Doesn’t work like that. The car would be having to run hot enough to create more pressure than what the cap is rated for. If what you’re saying was true cars would be spraying coolant all the time from the overflow.
🤦🏻♂️ No, the radiator cap regulates the pressure. As coolant gets hot it expands, raising the pressure. If too much pressure builds up the cap opens to decrease pressure and allow coolant to flow into the overflow reservoir.
It is an expansion tank, not an overflow hose on your boiler. This happens every time engine gets up to operating temperature. Coolant is not compressible, but expands a lot. If you look into expansion tank you can see how level fluctuate between hot and cold.
Your car would also be spraying coolant every time it warms up.
Doesn’t work like that. The car would be having to run hot enough to create more pressure than what the cap is rated for. If what you’re saying was true cars would be spraying coolant all the time from the overflow.
🤦🏻♂️ No, the radiator cap regulates the pressure. As coolant gets hot it expands, raising the pressure. If too much pressure builds up the cap opens to decrease pressure and allow coolant to flow into the overflow reservoir.
Exactly, when pressure surpasses the caps rating it will vent excess pressure which doesn’t happen often.
It is an expansion tank, not an overflow hose on your boiler. This happens every time engine gets up to operating temperature. Coolant is not compressible, but expands a lot. If you look into expansion tank you can see how level fluctuate between hot and cold.