Activa dumped all it's LHM

[CitroJim]

I'm stuck!

Between a rock and a hard place but not in hard mode

James, open the ECU box and remove the two connectors on the Hydractive ECU. That'll do the trick..

I don't understand you and Dom's F8 business. I've looked at all the diagrams I have and all say F8. Most odd...

[Stempy]

Try cabin F15, works for me...

[Sl4yer]

Thanks Jim and Stempy.

I'll try F15, then the drastic route! Or possibly a long 'trial and error' session first. I've already done all the 20A and 30A ones in the engine fusebox.

James

[KevMayer]

Quote: "OK, bad news. Don't know what I was looking at yesterday, but it looks totally different today! Can't see anywhere for a missing pipe.

With the engine running, the LHM runs along a cable conduit to the right of the Hydractive sphere block, then down onto the ram. I can't actually see where it's leaking from, but it's a steady pour. Access is terrible, and this won't be a repair which I can tackle."

When I removed my rear ram for inspection some time ago I removed the ram along with the two hydraulic hozes which feed it. I found that one of the hozes had been abraided where it had been rubbing on something. I covered it in sleeving and taped it in place to protect it but I could see that in time it would have punctured. When I refitted the ram/hozes I made sure the hoze was free of any structure.

So, I wonder if your leak could be from a split in one of the ram hozes. This would give you a continuous flow of LHM.

This isn't such bad news because these hozes are fairly easy to replace.

[CitroJim]

That's a good point Kev. There's a heck of a pressure in those hoses so I'd expect a split to eject LHM in a fierce jet rather than a dribble but if it's not quite gone all the way through it will seep. Seen that on the rubber section of a damaged power steering pipe.

The ram flexi hoses are two hoses in one with the lower layer separated by a steel braid.

There is a real risk of abrasion of the front ram hoses if they're not properly laid.

This picture is typical of the abrasion wear. It shows the internal steel braiding. I caught it before it sprang a leak...

[Sl4yer]

Thanks for the input Kev. All ideas really are welcome!

The first sign of the leak is LHM pouring from an electrical conduit behind the Activa pipe where the arrow is in the pic below:



I'm sure it's a leak on the electrovalve, or else a hole in one of the pipes to it.

It seems pretty clear from this arrangement how the Activa system was very much an afterthought! How much simpler would it be if the Activa and Hydractive valves were swapped?

James

[KevMayer]

This image shows the rear hydraulics of the Activa.

The pipes on the hydractive block are 1&2 for the feeds to the struts. 10&12 are small bore pipes from the anti sink valve. The only pipe not shown is the rubber return pipe.

The two ram hozes are 6&7.



I'd be inclined to strip out the hydractive block assembly and take a look at all the stuff in that area. I've done this once already on my Activa and it was reasonably straight forward. Where abouts are you? If you were in my town I'd pop around and get under there with you.

[CitroJim]

James,

I'm with Kev here, if I knew where you were and not too far away, I'd be there too!

The arrow points directly to the area of the ram pipe unions.

Just above here is a 5-way junction that carries the cylinder returns. Activa electrovalve return and the ram return. It does not carry the hydractive electriovalve return.

It can split.

Here's a picture of it showing it's proximity to the hydractive electrovalve. The shot is not an arty vignette, it was taken through a hole in the floor that was cut for easy access.



Seems a tin opener is a useful tool to have with an Activa

[KevMayer]

Here's the layout of the rear return pipes:-

[Sl4yer]

Thanks guys! I'm in north Manchester, so not local unfortunately.

Jim, that return union looks to be in the perfect position for the leak! But not in the perfect position to fix. (I like your arty photo BTW! ) Why on earth did they put it there?!

Is there a guide to removing the Hydractive block anywhere? I haven't come across one in my searches. And what tools would I require? (I'm not keen to cut a hole in the floor!)

James

[CitroJim]

I have to confess, James, it was not my photo. It was taken by someone who had a similar issue to you but in his case it turned out to be a split half-way along the hydractive valve return pipe, near the middle of the subframe.

The hydractive block is not too bad to remove but is made a little complicated by the ram flexi pipe bracket being mounted above it.

Remove sphere. Undo the big 17mm hydraulic unions; you MUST use a good 17mm Hex Flare Nut Spanner or you risk rounding them. You'll need to remove the whole pipe that goes to the RH wheel cylinder to make it possible to withdraw the block.

Disconnect the electrovalve electrical plug and leakage return pipe.

Undo the 8mm hydraulic pipe unions.

Undo the nuts that hold the ram pipe bracket to the top of the block. Then undo the three studs that the bracket attaches to. These hold the block to the subframe.

Even if you do that, I don't think access will be much improved as the junction itself is on top of the subframe.

I don't know about here, but in France the junction is marked as NFP. (i.e. no longer available).

Hopefully, a pipe has popped out of it. If you use a dental mirror or other small inspection mirror, you should be able to get a view of it from below. Try going up through the round hole in the top of the subframe.

It's better (and actually easier) to drop the subframe a tad. Undo the four mounting bolts, have a trolley jack under each end and gently and carefully lower. The hydraulic pipes will "give" just enough.

You're right, the Activa bits were very much tagged on as an afterthought. Not much design there!

[landcrab]

If you are in Manchester you could give Doug a ring at Westroen and if you could get to Chorlton he would sort it for you.

He's always worth talking to about suspension problems.

[KevMayer]

One option to get to the leak back joint block would be to lower the rear subframe slightly by partially undoing the four securing bolts.

I did this recently when I overhauled my rear arm bearings. I read it in a post as a recommendation to improve access to the ABS sensor connectors on top of the subframe. It worked a treat and gave me an inch or so gap.

If you remove your hydractive block and then lower the subframe a bit you will probably be able to work on the leak back pipes.

EDIT: Sorry Jim .. I didn't finish reading your last post and the bit about lowering the subframe

[Sl4yer]

Good news and bad news I suppose...

The good news is that F15 in the cabin fuse box did indeed stop the valves operating. Of course, as expected following Jim's pics yesterday, this didn't stop the leak.

The bad news is that it is definitely coming from the area where the joint is located (up above the subframe). Access is indeed awful, and I now know why one might cut a hole in the floor! I can see how lowering the subframe would be the best option.

This job is probably beyond my capabilities and experience, and certainly beyond the equipment I have. I'm taking the C3 for it's MOT tomorrow, so I'll offer the job to my regular garage (the owners have had Xantias before, and have tackled other basic work well). If they don't want it, I'll try a Cit specialist in Todmorden.

Landcrab, thanks for the tip about Westroen. I thought they were only interested in spheres, although their web site now says they'll supply and fit height correctors to. One to bear in mind...

Thanks for all your help guys. I'm hoping this won't cost the earth, although Activa ownership can be like that.

James

[Stempy]

Thanks for all your help guys. I'm hoping this won't cost the earth, although Activa ownership can be like that.

James

I think Xantia ownership in general can be like that