Hi again. I was reading on some site:
http://www.honestjohn.co.uk/carbycar/index.htm?md=95 (towards bottom of bad points) about head gasket can go from sludge build up from corroded radiator and heater matrix.

Just wanted to know how to check this, as my radiator has a slight leak I've been unable to find anywhere. (very slow leak).
Also i get a built up of oil around the filler cap which then sludges and for it to come up from there surely there must be some pressure on the oil? which would be caused by sludge blockages? the car has had the head gasket replaced 14k miles ago also as it went on the owner before me.

I don't know terribly much about cars and anything i do know I've basically taught myself so go easy if I'm sounding like a fool (happens alot)
Thanks

The coolant leak is probably not the cylinder head as they dont usually do things in subtle ways. Once the head gasket goes you'll know. Sludge in the oil filler cap is usually water that has condensed and emulsified with the oil. Every litre of petrol burnt creates a litre of water (plus carbon dioxide). Lots of shart runs are bad for the engine. It needs a proper run every week to get it hot and healthy. If in any doubt get the cooling system flushed and filled with proper coolant. Apart from freezing, plain water causes corrosion and sludge. Tap water can be especially nasty. Only use distilled water (such as from a dehumidifier tank). The snag is that any holes blocked by sludge can spring into leaks - what is now a small rad leak, could soon show itself. You could chuck in some Radweld and hope. But coolant sludge will damage the engine. It leads to hot spots that stress the head gasket. Saving money now will be the most expensive option in the long run.

Well I'm going to flush the oil to change the oil filter anyway, so i might just flush the coolant aswell. Also i suppose me filling her up with tap water the other day isn't good ( i ran out of anti-freeze).
I was only really asking because i suspect that there's pressure in the oil somewhere and the head gasket has gone before on the car so it could go again if it's that causing it. Head gasket is fine atm though. Also instead of radweld i was told egg white works just as well and its much cheaper!

Egg whites might be ok in a Moggie Minor or Model T. Tap water is ok in an emergency but it should be flushed out ASAP. Radweld is also only an emergency fix and you risk clogging the radiator especially if its already clogged by corrosion. The only option is a proper rad flush and refill with distilled water and proper coolant or premixed coolant. If it leaks worse you'll know what has to be fixed. Leaks never heal up so better to get it found and fixed.

WhiteSei said:

Leaks never heal up so better to get it found and fixed.

Click to expand...

I would agree to this but I fixed my radiator leak with 'barrs' which you break up (looks like oxo cube but tastes better) & let it circulate. That was over 2 years ago & not had to top up my mk2 punto radiator since. However yes I agree it should be replaced....when I find a cheap one on ebay

If the radiator is pinholed rather than corroded a self tapping screw of appropriate size works perfectly.

Cheers

SPD

Core plug coolant leaks are a pain in the rear to spot, but that might be where your phantom leak is, also the very edges of the radiator may be leaking very slowly, i've also seen leaks out of the thermostat gasket, so plenty of places to get looking!

I've used various internal leak sealers and all's been ok, but the systems had always had proper coolant so the corrosion was largely external. I'm always a bit more bothered when things are potentially furred up inside.

My GF's Focus 1.6 started leaking from the water pump gasket. Rad weld stopped it for about 2 months when the car was due for a service & she had the funds to do the job.

Oh, fun. Well I'm going to flush it out completely today, i noticed it's white around the back bleed valve so could be coming out of there slightly. Seemed tight on though. Ill see ho much crap comes out when i flush it anyway and decide on replacing iit if its too bad! Thanks

I've flushed the oil, i was planning on flushing the coolant in next few days but my leak has suddenly gotten much worse. Can't find where it's coming from still. Head gasket seems fine. Had no symptoms. So i was wondering where and what are core plugs? (someone mentioned them) and could it be the heater matrix? Or would that be noticeable. There just doesn't seem to be anything dripping from the car or anywhere i can see inside following all the pipes

Core plugs are the circular covers in the engine block that seal up metal casting holes in the water galleries. You need to get a close look with a small mirror.

Flush the cooling system and the leak will soon be obvious. Flushing the oil is a good idea but it wont help you find a cooling related problem.

Use premisxed coolant or distilled water and concentrate. Avoid tap water its too corrosive.

i know the oil won't help the leak but i was doing it anyway! BUTT!!!! after half an hour searching me n my uncle found the leak! was coming from the cylinder head by the head gasket but near the back, so it was evapourating before we could see it wet anywhere. Just been and got a new car! after my love of saxos for so long and chance to get a new car! I came home with.............. dun dun dun

A Pale blue W reg punto!

Btw the car is a 1.2 standard model, w reg 5 door. Is it supposed to have central locking as standard? I thought it did but it doesn't work if so.
Also is it hard for me to convert it to central locking using my old punto? I'm keeping it for parts

If you are going to drain the coolant system, you may as well fix that radiator properly. Brand new ones from the likes of Advanced Radiators can be had (and delivered) for less than £30. I toyed with the idea of radiator sealants but after reading a mixed-bag of success, I decided the extra expense and little extra hassle of a new radiator was worth it. Such a nice, efficient little radiator that the fan barely gets to have a whirr.

The radiator is fine :s
I mentioned few posts ago it's the cylinder head that's leaking so i went and got a new car yesterday, although I'm deciding if to sell or keep for parts with the old one.

My mother’s VW Golf had a water leak we couldn’t find. It turned out to be the back of the cylinder head, but the actual cylinders and oilways were all fine. Barrs Leaks / Rad Weld /whatever fixed the problem and it went on for at least another 20,000 until she sold it.

Change the coolant and add some of the above. At about £5 - it could be the cheapest head job ever.

Hmm, I might just try that.
As the leak has stopped now she's not being used. the leak also slowed the last day of me using her.
So going back over it, it started the same night after me and a friend flushed the oil.
We had wrong size allen key (only realised after putting engine flush in) so drove round the corner to get one. Did get quite hot! No warning light though. So could have warped the cylinder head ever so slightly!

BUT! the sump plug was tight in there! i gave up but my friend was yanking at it so maybe he jolted the engine abit too hard and loosened it abit, as it was the side opposite where he was pulling ( the side he would have been pulling downward) So it may have been that that caused it to leak. Hopefully some radweld will fix it then. Although there was a slight leak before hand that was coming from the same place it would seem. I think we just made it worse.