xantia water leak

Post by **graham593192** » 04 Feb 2008, 18:45

I have a water leak on my cylinder head and just wondering how much of a job its goin to be to fix it.

It appears to be coming from some sort of hole/indent between spark plug 1 and 2 or 3 and 4 depending which way they are numbered.

I had trouble starting it last night but got it going eventually. i've done about 60 miles today on motorway and it was running rough as though it was missfiring.

I had the ignition coil block off and spotted a pool of cooling water in the channel between the camshaft blocks where the spark plugs are. i mopped the water up and saw that the water was coming from one of these holes.

What are the holes for? Is it going to mean taking the complete head off and repairing/replacing?

Xantia 1.8 16v Vreg (1999)

Post by **graham593192** » 04 Feb 2008, 22:04

I've just spoke to a friend about this and he mentioned that they may be core plugs he said he had an old car which had these and they were designed to allow for water expansion if the coolant freezes and were designed to move or even pop out if the water froze rather than it cracking the block.

Does anybody know if citroen fit anything like this and if it's likely to be whats happened to mine?

The car hasn't moved all weekend and its been rather cold in an evening. Looking at the colour of the coolant I don't think there's much, if any, anti freeze in the coolant so my initial thoughts were that it had frozen and perhaps cracked the block.

Rather disappointing as when I bought the car 3 months ago it came with a fist full of invoices for services at the recommended intervals and I assumed must have been changed recently. I know know I should never assume anything and am now wondering if the cambelt has ever been changed but it looks like I'll be changing this anyway if I'm going to have to take the head off.

citronut · Post by **citronut** » 04 Feb 2008, 22:28

im not sure were the core plug are exactly on a 16V head but it dose/will have some, if you can find an exploded scematic of the head it should show were they are,

they also go by rustting through

regards malcolm

Post by **graham593192** » 05 Feb 2008, 10:31

Having looked at an exploded diagram of the cylinder head on service.citroen I can see they are called 'welch plugs' there are 3 or 4 of these in various places around he cylinder head.
DOes anybody know what these are for? Can i get them out with out taking the head off?

citronut · Post by **citronut** » 05 Feb 2008, 13:34

they are partly for expantion if the coolant freezes, but i also belive they are some thing to do with machining the head when it is made
,

and yes you can replace them in situe if they are accesable, normaly stab them with a small chisele and prize them out beeing very carefull not to damage matting surface
regards malcolm

steelcityuk · Post by **steelcityuk** » 05 Feb 2008, 14:03

Maybe they are part of the casting process? Should a sealer be used when replacing them?

Steve.

Post by **graham593192** » 05 Feb 2008, 14:29

New plugs on order from citroen at 22p each!! Car is out of action for few days tho until they arrive.
Just wondering if I ought to use some sort of sealant/epoxy/chemical metal when I replace them as i'm never going to get them as tight as the original which I assume were pushed in by machine.

Also why would this cause the engine to run rough? Surely its more likely to over heat as the coolant is dropping. Or is it that there's moisture in and around the spark plugs and ignition block?

jgra1 · Post by **jgra1** » 05 Feb 2008, 17:17

Moisture anywhere near plugs will cause misfire Graham..

John

Post by **graham593192** » 05 Feb 2008, 19:47

Thanks for the info. Hopefully everything will be sorted once the bits arrive from citroen.
Had the rdiator out and given it a good flush through as well as the engine block while I've got it in bits.
Couldn't find a drain on the front of the engine block which my old xantia had. Also how do I drain what is in the heater matrix? There wasn't as much water come out the engine block as i was expecting if the heater matrix was to be drained as well.

Clogzz · Post by **Clogzz** » 06 Feb 2008, 14:24

Think they weren’t fitting engine block drain plugs on that vintage anymore … splitting pennies.

The matrix can’t be drained at all.
The reasoning is that if the coolant change is done as and when specified, it’s good enough.

citronut · Post by **citronut** » 06 Feb 2008, 19:14

you shouldnt need any sealer at all as they are slightly tapperd, just tap them into place maybe useing a socket of the wright size as a chaser just a bit smaller than the top edge of the core plug
regards malcolm

Post by **graham593192** » 19 Feb 2008, 23:01

Ok. I've fitted the new core plugs and changed the coolant etc and the leaking head seams to be cured but it's still running rough when the engine gets warm.
It seems to pull ok when its cold but once its warmed up (75degrees) it still seems to be miss firing when I put my foot down. It'll cough and splutter for a few secconds and then pull ok. Also if i keep the revs up over 2.5 - 3k it seems ok but then when the revs drop it starts missfiring again.
Any ideas?
I've got new plugs which I'll fit tomorrow but not sure where to start looking if its anythin more serious. Chucked a bottle of rad weld in toniht before heading home incase it was just a small hole somewhere but it ws still missfiring after driving 25 miles home so guessing that hasn't done much.
What are the possible symptoms of the head gasket going? I now about milky oil etc but are there any other symptoms? I've stripped the head and changed the complete engine on a previous car but don't really want to start pulling this one to bits if its not necessary as I haven't really got 3 or 4 days to be messing with it and having the car off the road.