Xantia head gasket blown

JamesQB · Post by **JamesQB** » 21 Mar 2009, 20:06

Hi all,

My parents' Xantia is in trouble again. It's the 1.8i 8-valve petrol version. The radiator was leaking and whilst out driving the engine overheated. When they had a look under the bonnet, it was clear the head gasket had blown, there was oil seeping from the junction of head to block.

My concern is that if overheating caused the head gasket failure, then the head might be warped. Is it guaranteed that it'll be warped if overheating causes the failure?

Wondering if anyone here has experience of this... how much does it cost to get the head checked for flatness, and how much to get it skimmed if that's necessary? I have heard that if only a small amount is skimmed, you can use a standard head gasket, but if more than a certain amount is taken off, then you need a thicker gasket. Any ideas on where thicker ones are obtained and the cost?

Basically trying to ascertain overall costs to see if it's worth repairing.

Thanks,
James

Post by **CitroJim** » 21 Mar 2009, 20:19

That's unusual on an 8V James...

They can be skimmed no worries and checked very easily. No need to get the specialists in. Just clean up the surface and lay a straight-edge across the head and see what thicknesses of feeler gauges can be slipped underneath it.

If a skim is needed, it's not expensive. The last one I had done was £25 and that was on a Nissan CA18DET head. Some outfits will charge more for an XU head as it needs to be put in a special jig as there is no top surface parallel with the gasket surface to rest it on but most are used to XUD heads and it's the same jig for the 8V XU head.

The differing thickness of gaskets only apply to the XUD diesel. On a petrol, having a lower compression ratio, you can get away with quite a bit of skimming before encountering issues and the valves are a lot further away from the pistons.

Be careful to check another aspect of the head if it's been badly overheated. You need to check to see if the heat has annealed it. If it has, not only will it have warped but it will have shrunk too and the easiest way to determine this is to see if the cam caps are hard to remove due to binding on the studs and/or the head bolts bind in the head holes as they come out or the head gasket fire rings have left deep impressions in the head surface. If it is annealed, it's scrap. Ive seen one XUD head that showed signs of annealing and that one showed 30 'thou of warpage as well!!!

As long as the overheating was neither severe nor prolonged, you should get away with a light skim.

Luckily a head-job on a 1.8i 8V is a walk in the park relatively speaking. A day's work, easy

JamesQB · Post by **JamesQB** » 22 Mar 2009, 23:49

Thanks for the info. I've asked more about what happened and here it is: whilst out and about, they had someone bump into them on a roundabout and break off the front bumper, with no obvious damage to body or chassis. I'm not convinced that's related to what happened after - radiator's been leaking for ages. They continued driving the car a couple of miles to the shops, when they returned to the car, it was hard to start and when it did it was very lumpy and smoking from the exhaust (grey smoke apparently). The trip homeward bound was lumpy with the car jerking a lot, and as they neared home, they noticed the temp gauge was near maximum (near 100 degrees I think it was). They carried on in the hope it'd just go the few hundred yards to the house, but it died on them. When they lifted the bonnet, there was oil all over the place apparently. It wouldn't restart and still won't. There's oil in the water I'm told, although the oil that was everywhere when they first lifted the bonnet has more or less gone wherever oil goes. The coolant temp wasn't high when it was being driven to the shops, which makes me think the head gasket failed, lots of coolant ended up going into the cylinders, and so it dried up quickly and that's why it got so hot. I think that's most likely as they're very strict on filling it up before every trip and doing only short trips, and they'd got used to how much water it lost from the leaky rad during each trip out. The last journey shouldn't have seen the coolant become empty, it should have just lost a litre or so.

I'm currently trying to help talk my dad through removing the head, but it's not easy as I'm in the UK and he's in Spain, and getting on in years now, but he's got the Haynes manual to work by. He's managed to get the rocker cover off, and tomorrow will start on the next step. I'm going over in 3 weeks time and plan to take whatever spares are needed and help put it back together. Just got to buy an angle wrench addition that will fit onto my torque wrench, as I have never had one before or used one - never needed to angle tighten anything before on a car.

From all of this, do you think that the head is warped? Sounds like there's a lot wrong what with oil in the water and not starting (no compression I'd imagine), making it seem like gasket blown from cylinders to oil and water ports, so they're all mixing. Will be checking with ruler and feeler gauges anyway though, as suggested.

There is one thing I'm not sure about: the Haynes manual states that the head bolts must be thrown away under the section for the 2.0 litre engine, but for the 1.8l, it says nothing about throwing them away or re-using them. Are the 1.8l head bolts the stretch bolt type? It's £20 for a new set, and I think maybe it's best to use new just in case. The manual does give maximum bolt length measurement for re-use, but it also gives the measurements for the 2.0l engine ones even though the text says throw them! Would I be right in assuming that it's only stretch bolts which require angle-tightening?

Thanks again,
James

Deanxm · Post by **Deanxm** » 23 Mar 2009, 22:51

All the XU petrols are tde same, with the same heads, blocks (although bored to a different capacity) even the exhaust manifolds are the same between the 1.8 and 2.0.
They will both use stretch bolts for the head which is why you have to angle tighten them and i would not risk reusing the old ones, i always use new because as you say they are only £20.
One thing to watch, the original head bolts are female, torx heads and the cit replacements will be male so you will need torx style sockets, sorry i dont know the fancy name

.
I dont think the head would have warped myself but its always worth a check.
Dont forget, new water pump and tensioner while your doing it.

Good luck
D

JamesQB · Post by **JamesQB** » 24 Mar 2009, 01:29

Thanks for that. I'll have to look for the male torx sockets, might try ebay. If the head hasn't warped, though, wouldn't that mean the overheating hadn't caused the head gasket failure? If not, then I'm unsure what would cause it to fail as it has.

My dad's having a problem taking the camshaft cover off, and since I'm not there, I can't think what he means when he says that a "rod" is going into the right-hand side (as viewed from under bonnet) of the camshaft cover, and preventing that side of the cover from moving at all, let alone lifting up easily as the hayne's manual states. Any ideas what it could be?

Hadn't thought about the water pump and cam belt tensioner... really don't fancy the extra work when I'm over there if I end up fitting it all (most likely)... is it really, really important? Also looking at cost, can't help but think it's going to be too much money to warrant getting this car up and running again, especially with cost of new radiator on top. It's 40 quid just for head gasket and new bolts from euro car parts before anything else. Just hoping the head isn't warped. Haynes manual says only 0.05mm of warp allowed, that's the thinnest feeler on my set of gauges, thin as paper if not thinner!

Old-Guy · Post by **Old-Guy** » 24 Mar 2009, 13:36

James

Tell your Dad to undo the head bolts a bit at a a time in the same sequence as Haynes gives for tightening the head down. Otherwise there is a real risk of warping the head (even more). If you think about it, if you release all the tension on the bolts one at a time (and probably starting from one end), the head could be expected to curl up very slightly at the free end!

Make a really thorough job of cleaning both head faces; a small piece of thick hard plastic (Perspex) makes a good safe scraper that can be 're-sharpened' with a file.

It's essential to use new bolts - the whole point about angle tightening is that the high-tensile bolts are pre-tensioned (as incredibly strong springs) to keep the head tightly clamped to the block through thousands of cycles of expansion-and-contraction. Bolts on an over-heated engine are likely to be over-stretched by different amounts.

Oil in the water is common when a head gasket goes badly. The oil-way between block and head (that passes through the gasket) is under much higher pressure than the cooling system.

Here's a really horrible (but practical) idea: if the leak in the radiator is just some small nicks in the radiator tubes, repair with either Araldite rapid (aluminium) or solder (brass/copper). In my youth, I successfully soldered up a whole line of nicks in the vertical tubes of a TR2 radiator after hitting a stray dog at speed one dark wet night.

For TX sockets, I suggest you try a local independent motor factor (who may well sell a small kit with just the sizes used for head bolts) or Machine Mart.

On the question of "Is it worth it?", any replacement car is going to be an unknown quantity - I reckon a retired English couple in Spain would be at a huge disadvantage.

Best of luck

Guy

JamesQB · Post by **JamesQB** » 24 Mar 2009, 20:53

Some very good advice there, thanks for going to the trouble. I'll be phoning later to see how he progressed today. I've found out that he missed two bolts holding the camshaft cover down originally (before being stopped by the odd 'rod going into right-hand side of cover' problem stopping him yesterday), and that there's a crack in the camshaft cover now which he thinks he caused by trying to prise the cover off with the 2 bolts still in situ. I've tried breakers, cheap citroen spares places and ebay, but no joy finding one. I hate to think what a citroen dealer would charge for the whole camshaft cover. Seems to be going from bad to worse.

Old-Guy · Post by **Old-Guy** » 25 Mar 2009, 15:40

James

Forgot a very useful tip for most engines that have head bolts (as opposed to studs and nuts):
Cut the heads off a couple of the old bolts, file /grind off the sharp edges and saw a deep (about 5mm) 'screw-driver' slot into the cut end. Screw these headless bolts about halfway in diagonally opposite corners as temporary locating dowels for the head gasket while fitting the head. Fit the other bolts finger tight before removing the 'dowels'. The deep slot gives enough grip on a thin screwdriver blade to easily remove the dowels despite oily hands.

Repairs by remote control - been there, done that! Far too often (with PCs).

Best of luck

Guy

JamesQB · Post by **JamesQB** » 25 Mar 2009, 20:01

Another very handy tip that I'll put to use if it gets repaired. I've encountered something else though: the Haynes manual says two types of head bolts are used, either hex heads or Torx heads. When buying new ones, do I need to get ones with the same heads? I ask because the manual gives two very different tightening techniques, torques, and angle-tightening degrees depending on which are being used. When checking GFS for head bolts, they list one lot with no mention of whether hex or Torx...

Deanxm · Post by **Deanxm** » 25 Mar 2009, 20:07

Im sure all cit do now is the Torx type headbolts i dont think the hex ones are available anymore, i certainly havent seen them available anywhere.It wont make any difference which you use though so long as you follow the haynes jokebook.

D