Just trying to figure out some things related to expansion tank caps.

1. If the inner seal of the cap is compromised/deteriorated, what is the effect? I'm assuming lower of system pressure and potentially loss of coolant but wanted to confirm.

2. If the cooling system has a recovery tank that is in good working order, will that prevent a bad expansion tank cap from resulting in a loss of coolant?

3. Is there a certain risk in replacing a bad cap on an older cooling system in that the increase of pressure might cause something else to fail?

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