same money:


https://car-offers.michelin.co.uk/UK/PIM4

Basically it's a case of buy the tyres, filling out a web form, uploading the receipt, and Michelins should then issue the refund. But the benefit was this new offer page meant I could price run the tyres, and buy wherever was cheapest, rather than be held ransom to the prices of the anointed dealers from the first offer. So I was able to get the four tyres for £690 fitted* and I should get £100 of that back from Michelin, meaning I'm looking at ~£590 for 4 x 245/40/19 Michelin Pilot Sport 5's fitted and balanced and the old tyres disposed of. I've also ordered new TPMS valve stems, as they aye corrode, so I always renew them every time that the tyres are off.

The reason I asterisked the fitted price is that I've actually got a tyre changing machine and balancing machine in the workshop, so I was initially looking for a price for the tyres delivered, and I'd fit them myself, but with the delivery charges, it was only a few quid cheaper to get them delivered rather than fitted. For the sake of a few quid it wasn't worth my time or effort to get the tyres sent to the house, put them in the car, take the car to the workshop, take the tyres out of the boot, take them upstairs to my machines on the mezz-deck, take the wheels off, take them up to the mezz-deck, change over the tyres, balance the wheels, take the wheels down the stairs, take the tyres down the stairs, fit the wheels, then have to pay to dispose of the tyres. (Scotland have different and more stringent rules on disposal of tyres)