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Q: Coolant over flowing my radiator

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If coolants overflwin my radiator does it need to be replaced ?
My car has an automatic transmission.

Hi - if the radiator is overflowing while the engine idles (hot), but with the radiator or coolant recovery cap off - no, that doesn’t necessarily mean you have an overheating problem. Even idling, the engine will get hot enough to boil coolant with an "open" system. If, however, with the radiator/coolant recovery tank cap securely tightened, coolant is being ejected from the radiator cap or coolant recovery tank, that IS an indication of an overheating problem, and should be investigated. In that case, I would recommend a cooling system inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

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