[header] How to replace a leaking radiator hose [title] Begin by identifying the leaking radiator hose that needs to be replaced. [step] Do this by running the car to operating temperature. [substeps] Park the car on level ground with the engine running in park and emergency brake set. 
With the car running, visually inspect the hoses for collapse or leaks and do the same thing with the engine off. [title] Drain the engine coolant when it has cooled.