gen3 newbie question: how to top up/check coolant

[Sydneycamry]

Hi there sorry for creating a new thread on something that should be general knowledge. But i'm quite confused now.

I have a 4 cyl 3sfe engined camry. I've read on websites that you should check coolant levels when the engine is cold, and that you should add coolant up to the 'full mark' when the engine is cold.

However, i also read today that when the engine is warm/hot the coolant level in the reservoir should be at high, and when cold it should be at low.

A friend has borrowed my car and I am unsure whether the camry has a 'high' or 'low' mark or a 'full' or 'low' mark on the reservoir tank. That should make a big difference.

So what i've been doing since i've owned the car is to check the coolant when the engine is cold and top it up until the 'full' mark, if there is one. Is that wrong?

What is the correct way for a gen 3 camry?

Appreciate any advice.

[AliRazoR]

you are right

[71Corolla]

FYI, after doing some research I learned that water will expand 4% going from just before the freezing point to the boiling point. Coolant, which is 50% water, will show a similar expansion. From about room temperature to the boiling point, expect about a 3% expansion (it starts to expand at a non linear rate as the temperature goes up).

So that explains why your overflow tank level changes from a cold to a warm engine. The owners manual does say to fill the tank to the top line when the engine is cold, and does say it is normal for the level to change. But that doesn't explain why on my '93 Camry (soon to be sold ), the level stays exactly the same, warm or cold, but on my other two cars the level does change.

Anyone know why?

edit - also of note, because of what is known as an isochoric process, the larger the capacity of the cooling system, the more the level in the overflow tank will change, assuming the tank is approximately the same size on the various cars (the Toyota ones are all similar).

[Sydneycamry]

Originally Posted by 71Corolla

FYI, after doing some research I learned that water will expand 4% going from just before the freezing point to the boiling point. Coolant, which is 50% water, will show a similar expansion. From about room temperature to the boiling point, expect about a 3% expansion (it starts to expand at a non linear rate as the temperature goes up).

So that explains why your overflow tank level changes from a cold to a warm engine. The owners manual does say to fill the tank to the top line when the engine is cold, and does say it is normal for the level to change. But that doesn't explain why on my '93 Camry (soon to be sold ), the level stays exactly the same, warm or cold, but on my other two cars the level does change.

Anyone know why?

edit - also of note, because of what is known as an isochoric process, the larger the capacity of the cooling system, the more the level in the overflow tank will change, assuming the tank is approximately the same size on the various cars (the Toyota ones are all similar).

Thanks to both of you for confirming that i have been doing it correctly.

Almost every three days the coolant level falls below the minimum level so i'm loosing coolant somewhere. I've seen puddles after the cars been turned off for an hour or more just underneath the res. tank. Anyone else experienced this? Also there seems to be TINY floating white bits in the coolant res tank. Its like hardened teeth tartar early signs of blown head from little oil and coolant mixing together?

[AliRazoR]

Originally Posted by 71Corolla

F the level stays exactly the same, warm or cold, but on my other two cars the level does change.

Anyone know why?

I think your radiator cap is not working properly.

http://auto.howstuffworks.com/cooling-system7.htm

[71Corolla]

Originally Posted by AliRazoR

I think your radiator cap is not working properly.

It is, and is a brand new cap from the dealer. The cooling system works flawlessly, no coolant loss, and the coolant is right to the top of rad when the engine is cold. The level must change but I can't seem to observe it.