Silly Question !

[RIVERKARA]

Where should I be checking my coolant level ? I have had my beast for 4 years and have always checked it at the metal cap at the top ( i'm sure there's a technical term for it !!). my local garage said the other day that I should leave that alone and check it at in the plastic overflow bottle and top it up there. Please help !

[stormforce]

Where should I be checking my coolant level ? I have had my beast for 4 years and have always checked it at the metal cap at the top ( i'm sure there's a technical term for it !!). my local garage said the other day that I should leave that alone and check it at in the plastic overflow bottle and top it up there. Please help !

check the coolant at the rad cap where you have been checking it and evry so often just make sure the exspansion bottle has about 1/3 of water in it.
Not being funny mate but your garage needs to learn about what an exspansion bottle does

[Woodzie]

I always check at the rad cap like yourself .

[Slugsie]

As I understand it, check and fill from the rad cap as you have been doing. When the engine is cold, you want about 1/3 full, when it's hot, it will be higher. Just be very careful opening bits of the coolant system when it's hot, it can get lively.

[Karma Supra]

Expansion bottle should be fine, due to the way that the system works... Unless the system is not presurising properly, the expansion tank level will go down before the rad level does!

[Tallyman]

Only time you would ever check cooland level in the expansion bottle is if the expansion bottle has a pressurised cap on it (e.g. Vauxhall Corsa 1.7D). If the expansion bottle just has a cover cap then it's open to atmosphere and unpressurised and should, as previously mentioned, just be checked to make sure the pipe is covered. You are doing the right thing. Also, find another garage!

[TonyN]

Also, find another garage!

True.

[NiftyNev]

I've said it before and will say it again just for those who bother to listen. If the cooling system is operating as it should then there is no reason to remove the radiator cap. If the level in the expansion tank remains constant then you do not have a problem, will not be loosing coolant and will not need to check via the radiator cap. If you need to top up the expansion tank any more than a few m/l over a period of months then you need to start checking things, otherwise leave the cap on.

I remove my radiator cap about once or twice a year just to inspect the cap and for no other reason. My cooling system has only required about 200 m/l in about 2 years and that went in the expansion tank.

Nev

[NiftyNev]

Expansion bottle should be fine, due to the way that the system works... Unless the system is not presurising properly, the expansion tank level will go down before the rad level does!

Not quite. Radiater level can and will drop before the expansion tank if there is a leak in the system. More than the normal amount of coolant fom expansion tank will then be drawn back into the cooling system as it cools. This would then drop the level below normal and be an obvious sign of problems.

Nev

[NiftyNev]

If the expansion bottle just has a cover cap then it's open to atmosphere and unpressurised

Wrong. It is pressurised by atmospheric pressure. Think about how the system works.

Nev

[NiftyNev]

Not being funny mate but your garage needs to learn about what an exspansion bottle does

I think the guys at his garage do know what it does and how it works.

Nev

[NiftyNev]

I'm now going to put my flack jacket on.

Nev

[nero279]

Sod it - check both, it only takes a second

[Karma Supra]

Not quite. Radiater level can and will drop before the expansion tank if there is a leak in the system. More than the normal amount of coolant fom expansion tank will then be drawn back into the cooling system as it cools. This would then drop the level below normal and be an obvious sign of problems.

Nev

I was talking about checking in "cooled" state. to sumersise, -just look at the expansion tank and it'll give you an idea. - unless there is a presure problem where the presure is not low enough to draw coolant from the expansion tank to the radiator.

[Tallyman]

Wrong. It is pressurised by atmospheric pressure. Think about how the system works.

Nev

OK, but it's not pressurised above 1 atmosphere which is what most people regard as being pressurised.