ZX coolant loss...

[RussellF97]

Hi All,

I have a 1995 1.9 non-turbo diesel ZX, 136500 miles.. The little devil's started losing coolant fairly rapidly - up to a litre every 10-15 miles!
I don't drive like a looney; I live in the middle of Brittany and virtually the only trips I do are the 14 mile round trip to the local town to go shopping.
There's no wet carpets, and no sign of leaks in the engine compartment. This afternoon I topped up the system and fast-idled the engine until the fans cut in - no sign of any moisture from the exhaust and no bulging rock-hard rad hoses.
There's no mayo in the oil - I saw an Audi once where the sandwich block had become porous and that gunged the whole engine up big time!I was impressed.
I can't smell anything odd on the coolant either (I was an AA Patrol for twenty years and coolant would invariably smell weird if the head gasket was gone), so I'm at something of a loss here. Does anyone have any ideas?

I await any replies with interest!

Cheers,

Phil

[citronut]

these engines dont offten get mayo in the oil, they usualy presurise the coolant system and push the coolant out of the cap

i know you say you cant see any leeks under the bonnet but maybe the water pump is leaking as it is sometimes difficult to spot,
or the other points that leak are the rubber blancking caps at the water branch on the rear of the block behind the water pump,perish and split,
or the bottom hose were it gets soaked in oil at the engine end,

regards malcolm

[RussellF97]

citronut: many thanks for that.
I've done a bit more testing and it would appear to be the head gasket, so it's head off time... Deep joy...

[spider]

Nice and straightforward on the NA unit as no (awkward, well it was when I realised the inlet had to come off (again!) as I did not put it back first) oil feed pipe.

The only things I don't like about the XUD gaskets are the lack of block dowels, holding a fully built head by hand and trying to not drop it is difficult for me at least, although I have a couple of cut down old bolts to act as temporary guides now. The centralising pin affair on the 1.9's is not usually too much trouble either. Only ever seen two with a seized plunger (one was mine) and removing the mounting and a hole / soak overnight and refit cured.

At least its an easy one

[jgra1]

what's that pin spider?

[RussellF97]

jgra1: that would be my question as well.

spider: could you elaborate on "The centralising pin affair on the 1.9's is not usually too much trouble either. Only ever seen two with a seized plunger (one was mine) and removing the mounting and a hole / soak overnight and refit cured" please.
There doesn't seem to be any mention of whatever it is in the Haynes book I have...

[spider]

The plunger is just the tensioner plunger, it is rare for it to seize though so don't worry about that. I only ever saw two seized ones in about 11 years.

Not sure if they all have the central pin, its on the timing belt side. You may need to just use a spacer / bolt / washer affair to remove it. The 1.8'd don't have one. I tried to find a pic via Google but could not, I suspect some members here may have a pic to hand.

I think Haynes mentions it but I don't have a manual to hand to check.

[RussellF97]

spider: Thanks for that. It's the timing belt tensioner; yes? There should have been a new one fitted when I had the belt done about 38,000 miles ago but having seen the damage that can be caused when belts go over their time, I'll be fitting a complete kit.

[spider]

One of the locating fittings for the tensioner is a stud yes.

If you replace the tensioner roller (not really needed, only ever done two iirc, they are made from decent metal unlike not ideal plastic stuff you find these days) you'd need a holding tool or a bit of patience to re-assemble the plunger / spring etc. Its not bad actually, no where near as bad as its described.

[RussellF97]

spider: thanks for getting back to me on that. I'm a bit of a Citroen virgin, only ever having owend Minis previously (the real ones not the BMW upstarts) so to go from playing with 1950's-vintage petrol fuelled, iron-headed OHV stuff to 1990's aluminium-headed OHC, heavy oil engined beasties with timing belts is a bit of a step change: any vehicles I played with while I was with the AA belonged to someone else so don't count!
To be fair to the ZX, it went through the Controle Technique (the French MOT) in November with no probs and the most expensive things I've fitted to it so far was a set of Michelin Energy Saver tyres (which probably doubled the value of the car!).
I find it comfortable, reasonably quiet and economical and it has a heater that demists the screen in less than half an hour (unlike the Mini), so I would like to keep it going as long as possible.
Still, the head comes off tomorrow - we shall see what we shall see...........

[spider]

The XUD unit is extremely tough and durable and capable of starship mileages as others will attest to I'm sure. Being what was a late 70's design its made from proper metal too aka tensioners etc. Alum head though.

Most headgasket problem seem to occur due to overheating (warp head / headgasket) or coolant change neglect (unfortunately common among owners) as older coolant + rust in coolant will eat the headgasket away. This may also be the overheating issue in some cases too, ie: poor quality coolant / clogged pipes = lack of cooling effect as you know.

I did mine at the roadside , no garage or driveway here, took a few afternoons work not bad at all. Did not even have to jack it up either (but I'm small) , jack only needed as engine mounting needs to come off for timing belt / head. The front right (well right when sat in the car, OSF one) only really, the rear you can leave in most cases despite what repair manuals say.

[citronut]

the other cause of gasket faliure is the cooling fan not cutting in as it should,

regards malcolm

[RussellF97]

citronut: thanks for that, but the fans do cut in at an indicated 95 degrees as advertised. They must draw quite a bit of current, on tickover the engine slows down quite considerably!

[Lighty]

just remember that there are different head gasket thickness's, its best to match up with the origional unless you are skimming the head, which you really ought too.

[jgra1]

ah that old git plunger .. yes its tricky holding that back in while working alone..

this one?


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