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I have 2005 Jeep Liberty, the radiator had a pin hole for the last few months i have been keeping water in it, then I had the radiator replaced yesterday and now i have another leak. I took the car back to my mechanic, and he told me that running just water has messed up the water pump. The water pump has never leaked until after the radiator was replaced. Is it just me or dose this seem a bit fishy? i mean how dose it not leak one day and then all of sudden it starts after the radiator was replaced. I would just like to know if this is common or am i being scammed.