Peugeot 405 1.9TD losing water

I have a high mileage 405, 1.9TD. Recently, I noticed steam coming from the offside front of the car, although the temperature guage read normal. I had been driving for around 20 mins on a dual carriageway when I hit slow moving traffic and noticed the steam after a few minutes. I called out the AA, who diagnosed a stuck thermostat. However, I have now replaced it but still have the problem. After driving the car and then stopping the engine, I can see a slight amount of water bubbling out of the radiator cap. As it runs down the expation bottle, it hits the hot radiator and then steams off. I think that this was the cause of the original steam I noticed in the traffic jam. Additionally, after the engine has cooled, there is still some (but not much) pressure in the cooling system and, upon removing the radiator cap, a small amount of water is occasionally lost on releasing the pressure. Why would I be losing water through the radiator cap? It is not a great amount-about 1 pint a week (300miles). Could it be the head gasket? My car has otherwise had 224k trouble free miles!

Reply to
Istherestillhope
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radiator

Could just be that the rubber seal inside the radiator cap has perished, try putting a new one in and see if it stops leaking. I've seen a thread somewhere on here which said you can even make a perfectly good one out of an old bike inner tube, if you are so inclined.

HTH Andy J

Reply to
stealthf0x

"Istherestillhope" wrote: > I have a high mileage 405, 1.9TD. Recently, I noticed steam > coming from the > offside front of the car, although the temperature guage read > normal. I had > been driving for around 20 mins on a dual carriageway when I > hit slow > moving traffic and noticed the steam after a few minutes. I > called out the > AA, who diagnosed a stuck thermostat. However, I have now > replaced it but > still have the problem. > After driving the car and then stopping the engine, I can see > a slight > amount of water bubbling out of the radiator cap. As it runs > down the > expation bottle, it hits the hot radiator and then steams off. > I think > that this was the cause of the original steam I noticed in the > traffic > jam. Additionally, after the engine has cooled, there is still > some (but > not much) pressure in the cooling system and, upon removing > the radiator > cap, a small amount of water is occasionally lost on releasing > the > pressure. > Why would I be losing water through the radiator cap? It is > not a great > amount-about 1 pint a week (300miles). Could it be the head > gasket? My car > has otherwise had 224k trouble free miles!

When the last engine on my 205 Diesel started dying it messed up the water pressure. This caused the expansion tank to overflow and the radiator to bust spectacularly in about 20 places eventually. I tried measures to stop it, like Halford radiator sealant but it just kept springing more leaks.

Previous to this the coolant would need topping up every few months, something you don?t have to do on a healthy Diesel.

Eventually the engine stopped starting properly without being rocked and when the engine was inspected three days after the beginning of the starting problems, flecks of Metal were in the emulsified oil.

I don?t know if you can do this on the 405 but to check the health of a 205 diesel (which has an almost identical engine) you take the cap off the expansion tank and start the engine. If vapour (exhaust) comes out of the coolant then you have damage in your engine (cracks, warped gaskets etc).

Personally if this test proves true, I?d book the engine in for replacement with a reconditioned unit, or get yours rebuilt.

Reply to
Streltsky

Many thanks for your replies.

I have tried replacing the radiator cap which reduces the water loss considerably. I have also found that after running the car for about 20 miles to work, when I return to the car some 8 hours later and remove the radiator cap, water is forced out under pressure even though the engine is obviously cold by this time.

I have also tried running the engine with the radiator cap off and water level to the max mark, no vapour comes out but, after a short time, the water overflows the filler cap.

Has anyone any further ideas or does this confirm a head gasket problem?

Many thanks,

Clive.

Reply to
Istherestillhope

If its a head gasket problem there will probably be oil in the cooling system.

JG

Reply to
Jim Goad via CarKB.com

I have a 1992 405 1.8TD and I lose water too, maybe a cupful every few hundred miles and this has been going on for 40,000 miles. I would first suspect the radiator cap and fix that. Second I've noticed that if I fill the rad only to the marker deep inside I lose less water - there is a little hole in the side of the rad neck just below the rad cap which I take to be some sort of pressure regulator - too much water and water flows out here. Sound familiar? Third (which may not apply in your case) I'd check the pressure filer hole on the off-side of the rad. This has an o-ring which hardens and leaks after many years. Fourth I'd check the joint by the side of the heater matrix under the glove box ... this has two o-rings and also leaks - if a lot it's wet carpets, but if a little is just mists the inside of the windows and smells of anti-freeze. Only then would I seriously worry about head gasket, and only if losing a lot of water. A search here will show it's a common worry, and it happened on my previous petrol 405 estate as well. It's something I just learned to live with. Cheers,

Istherestillh> I have a high mileage 405, 1.9TD. Recently, I noticed steam coming from the

Reply to
Wichita

Reply to
MICHAEL ROCHE

Thanks again for your ideas. I don't get any noticable oil in the water. I have tried draining some coolant into a container but cannot see a film or rainbow effect in the water. I had been losing a minimal amount of water for years - I had to top up every 4000 miles or so, certainly nothing to worry about. There is no dampness, anti-freeze smell or misting up inside the car. I have noticed that, since fitting a new radiator cap, I lose less water, but after the engine cools, the cooling system remains under pressure. If I release this pressure using the 2 vents, on the radiator and the small hose near the thermostat (air escapes from both), I can then remove the radiator cap to see the water level right up to the brim of the expansion bottle filler neck, even though I had not originally filled it to this extent. (If I do not release the pressure prior to removing the radiator cap, I get covered in coolant). I therefore assume that there is now air in the system which is displacing the water, giving the appearance that the radiator has filled up whilst I have been driving! Many thanks for your help and advice so far. Clive.

Reply to
Istherestillhope

The french in there infinate wisdom built the 405 with dodgy coolant system. There are parts of the coolant system that are higher then the radiator filler hole When you fill your car up you have to make sure you use a header tank and bleed the system carefully. Failure to use a header tank and bleed properly will lead to air locks and these airlock can destroy the engine. I am also led to believe they can give symptoms you describe. Never encounted my them myself but i always use a header to refill. Have a look on

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use it and there is loads of hints/ tips and how to's on bleeding the405 engines plus more. hth si

Reply to
caveman_si

Thanks, Caveman. My system has a bleed valve at the highest visible point of the cooling system, which I always use when I refil the rad. What is suspicious is that every time the engine cools, I loosen that bleed valve and, without exception, air is always released prior to water being expelled. In other words, it seems to me that air is being sucked or forced into the cooling system every time I drive and accumulates at the highest point (obviously) until I release it again. I have had a suggestion that the block or head may be cracked. Is this likely, given the symptoms? Thanks again for all your help, Clive.

Reply to
Istherestillhope

Hi again! I've visited the site Caveman suggested - it does certainly cover a lot of topics. I saw mentioned on there about a compression test. I know how to do this on a petrol engine but a diesel has no spark plugs to give access to a compression tester. I can only think that the glow plugs would be removed instead but, they are in such an awkward position that getting to them is an art in itself, let alone attaching a compression tester to the vacant hole. Does anybody know how to compression test a Peugeot 405 1.9 turbo diesel engine? Thanks, Clive.

Reply to
Istherestillhope

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