There so also the top hose at both ends the Y that fits to the head, and the other end of the same hose the bend going into the radiator, some times the O-ring fails at that point.
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The seals can fail and the part it self sometimes goes brittle over time.
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Check the bend where it fits into the rad see if there is any red residue, same at the Y connector .
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Do not forget the coolant tank cap O-rings they can become flat and lose pressure then water can leak from the cap.
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So a few areas to check