I have a four cylinder side valve with a screw on radiator cap….I may not need an expansion tank but this is an EXCELLENT explanation for which I am very grateful indeed.
I have a question: how could the coolant in the expansion tank possibly be drawn back into the header tank or radiator? If you look at your pressure cap, there is a little brass disc in the middle of the tip which looks just like the anti vacuum one-way valve. These are fitted to stop a vacuum occurring which prevents collapse of the rubber hoses. So without a vacuum to suck back the coolant it would remain in the expansion bottle.
When the system heats, the water expands, pushing some out, past the cap valve. As the water cools it contracts, this will then create the vacuum you are refering to. Provided that the hose on the radiator overflow is in the bottom of the overflow tank then the same vaccum will suck the water back in the same way it went out.
It would be better to have a larger header tank or add another header tank and avoid using the unpressurised expansion tank which must be allowing oxygen into the coolant over time.
An expansion tank does just the opposite of that. It allows the coolant cap to burp out air in the system without spraying coolant everywhere. Since the hose inlet is always immersed in fluid, it does not allow gasses to re-enter the system.
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By far the clearest explanation of this part of a cooling system I have found, thanks!
Spot on. It was brilliant
I have a four cylinder side valve with a screw on radiator cap….I may not need an expansion tank but this is an EXCELLENT explanation for which I am very grateful indeed.
Great explanation. I finally understand how they work, thanks!
Thank you, sir, for explaining that to me in a way that I could understand.👍🤗
This was a great video, thanks so much!
Thanks for making this video. Explained it brilliantly👍
Thanks Boss, I was pulling my hair out trying to work out how to plumb in my charge cooler and didn't know if I need a header, or expansion tank.
First class explanation.. Many thanks!
Thanks so much !!! Excellent explanation your Awesome.
Thanks. Very clearly explained but hard to find information!
nice video, well explained
best explanation, the guy knows his stuff
Thanks. Perfectly explained.
Now I understand!, Thanks so much for sharing.
Very helpful!
Great job!
Would this remove the need for a filler cap in the radiator? i.e. you'd fill the radiator from this?
I have a question: how could the coolant in the expansion tank possibly be drawn back into the header tank or radiator? If you look at your pressure cap, there is a little brass disc in the middle of the tip which looks just like the anti vacuum one-way valve. These are fitted to stop a vacuum occurring which prevents collapse of the rubber hoses. So without a vacuum to suck back the coolant it would remain in the expansion bottle.
When the system heats, the water expands, pushing some out, past the cap valve. As the water cools it contracts, this will then create the vacuum you are refering to. Provided that the hose on the radiator overflow is in the bottom of the overflow tank then the same vaccum will suck the water back in the same way it went out.
very useful :)
well explained thanks for that
I have triumph stag but the expanding tank is lower than rad nearly these stags have tendency to overheat
It would be better to have a larger header tank or add another header tank and avoid using the unpressurised expansion tank which must be allowing oxygen into the coolant over time.
An expansion tank does just the opposite of that. It allows the coolant cap to burp out air in the system without spraying coolant everywhere. Since the hose inlet is always immersed in fluid, it does not allow gasses to re-enter the system.
He doesn’t say what brand tank that is I want to buy
How do I find the tanks he’s showing for buying
L.
www.carbuilder.com/uk/header-and-expansion-tanks#/pageSize=20&viewMode=grid&orderBy=15