If your car is running hotter than it did when it was new, it may be suffering from a blocked or corroded radiator. All the new generation radiators have an aluminum core with plastic tanks. The aluminum radiators dissipate heat much better than their brass predecessors, however aluminum builds up more calcium deposits on the internal cooling tubes. These deposits drastically reduce the effectiveness of the radiator. Removing these deposits is almost impossible, since cleaning solutions that will dissolve the calcium will do the same to the thin, aluminum tubes.

Symptoms to look for:

• Vehicle has more than 80k miles, with the original radiator.
• Vehicle runs approx. 15%-20% hotter than normal. Highway speeds DO NOT reduce temperature.
• Fan clutch has been replaced, without significant improvement.
• Thermostat has been replaced without significant improvement. In many cases these vehicles have radiators with blocked cores which flushing will not remedy. The only solution in these cases is replacement of the radiator. But since flushing is considerably less costly than replacement, it’s sound practice to flush systems before investing in new radiators.

Flushing the system:

Before flushing the system, check the condition of the cooling system components. This will tell you which of them may need replacing when you have completed the flush. (see "Springtime Is Cooling System Time" for details).

When flushing the cooling system use a quality cooling system flush designed for modern aluminum core radiators. The product we recommend is Liqui-Moly Radiator flush.

Some hints:

• Flush the system with the old radiator and hoses in place.
• Replace hoses and radiator, if needed, AFTER flushing the system.
• Follow instructions carefully.
• Flush system with clear water for several minutes.
• Fill the system with high quality, name-brand antifreeze.