You will need to drain the radiator to a level below the heater hose. Once it is drained, just unclamp both sides of the hose and replace. Refill the radiator. At this point, I recommend loostening the return line from the heater core where it mounts to the engine. Wait until coolant starts to come out (while filling). That way you know air is out of the system.

Answered by Jacobandnickolas (expert)
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