Royal Flush is an engine cooling system flush and cleaner that maintains and restores cooling system efficiency. Using a proprietary formula originally developed for cleaning high-end, industrial cooling towers and heat exchangers, Royal Flush contains unique technology not found in any other automotive cooling system flush and/or cleaner on the market. A highly concentrated product, Royal Flush helps remove oils, scums, gels, slimes, corrosion byproducts, and other contaminants. It is a one-step product that contains no acids, is completely safe to use, and does not require use of a post-flush neutralizer. It cleans the entire cooling system, neutralizes acidic build-up, and restores cooling efficiency.
Royal Flush maintains clean metal surfaces inside engines and radiators, which optimizes heat transfer. Over time, inhibitors in antifreeze, contaminants in water, and tiny rust particles become insoluble, and form antifreeze gels. Royal Flush contains industrial-grade detergents that chemically “scrub” surfaces inside the cooling system to remove contaminants. Using corrosion inhibitors that “prime” metal surfaces inside the cooling system, Royal Flush prepares the cooling system for follow-up treatment with Purple Ice.
- Optimizes cooling efficiency and prevents overheating
- Cleans radiator and entire cooling system
- Neutralizes combustion byproducts
- pH balanced to protect aluminum radiators
For best results use Royal Flush per the following instructions:
With the engine off and cool, open the radiator drain petcock and drain the coolant into a container for proper disposal. Close the petcock, pour in Royal Flush (for small systems like motorcycles the entire contents may not be appropriate), then fill with water. Replace the radiator cap, start the engine and turn the heater on high. Run the engine for at least 10-15 minutes or take a short drive. Please be aware that Royal Flush is completely safe for the cooling system and is non-corrosive. Therefore Royal Flush can be left in the cooling system for an entire day or more. If you choose to leave Royal Flush in the vehicle for an extended period, try to do this during a period of above freezing ambient temperatures. Neither Royal Flush nor Purple Ice provide any anti-freeze protection or boil over protection, so avoid overheating the engine.
After the flushing with Royal Flush is complete, turn off the engine, allow it to cool, open the drain petcock and drain into a disposal container. Then flush the system thoroughly with water. Close the petcock and refill the cooling system with straight water. Replace the radiator cap and run the engine again for at least 10-15 minutes. Turn off the engine, allow it to cool and drain and flush again with water as before. After the water flushing is complete, drain the water, close the petcock and refill with an appropriate water/antifreeze mixture for proper freeze protection in your region and replace radiator cap.
For questions on Royal Flush, call Royal Purple’s Tech Dept. at 888-382-6300.
Recommended Treat Rate
One(1) 12 ounce bottle will treat cooling systems with a coolant capacity of up to 16 quarts. For cooling systems with a coolant capacity of more than 16 quarts, it is recommended to use two (2) bottles of Royal Flush.
For best results and to improve heat transfer and corrosion protection also install Purple Ice Cooling System Optimizer and Conditioner
Purple Ice® is a high performance radiator conditioner. Its advanced 2-in-1 corrosion inhibitor and wetting agent provides year-round defense against corrosion. Purple Ice works by reducing the surface tension of the coolant mixture, which improves heat transfer and this can help reduce engine temperatures.
For more information, please check our Purple Ice FAQs.