Re: Xantia HDI 2.0 90CV 2000 Mystery coolant system part!!!

FRJoey46 · Post by **FRJoey46** » 17 Dec 2016, 13:37

Hello all,seasons greetings! Once again the French have me baffled,a very slow leak of coolant has been going on for months. My good mechanic located it,I pointed out how evaporating coolant was coming out from behind the longest part of the plastic air intake tube behind the engine.With a torch I spotted the drip myself but this time it's a mystery car part. It is not in the manual and won't appear on any web search under French name "bloc rechauffer".It has four leads coming out the top that look a bit like heater plugs and a coolant hose either side. ..not miles away from the matrix leads.it is a small alluminium type block and the drip is from below,not the hoses or leads on top (possibly electrical). I beg you all for the English name of this part!my mechanic has never had to change one before,I'm just extremely lucky. Cheers guys

FRJoey46 · Post by **FRJoey46** » 17 Dec 2016, 13:39

Furthermore...I heard of a metal sealant epoxy. Could that fix the issue as it seems to be the alluminium leaking?!

Post by **GiveMeABreak** » 17 Dec 2016, 14:04

FRJoey46 wrote:Hello all,seasons greetings! Once again the French have me baffled,a very slow leak of coolant has been going on for months. My good mechanic located it,I pointed out how evaporating coolant was coming out from behind the longest part of the plastic air intake tube behind the engine.With a torch I spotted the drip myself but this time it's a mystery car part. It is not in the manual and won't appear on any web search under French name "bloc rechauffer".It has four leads coming out the top that look a bit like heater plugs and a coolant hose either side. ..not miles away from the matrix leads.it is a small alluminium type block and the drip is from below,not the hoses or leads on top (possibly electrical). I beg you all for the English name of this part!my mechanic has never had to change one before,I'm just extremely lucky. Cheers guys

Can you post up your VIN and I'll post up a Diagram for you.

Gibbo2286 · Post by **Gibbo2286** » 17 Dec 2016, 16:08

I think your French means something like re-heat so maybe a re-heater block/part

Stickyfinger · Post by **Stickyfinger** » 17 Dec 2016, 16:46

After market water heater for winter ?

FRJoey46 · Post by **FRJoey46** » 17 Dec 2016, 17:14

VIN is either X1RHYF or MCT5202AD444
OR VF7**************[VIN obfuscated, can be read by forum staff]. Sorry to be so unsure. ..I have found the block though so unless their is a part number or something I'm still lost without a name.
Yes the literal translation is indeed reheating block but I'm my experience the English terms for car parts are totally different. For example what the French called a maitre cylindre (master cylinder)was actually my brake control valve in English. Hymmph ,France is frustrating.

Post by **CitroJim** » 17 Dec 2016, 17:17

That's the electric auxiliary heater. So fitted because the HDi takes so long to warm up in the cold on account of how efficient it is... The unit is just downwind from the heater matrix and is intended to provide immediate hot coolant for demisting purposes.

Those are shocking for springing a leak when the coolant is changed if there system is not very carefully bled. If there is air in the housing when the heater plugs go on - they go on as soon as the engine starts - the housing will rapidly warp and spring leaks...

Seen it happen and seen just how quickly it happens too. They're not the most accessible and hard to get at to change.

It is critical to make sure the heater matrix, the auxiliary heater and the pipes are bled as far as possible before the engine is first started after a coolant change. Also, remove the heater supply fuses until you know the system is 100% fully bled.

Post by **GiveMeABreak** » 17 Dec 2016, 17:32

I'll post up what I thing the right Diagram is and perhaps Jim or yourself can confirm if I've got the right diagram:

Cooling System

Water Reheating

Post by **white exec** » 17 Dec 2016, 19:11

Not seen one of those before.
The unit looks almost as if there are four (?) glowplug-type heaters screwed into it.
Don't normally associate glowplugs with liquid heating - but no reason why not.
No wonder the unit responds badly to an airlock in it!

As a general observation, I think the proper procedure for coolant bleeding our engines is not well understood.
Oddly, it was one of the things Haynes usually detailed properly, including the use of a temporary "header bottle" in some cases.
Could be the basis of several "How to..." diagrams, maybe.

Post by **GiveMeABreak** » 17 Dec 2016, 19:53

I'm not even sure if I've got the right diagram - a bit hard from the OPs description Chris - but hopefully somebody in the Xantia 'know' will be able to work out if the part is there - or not!

Post by **KennyW** » 17 Dec 2016, 20:12

No 6 in the 2nd diagram is the re heater

http://service.citroen.com/docapv/affic ... efaff=0291 06 642607&idFct=FCT0346

If my link works you can see the hoses 1.from engine to re heater 2. to matrix and then to plastic pipe on the bottom to the back of engine block (PIA to remove and get to)

Kenny

Post by **RichardW** » 17 Dec 2016, 20:40

I cooked the heater in mine after changing the water pump. You will see in my info about changing the cambelt a warning to be very careful of cooking this block.... Dickie G did the same, and changed his; as explained in this thread: https://www.frenchcarforum.co.uk/forum/ ... hp?t=35160

Post by **CitroJim** » 18 Dec 2016, 06:12

Marc, the diagram you posted is for the later HDi with the Erberspacher diesel powered auxiliary heater... had one of those.. Great fun!

RichardW wrote:Dickie G did the same, and changed his; as explained in this thread: https://www.frenchcarforum.co.uk/forum/ ... hp?t=35160

I was there with Dickie when it happened

Neither of us appreciated then the risk...

FRJoey46 · Post by **FRJoey46** » 18 Dec 2016, 09:05

Fabulous findings from all you chaps! I confirm also it's the second diagram part number 6. Should be extremely useful when I ring Citroen parts in Diss tomorrow. Interestingly...it was my mechanic who did the last coolant change BUT he did that for free while doing can belt. Nobodies perfect and sounds like an easy mistake.That said he better get it right this time! Looks like changing the bit is possible if you get the plastic air intake right out. Thanks to you all,bloody good chaps.

FRJoey46 · Post by **FRJoey46** » 18 Dec 2016, 09:11

To "GiveMeABreak" thats brilliant....where can i actually find the parts catalogue that these detailed pics are from? I salute you.

thanks

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