New C5 owner with a few questions already

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bobins
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Re: New C5 owner with a few questions already

Post by bobins »

With the right tools and set up, lowering the subframe isn't actually that hideous - I had to do it to get my steering rack out.
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KennyW
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Re: New C5 owner with a few questions already

Post by KennyW »

Dropping the subframe is not that bad. It sounds worse than it actually is.

I've had to do it several times. steering rack , wishbones etc.

Kenny
aerodynamica
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Re: New C5 owner with a few questions already

Post by aerodynamica »

I get the feeling I'll have to do it at some point in the C5 experience :)
Gibbo2286
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Re: New C5 owner with a few questions already

Post by Gibbo2286 »

If as you say you can get it out once undone I suppose a hammer and punch on the edge might shift it enough to loosen it to hand tight.
aerodynamica
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Re: New C5 owner with a few questions already

Post by aerodynamica »

I was out on a longer journey today and have noticed another fault/quirk. It seems that each time the windscreen washer is used on the motorway about 10 seconds later the windscreen slightly fogs up inside and then clears. I suspect water is getting in the air intake below the windscreen but where/ why? Or perhaps the windscreen is made briefly colder by the water? Seems unlikely. I wonder if there is water sitting in that area below the windscreen.
hattershaun
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Re: New C5 owner with a few questions already

Post by hattershaun »

aerodynamica wrote:
30 Dec 2021, 19:02
I was out on a longer journey today and have noticed another fault/quirk. It seems that each time the windscreen washer is used on the motorway about 10 seconds later the windscreen slightly fogs up inside and then clears. I suspect water is getting in the air intake below the windscreen but where/ why? Or perhaps the windscreen is made briefly colder by the water? Seems unlikely. I wonder if there is water sitting in that area below the windscreen.
The HVAC system goes into recirc mode for a short while when you squirt washer fluid, all part of the normal behaviour (& a/c will be activated if not already on.)
Are you running with the aircon turned on all the time? If not, that could be why you get some condensation for a short period.

When the engage reverse gear, recirc mode is also activated.
The joys of clever modern multiplexed cars!
aerodynamica
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Re: New C5 owner with a few questions already

Post by aerodynamica »

hattershaun wrote:
30 Dec 2021, 19:38
aerodynamica wrote:
30 Dec 2021, 19:02
I was out on a longer journey today and have noticed another fault/quirk. It seems that each time the windscreen washer is used on the motorway about 10 seconds later the windscreen slightly fogs up inside and then clears. I suspect water is getting in the air intake below the windscreen but where/ why? Or perhaps the windscreen is made briefly colder by the water? Seems unlikely. I wonder if there is water sitting in that area below the windscreen.


The HVAC system goes into recirc mode for a short while when you squirt washer fluid, all part of the normal behaviour (& a/c will be activated if not already on.)
Are you running with the aircon turned on all the time? If not, that could be why you get some condensation for a short period.

When the engage reverse gear, recirc mode is also activated.
The joys of clever modern multiplexed cars!
Hiya Shaun, ha that's fascinating! I suppose it's to prevent you breathing in vapour that's filled with screenwash. Ditto when reversing to maybe stop exhaust coming in?

I do have the aircon on all the time, the bit of fogging lasts for a few seconds at most
aerodynamica
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Re: New C5 owner with a few questions already

Post by aerodynamica »

Back to the questing of lowering the front subframe. I looked at some threads about lowering it and it SOUNDS straightforward. My main concern is the big mounting bolt I can see roughly mid way from front to back of the subframe. It looks large and rusty at the top. And I'm not certain what it screws into (large captive nut/ weldnut?) And I'm concerned this will break or the item it screws into will break.
Also, how high must the car be raised and how low does the subframe actually lower? I can only raise the car as high as driving up on ramps, suspension raised and axle stands.
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KennyW
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Re: New C5 owner with a few questions already

Post by KennyW »

Graeme,

The sub frame mounting bolts are screw into either a captive nut or welded nut but if never undone the will break or be broken.

I got my off reasonably well first I soaked them well with plusgas or similar then used I think a 21mm ring spanner on the nut with a 24mm socket,breaker bar extended with a scaffolding pole to loosen them off. My impact wrench the first time couldn't budge them.

I hope this helps.

Kenny
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Re: New C5 owner with a few questions already

Post by aerodynamica »

Hi Kenny thanks, hm I have a 6' breaker bar and 22mm spanner available. But if the bolt breaks....

I was also concerned that if the subframe is lowered it might allow the physical removal of the front suspension regulator but the lowered subframe might be in the place I need to lie to actually undo things....

Might be easier to take out the engine 🤣
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KennyW
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Re: New C5 owner with a few questions already

Post by KennyW »

Graeme,
The bolts are quite robust so I think they will be okay. Make sure the spanner is the exact size. The bolts thread are mostly protected by the mounting bushes in the sub frame.

I suspect you will have to remove the sub frame from the car to get the regulator. Good luck.

Kenny
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Re: New C5 owner with a few questions already

Post by aerodynamica »

I'd get the plus gas on them a good time in advance.

I wonder about the subframe having to come all the way off. I think because I can remove the pipes from the regulator then it's simply the physical space to get it out that's the issue. I had checked and the lot will not come out any of the available spaces. If I'm doing the subframe method I'm going to have to really concentrate on the order of what gets loosened before the subframe. Does the steering rack remain bolted on the subframe for this?
20220108_113455.jpg
this view is the largest access space avail. Even a sphere on its own can't fit through this.. I've tried
this view is the largest access space avail. Even a sphere on its own can't fit through this.. I've tried
And the new regulator is just waiting...
20220108_155745.jpg
This regulator was originally bought to replace the really rusty rear one but that plan might now have changed.. painted in caliper paint to give it a bit of a chance not to rust..

Still, my new pair of rear pipes arrived from Lithuania!
20220108_170720.jpg
These two along with the new PAS pipe are nicely solid and I'm thinking about how best to protect them. I considered powder coating but the rubber sections probably cant take the 200+ degrees. I am considering a base of zinc primer, possibly several layers and then top coats but what to use to top coat them. The reason I think large diameter pipes etc and rear spheres rust so much is that I think they actually stretch microscopic amounts but enough to cause the paint to crack. Well, they didn't bother to paint the C5 pipes or that PAS pipe - it's just metal. All my Xantias and XMs had plastic coated hydractive pipes.
aerodynamica
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Re: New C5 owner with a few questions already

Post by aerodynamica »

Updates too on the wiper motors. I bought the C5 with non functional wipers and after a saga of trying to source a LH one I ended up buying a brand new RH one in the mean time and decided to refurb the functional RH one on the car. The fault of course, was with the left unit and they're unobtainable and S/H ones are going for daft money. I then did manage to source not one but two LH motors though. Both work fine but the first one I got off a breaker on ebay and have been running since the second week in december, had been hitting the windscreen pillar trim lately. I thought I'd attached it wrong although I'd used the markers on the glass. It turns out there is a lot of free play in the mechanism of that motor. I did however have a second motor from ecoparts, a large online breaker. Theirs was tested on the car and worked well and there's no play in the linkage. I opened the top cover of the first replacement motor and to see where the play was and sure enough it's in the metal linkage. The linkage was brown with rust/water mixture and the pivot bush had worn and enlarged the circle of the link. So water gets in everywhere on these motors. I decided to go ahead with my project of improving the water sealing of the motors. The first problem I noticed after opening up the original failed motor was the terribly small seal for the ECU and the alloy casting it is mounted in. Furthermore the casting is very thin. The area where it leaks is obvious - the seal length along the edge where the motor and the multi plug are. I note that the plug overhangs this seal and water can easily sit under there. It seems that it is actually the corrosion of the alloy that's the culprit.
My plan was to coat the outer surface with paint-on roof sealant to completely cover the alloy surfaces and the edge where the seal is. I note the ECU part of the housing looks like it's intended to act as a heat sink too so I chose not to paint the small finned part. No idea how hot this ever gets but best avoided. I also noticed the RH motors had a rubber flap that has a cut out for both the upper mounting leg and the wiper spindle. Unless mine is missing and the two replacement LH motors too , the LH unit doesn't come with one. I can't see why the RH would get this and not the left so I decided to fit the spare RH motor's flap to the LH side. So it's painted with roof sealant (the stuff that claims to be able to seal a leak while it's actually raining..) and it has a rubber flap cover now. My hope is this will mean the LH motor remains protected indefinitely. I also fixed the broken clips for the ends of the scuttle plastic cover as they allowed the part above the motor to drift up a bit from sealing against the glass.
Coated with roofseal
Coated with roofseal
Coated with roofseal
Coated with roofseal
In place with rubber cover too
In place with rubber cover too
It is incredible that they arranged it so that water can run off the windscreen directly on to each motor.... but as magnificent as I find the X7 I am startled by some of the insane arrangements I find on it. Omissions like the lack of warning for the washer fluid level (or is mine just not functional) even my old XM had that. Just annoyed because I ran out of washer fluid :)

Just as an illustration of how little help these wiper motors need to corrode. The next pictures here are of the brand new RH motor that has done just under 6 weeks' service and has gone from pristine condition to the beginnings of surface corrosion..
New RH motor
New RH motor
the beginnings of corrosion on the alloy surface
the beginnings of corrosion on the alloy surface
the beginnings of corrosion on the alloy surface
the beginnings of corrosion on the alloy surface
Anyway, I have got functional wipers now so I just want to try and keep them this way.
aerodynamica
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Re: New C5 owner with a few questions already

Post by aerodynamica »

And there's more!

Here's a pic of the front regulator in it's nice rusty state.
20220108_113515.jpg
I found out to my dismay that although the previous owner told me the long front to rear hydraulic pipe was replaced and I'd seen the nice copper nickel pipe at the rear. I can't see it at the front and indeed the pipe as it connects to the BHI unit is black coloured. This means that they must have joined it somewhere amidships.... My plan was to replace it completely but speaking to Pleiades they tell me they currently cannot make C5 pipes up because of a shortage of the ends. I did get a cut-off pipe with that new front regulator so I thought I'd see if it would take an LHM era pipe end form - and I've got the former- so here's a little trial. Initially I was using the cut pipes to plug the ports for painting until trying this.
20220108_170802.jpg
I'm thinking of simply doing this to either end and getting a length of 3.5 Cupro - Nickel pipe and standard Citroen straight joiners. I think someone (maybe Kenny) did this too? I've heard of some people using compression olives but since I have the old style pipe former I think I'll use that..

Here's what I'm dealing with at the rear:
20211218_170658.jpg
You can see the copper pipe from the union at the lower right. The regulator and rear suspension pipes are very rusty - I'd quickly painted them in black hammerite to try and slow the inevitable and get through this winter - it's hard to see how it passed last year's MOT.. this is what I intend to fix with those replacement rear pipes. Also, anyone know what the black plastic pyramid thing near the anti roll bar is?
aerodynamica
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Re: New C5 owner with a few questions already

Post by aerodynamica »

Few details about the front regulator:
As it arrived, sphere was incredibly tight to remove
As it arrived, sphere was incredibly tight to remove
Pipe unions and accumulator flange
Pipe unions and accumulator flange
Pipes off to look at the ends - can anyone form the 3.5 pipe end?
Pipes off to look at the ends - can anyone form the 3.5 pipe end?
Front hydractive 3+ damper valve  -much like Hydractive 2
Front hydractive 3+ damper valve -much like Hydractive 2
Damper valve
Damper valve
Best measurement of the damper hole out of interest
Best measurement of the damper hole out of interest
The C5 Front H3+ firmness regulator damper center hole seems to be about 1.8mm, the rivet is etched with 5 - 4. It looked visibly larger than 1.8mm but could have been an illusion. Compared to the 1.3, 1.25 ( if I recall ) on the Xantia Hydractive rear and front firmness regulators this would be a lot different. I think the Xantia ones were etched with '2 - 6'.
Xantia Hydractive damper
Xantia Hydractive damper
Xantia Hydractive damper
Xantia Hydractive damper
Of course it depends on the actual volume of fluid moved for a given vertical stroke of the suspension cylinder.