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Old 08-04-2013, 01:15 PM
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bluebee bluebee is offline
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Originally Posted by John in VA View Post
I thought that as the coolant was heated, it "expanded" and moved from cooling system (radiator) to the expansion tank.
If that were true, then there would be no need for the expansion tank cap to vent the coolant, which, clearly, this thread indicates is what happens.

So, that leaves open the question of what the so-called "overflow" hose does.

Maybe that overflow hose might just an air-only equalizer?
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Last edited by bluebee; 08-04-2013 at 04:59 PM.
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