Radiators will occasionally spring small leaks that can be fixed without replacing the radiator-here's how.
The location and amount of the coolant leak will determine if you can fix it your self. Leaks that are from a radiator hose can only be fixed by replacing the hose. Leaks that originate in the radiator can occasionally fixed by various "stop leak" products. Leaks that appear on the ground will likely require a major cooling system repair. However, if you have noticed that the cooling system reservoir needs coolant once in a while you can try a "stop leak" product.
Most radiators in modern cars are a combination of aluminum and plastic and are essentially a "throw away" part though they can sometimes be repaired. This is compared to radiators from older cars which were made of brass and soldered together. They rarely leaked (more often became plugged) and were easily repaired. Some modern cars have radiators made entirely of aluminum which is also easily repaired.
For example, I recently replaced the plastic/aluminum radiator in my 1997 Infiniti Q45. My local radiator shop said that they could repair the plastic tank (the leak source) for $125 or offered to sell me a new radiator for $150. I opted for the new radiator. However, before the leak became too large I used "Bars Leaks-radiator stop leak."
If you have a small radiator leak then it may be worth a shot to add a "stop leak" product. On my 1997 Q45 mentioned above I added "Bars stop leak" and was able to avoid replacing the radiator for about one year-a worthwhile success for a few dollars. Follow the directions on the bottle exactly as the product requires circulation in the cooling system to work.
