Water Leak Into The Boot, what a pain

[noz]

Hi all,

I decided a while back to try to trace the source of the water leak into the boot of my XM. I took the carpet out about three weeks ago, washed it and got it dried in the nice weather we were having. I then waited for the rain which didn't come for another 5 weeks!

I was never sure if the water ingress was simply by gravity from above or whether it was being splashed upwards from the wheels whilst travelling. Well, about a week ago it rained overnight for the first time in weeks. Therefore I could be sure that it was not related to wheel splashing. I opened the boot lid after a night of heavy rain to see the pool of water in the little hollow where the wheel nut key is kept. I traced it upwards and it disappeared upwards somwehere. To trace it further i removed the rear off-side light cluster.

The back wing incorporating the rear quarterlight is a complicated affair with layer upon layer of metal pressings all spot-welded together. Because it was still raining when I checked, the water was still dribbling in. It is coming down a narrow channel which can be seen up through the hole left when the light cluster is removed. From what I could see it seemed to be flowing down hill from the top corner of the quarterlight (triangular shaped rear window).

I had a look to see where it could be entering the channel from the outside. You have the rubber moulding which forms the edge of the glass running all the way from the waistline to the roof. You also have the rubber strip travelling the length of that odd little piece of body about 300mm long x 40mm wide (in the attached photo). Has anyone ever tried to remove this little section of body? If so, how does it come off? You also have the point where the cables cross between the tailgate and the body. The body is rusty at this location on mine.

When I get a chance over the holidays I'm going to take some food colouring and starting at the bottom release some dye into the water and watch for it appearing in the boot. Each time I'll pour some dye and look for a leak. If nothing is found I'll move a little higher and try again. I'll keep on repeating that all the way to the top of the tailgate. I'll have nothing better to do anyway.

All three of my XMs suffer water leaking into the boot. Although I've looked for the leak before I've never done it so methodically and hence was never sure how it was getting into the boot believing it was coming in lower down. Having heard others complain about the same thing leads me to believe this is a common complaint and therefore a design/manufacturing issue. I'm determined to find the source because its a real pain having a soaking carpet all the time, not to mention the additional rust source. Of course finding it is only the start of the process. Whether anything can be done about it is another.

I'll keep you posted on the results.

Cheers

noz

[cromponz]

I found one waterleak in my XM. It started as just an annoying little puddle, then intensified as time went by. Gradually the mouldy smell of damp carpets got the better of me so last Christmas I made a concerted effort. After much hose playing I discovered water coming out the headlining. Although the sunroof looked fine with no visible signs of rust, I decided to remove all the headling and check it thoroughly.
It was a mixture of delight (finding the cause of water) and dismay (at the repair work that lay ahead). Each corner of the sunroof bucket has drainage hoses which run out below the car. And the rear two had rusted away with the hoses sitting adrift in mid air.
A good few days later and the two offending areas are now repaired and leak no more. But I do admit that occassionally there is water seeping through but in another place, (right hand rear corner). I wonder if, with age, seals around the boot lid and the lower step are not as pliable as when new. It could be capilary action that enables the water to travel.
More time is required with me laying inside the boot with the linings removed, and another person outside, playing the hose in various places.

[xmexclusive]

Reported sources of a wet boot floor that I have seen are:
Tailgate top and side channels blocked with crud.
Displaced or split tailgate rubber seal.
Wiring rubber covers no longer sealing because they have been butchered to repair the broken wiring.
Rear sunroof drains.
Wing Tail light cluster wrongly fitted.
Entry under pressure due to floor holes.
Capilliary feed from a wet back seat floor pan.
Leaking rear screen wash feed.
Radio aerial leakage feeding round the trim.

One of the major problems in pinpointing water source is that Citroen used thick open cell structure foam underlay under all the cars carpets. This can absorb and retain large quantities of water while its plastic top layer still keeps the carpets dry. This foam can also move the water on by capilliary action.
Strip out the boot and search is the only way.
Like the idea of dye tracing.

John

[bobhalliday]

Hi Noz.

My last XM saloon Mk1 developed a leak that took me a long time to pin down and I found one rainy day when I was inside the stripped down rear end, I leaned against the side and felt water on my back! It turned out to be the rear plastic tube, the drain from the sun roof, and it was kinked and burst. I had a legnth of green reinforced plastic hose which the clear plastic drain was a tight fit into, I super glued a four inch piece onto the plastic, (which I had cut) and that worked fine for about four years.
My currant Mk2 XM Estate got a bad leak into the back seat footwell O/S. there was gallons in there! Took days to dry it out! That turned out to be the sunroof drain too! But it's on the outside above the rear doorway and is just a rubber channel that directs the water to the lower end of the rear doorway. I had destroyed the channel with my shoulder rubbing on it. It's been taped up with selotape for ages now.

Bob