Expansion Tank - Xantia 2.1TD

Raj · Post by **Raj** » 16 Jul 2008, 14:30

Hello All,

Anyone breaking a Xantia 2.1TD?

Im looking for a replacement expansion tank... mines leaking a fair bit of coolant through the seam where the two halves meet.

My bank balance can't withstand a trip to the dealer, wouldnt like to guess what they'd quote.

Or can anyone suggest alternatives for a DIY fix?
Maybe this Radweld or K-Seal stuff... although I am a bit weary about using these.

Its a long shot but can these tanks be repaired?

Cheers.
Raj

Xantia 2.1TD 1997 - 133,000mi

Post by **CitroJim** » 16 Jul 2008, 14:43

Hi Raj,

Welcome to the forum

The only other Xantia I know that uses the same expansion tank as the 2.1TD is the V6 so that's not really very helpful - sorry!

As for repairing the tank, the plastic they are made of is notoriously difficult to stick with anything and it is unlikely to stem the flow. the kind of failure is not going to respond to K-Seal either unfortunately.

There is nothing intrinsically special about the tank and a similar one from other PSA vehicles should fit reasonably until a pukka 2.1 item shows up. I'm thinking the black tank fitted to late model Pug 205s are very similar, it should do and scrapyards normally have a fair selection. Who knows, a scrapyard visit may well show up another PSA vehicle that uses the exact same tank.

AndersDK · Post by **AndersDK** » 16 Jul 2008, 15:42

For a plastic bottle the pricetag is rather hefty (thefty ?).
Some £45 ex vat.

You may use any type 2-component epoxy repair sealer. Thats about anything that will stick onto the bottle and seal it.

DickieG · Post by **DickieG** » 16 Jul 2008, 17:12

These tanks are very poor in they way they are bonded at the seam, my V6 is now on its third one in just 55,000 miles so the chances are that any you discover in a breakers will be just as bad. As Jim suggests, I can't imagine radweld or similar sealing the leak.

Post by **myglaren** » 16 Jul 2008, 18:07

Depends rather on what material they have used but there are solvent bonding agents that may work on it.
I have used a Marley plumbing solvent adhesive in the past that has worked very well. I'm having difficulty locating it on the net but a plumbers supply warehouse should stock it. Try a PTS if there is one local to you.
You may also be able to heat weld it but that is a bit specialised and could go horribly wrong,

Post by **xantia_v6** » 16 Jul 2008, 21:38

As you might expect (it is intended to contain boiling water at pressure), the tank is not made of thermoplastic, and it does not seem to respond in any useful way to application of heat to the seam.

I would speculate that it is made by sandwiching a layer of sealant/adhesive mateirial between the 2 halves of the tank, and this sealant/adhesive layer fails under the heat/pressure cycling, causing the leakage.

I have tried cutting a 2mm wide x 4mm deep channel along the seam, and filling that with a high temperature silicone sealant, but the sealant did not adhere well enough to the plastic to be of any benefit.

I imagine that the tanks would be a bit cheaper if sourced from the original manufacturer, but I haven't found a source on the internet.

davethewheel · Post by **davethewheel** » 16 Jul 2008, 23:32

i tried to find a cheaper alternative when the one on my xantia 2.1td split, but had to give up and pay the main stealer price £48.00
seems like a very bad idea making a expansion bottle made out of 2 halves stuck together.

Raj · Post by **Raj** » 17 Jul 2008, 11:10

A big thanks to all who replied...

I tried the DIY heat seal method with a butane blow torch... wouldn't recommended!
It looked as though I'd melted the seam closed, but it wasn't long before the coolant leaked through again.

Will hunt down some of this plumbing epoxy / solvent and see if that does the job... otherwise its a case of either regular top-ups or "grand theft auto" at my local Citroen dealer.

Raj