Loosing Coolant but not overheating

I appear to be loosing coolant from somewhere on my 1995 P38 4.0. I fill the expansion tank up to the level and it drops down to pretty much near the bottom and eventually it empties. It's not overheating though no matter how low it appears to get.

Some things I've checked/replaced are:
Replaced the expansion tank cap
Checked all the spark plugs to make sure none are cleaned/different from the rest and they're all the same.
Checked most of the hoses going from the expansion tank/to radiator/to engine.
Carpets aren't wet on the inside.
Expansion tank doesn't seem to smell of exhaust gas.

I've got a ticking noise that you can hear when you increase the revs which sounds like its the manifold but I don't think it's anything to do with that, just letting you know.

I've also noticed that you can see steam/smoke coming from the exhaust no matter how hot the engine is or what the outside temperature is. It's not excessive just a small amount, might just be normal but I wouldn't know.

What else should I be checking to narrow this down?

Thanks,
Jack

Water pump leak from the shaft seal?

Datatek said:

Water pump leak from the shaft seal?

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I've just had that on the L322...emptied about 3.5 litres in little over a mile....no overheat (thankfully)...thought you would notice steam (as I did)...but then again it depends on how bad the leak is....

Mine went suddenly and as such was quite spectacular when it did with the amount of steam it had produced....

If yours is weeping, that could be the cause....see if you can find traces of dried coolant sprayed on the bonnet underside, the fan, the pulley, the timing cover etc....

Datatek said:

Water pump leak from the shaft seal?

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How would I go about checking this? Just look for water leaking from the pump?

Saint.V8 said:

I've just had that on the L322...emptied about 3.5 litres in little over a mile....no overheat (thankfully)...thought you would notice steam (as I did)...but then again it depends on how bad the leak is....

Mine went suddenly and as such was quite spectacular when it did with the amount of steam it had produced....

If yours is weeping, that could be the cause....see if you can find traces of dried coolant sprayed on the bonnet underside, the fan, the pulley, the timing cover etc....

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I'll have a look at that later, but no I'm not getting any steam or anything at all, it's pretty much running normally apart from loosing a bit of water each time.

It always seems to drop to around the same level each time though if thats any help.

jacckk said:

How would I go about checking this? Just look for water leaking from the pump?



I'll have a look at that later, but no I'm not getting any steam or anything at all, it's pretty much running normally apart from loosing a bit of water each time.

It always seems to drop to around the same level each time though if thats any help.

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There is a weep hole on the bottom of the pump from which you'll see water dripping. Sometime leaks are small enough and out of sight and are hard to find because the heat of the engine condenses or evaporates the coolant before it can drip to the ground making it's location apparent.

Ok it is winter and you are using your heater. Fill expansion tank all the way up( past full mark) and see what happens. Could be your heater core or heater hoses dripping a bit. check your carpet under you heater is it wet?

check you water pump, there is a very small hole in the water pump casting on the underside, get a light in with the engine running and see if you can see it dripping, normal they leak and the fan blows the water everywhere

poloracer877 said:

check you water pump, there is a very small hole in the water pump casting on the underside, get a light in with the engine running and see if you can see it dripping, normal they leak and the fan blows the water everywhere

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Second that, it's quite common unfortunately

I've just checked the water pump and I can't see anything leaking or dripping from anywhere near it. It looks fairly new actually, the previous owner might have replaced it recently or something.

I've rechecked all the pipes and I can't see anything at all leaking.

As coolant evapourates, it usually leaves a white stain....

Leaks are not always evident as it evaps and dries quickly....leaving no trace apart from a faint white stain....

I, like the others, am inclined to suspect the water pump...take a gander as I mentioned above for any evidence of spray marks thrown about by the fan or pulley.

You can buy a coolant dye that you add to the coolant and will help to show up a small leak. If you access to a UV light source then you can buy UV dye and it will glow under a UV light.

Mine was doing this and it did turn out to be the o rings. I'd double check to be sure.

mine was the same. 4.0se. the levels been dropping very slowly since i got it. small amount of steam from the exhaust and i wasn't sure if it was normal or that my head gaskets were on the way out. anyway, went for a small drive today and the water pump bearing totally collapsed and left me stranded. i've looked before and couldn't see any leaks.

Have you got a head gasket tester, you put it in the top of the expansion bottle and put blue fluid in it, if it turns yellow there is exhaust gas in the water, if the car is on gas the engine is well known for a leaking liner, of you remove the plugs you should be able to see one piston that looks like New, ie steam cleaned

poloracer877 said:

Have you got a head gasket tester, you put it in the top of the expansion bottle and put blue fluid in it, if it turns yellow there is exhaust gas in the water, if the car is on gas the engine is well known for a leaking liner, of you remove the plugs you should be able to see one piston that looks like New, ie steam cleaned

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I haven't checked the pistons, but I've checked the spark plugs and none of them are cleaned.

jacckk said:

I haven't checked the pistons, but I've checked the spark plugs and none of them are cleaned.

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are they green color? or bronze looking

Thor1950 said:

are they green color? or bronze looking

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I don't think so, they were just generally a bit black from the carbon build up.

Use the car, and leave it until the next morning and see if you can put your finger on the hole in water pump casting any wet at all even a tiny bit and it is leaking, if a liner is leaking if you look under the bonnet at night, as dark as possible, look round the spark plugs, you might be able to see glowing from the thread holes, with the engine running

I had the same problem.. and found out that my heater was leaking and radiator. The radiator leaked at the top, where is the plastic part of radiator on which hoses go on. Plastic did break in straight line about 5cm long, probably because of the age of it. I had a little steam leaking but barely visible, then i squized the hoses and saw bubles going through the plastic bit of radiator. I hope that you will understand my post, because of my bed english

nejc003 said:

I had the same problem.. and found out that my heater was leaking and radiator. The radiator leaked at the top, where is the plastic part of radiator on which hoses go on. Plastic did break in straight line about 5cm long, probably because of the age of it. I had a little steam leaking but barely visible, then i squized the hoses and saw bubles going through the plastic bit of radiator. I hope that you will understand my post, because of my bed english

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Don't worry it's a lot better than some of the English on here can manage.