If your car's radiator has been punctured or has cracks in it, you'll then need to consider replacing it. Or, make do with repairing it, should the damage not be too severe. A radiator repair cost can vary wildly, going anywhere from $100 to upward of $800. If you need to re-seal a small puncture and flush (then re-fill) the coolant, it may cost you around $100 to $150 to do. These are relatively simple repairs. However, a full radiator replacement could cost you at least $500 and up, with a large part attributed to labor costs alone. This is at least cheaper than the thousands of dollars worth of fixes required should overheating occur.