Coolant Leak But No Overheat

[KJS]

Hi what would happen if the car has been run without coolant but the temperature meter (the one next to fuel meter) works like usual?

these are the things:

1) the temperature meter works like the same as when there's coolant in radiator.

takes 5 minutes for cold start to move the needle and 7 minutes to warm up

2) when realise the coolant leak and coolant is dried/gone, why the time for the car to warm up remains the same?

whenever the car is warmed and driving, it reaches half of the temp meter (with or without coolant)

but isn't it when there's no coolant the engine will become overheat and the needle will move up more than half of the meter?

what possible damage has been done to the car or engine? (it has been run for 600kms after last coolant flush during service

throughout these 600kms the car takes the same time to warm up like before

there's no indication that the engine is overheat judging from the temp meter (or was there?) because the needle never moves up more than half

is the coolant temperature sensor faulty?

fyi the coolant leak is between the coolant bottle on the driver side engine bay and the radiator, i am guessing the hose wasn't tightened but will send to mechanic tomorrow since he was the one who last serviced my car

[Adriano]

Coolant temp sensors dont register overheating if there is no coolant.

[KJS]

I used a demineralised water to filled up both the coolant tank and radiator (pour from the radiator cap)

it took about 1.25L for the tank to reach max level and top of radiator.

do you think throughout this 600kms+ drive the engine has been damaged?

[Adriano]

No, 1.25 isnt too bad, not the best though.

[JonnoHR31]

sounds like just your overflow was empty? what level was the radiator at? aslong as it had atleast a couple litres in there the gauge should be accurate

[KJS]

hmm the coolant tank on the driver side (left side of engine bay if you stand in front) was empty

coolant was low but didn't know how low

then I refilled with demineralised water on both the tank and the radiator both took 1.25L

I guess if you say as long as there's a few L there gauge should accurate, means the water temp meter is working fine and so as the coolant sensor

I was thinking if there's less coolant needed to be heated, why the required time to warm the engine is the same compare to the past (when there wasn't leak)

I also checked the engine oil and it remains at H

[neo32]

the sensor is at teh top of engin most likely where the air will be

its hard to mesure water tem p if theres no water around the sensor

[KJS]

it's strange, there's no leak ....

and the mech put 1 bar pressure on top of the radiator and it holds the pressure

he said everything is tightened

[s13_Skyline_inside]

it takes way more than 1.25 ltrs into the rad so id say you havnt lost all the coolant

[KJS]

Hi the coolant level has ocassionally gone down a bit.

During very cold weather, ocassionally (I mean it doesn't usually happen but sometimes it just happen), when the car is started and the weather is cold (eg in the late night or early morning), there's white smoke coming off. However when you drive away, the smoke is gone.

to describe it more detail, it only happens during warm up.

process: start car, no smoke, after a while waiting for car to get warm, then smoke, drive away, smoke is gone.

Mech has put 1bar pressure on the radiator cap and it holds the pressure, so he said it is fine and gasket has no problem.

The thing is, why only cold start? and it does not happen when car drives away or in later start.

is my gasket fine?

I would say the level of coolant in radiator remains high to the top but the level of coolant in the tank on driver side has gone down a little.

hose is tight, cat converter is fine (was checked few days ago), engine oil level is fine.

so what is the problem?

also the coolant has no discolouration (remains green after top up with demineralised water)

Edited July 4, 2009 by KJS

[GT-RZ]

Wouldn't worry too much. If your coolant is overheating too much you will know when your bay sounds like it's got a kettle in there...

Look on the floor where you park your car. is there any coolant on the floor?

[KJS]

no there's no coolant leak on the floor.

now I am only worry about:

is my engine burning coolant? why ocassionaly there's smoke during cold start (I don't think it is condensation because the coolant level in tank has decreased a bit, maybe 1-2cm from the max but radiator only drop a tiny bit), and yes I top up the coolant to check this and only manage to discover the slightly lower volume after seeing smoke happen

also when I started the car, the coolant in the radiator didn't have bubbles or the coolant amount didn't drop (of course that time also didn't have white smoke)

so it does not always happen, it happen ocassionally

you reckon I don't need to worry? I just feel worry because I am afraid a hidden problem might be there just that I don't know.

[GT-RZ]

when you start your car on a cold day you will always get condensation, it will not lower your coolant level... smoke is smoke and condensation is condensation... can you smell smoke?? is it white or disappears?

plus when you first start your car there is no way it would overheat straight away.

From what you have explained it sounds like condensation on a cold day. unless you can explain in more detail i don't think you need worry.

[KJS]

at first I thought it is condensation, because of the cold weather.

but the smoke is a bit too much and the wind will blow to the front passenger screen

however the thing is, I cannot define it as blown gasket because when I starts driving the car, the smoke will be totally gone.

and most the time it will not happen again in next start up, or even next cold start

it happens occasionally

sometimes even if the night is cold, it doesn't happen

the unpredictable manner makes me think this is worth to be worried.

if the cold night has smoke, next morning when I check the coolant level of the tank on left side (driver side), it is lower than the H level

but when I open the radiator cap, it is still full or maybe insignificant drop.

now I am not worried about whether the engine has been overheated

but I am wondering why the coolant level has dropped

I mean randomly dropped

and random white smoke

[bozodos]

can't you use normal tap water to put into your radiator?

[GT-RZ]

can't you use normal tap water to put into your radiator?

Is that directed at his question or is that your question You wouldn't want to leave tap water in there for any other reason than flushing it imo... unless you want rusty water chambers.

[brent32]

I think you should see small bubbles coming through the radiator(with radiator cap removed) when you repeatedly crank an engine with a blown head gasket. Is this true, maybe im wrong?

EDIT: just thought about it and this is a trick used in darwin where some cars have themostats removed. ie probably wont work if thermostat is closed.

also i recently had a radiator leak and the first radiator pressure test conducted by a workshop that specializes in radiator repair *apparently* held pressure even though coolant had literally drained from the stationary car. I told them to do it again and then they found it had a crack. They never charged me for the test and I took my radiator elsewhere to be fixed.

Edited July 6, 2009 by brent32

[bozodos]

I'd been told that if there was some coolant already in there, then using plain old water wouldn't adversely affect it for a top up? I was hesitant to do that to mine for fear that it would corrode the insides of the radiator.

[GT-RZ]

I'd been told that if there was some coolant already in there, then using plain old water wouldn't adversely affect it for a top up? I was hesitant to do that to mine for fear that it would corrode the insides of the radiator.

No not too bad if it's got coolant in there your just diluting it. allthough it's better to top up with demineralised water rather than tap water. obvious reasons.

[mark33gtst]

Tap water is fine for top ups.. Looks to me like you just had an air pocket in your coolant system.. Not bled properly when the coolant was changed... Don't stress unless it drops another liter...