HOW TO FLUSH A RADIATOR

Most drivers rarely think about their radiator until a cooling system problem occurs. Over time, contaminants, rust, and mineral deposits can build up inside the radiator, reducing cooling efficiency and potentially leading to engine overheating and damage.

The radiator is a critical part of your vehicle's cooling system. It allows coolant to circulate through a network of tubes where heat is transferred away from the engine and released into the surrounding air. Radiator fluid, also known as coolant or antifreeze, absorbs heat from the engine and transfers it to the radiator, where it is cooled before circulating back through the system.

As coolant ages, it can become contaminated with rust, scale, and other debris. Left unchecked, these contaminants may contribute to corrosion, reduced performance, and overheating. While simply draining the radiator removes some old fluid, it can leave behind contaminants and residual coolant that may dilute or contaminate fresh antifreeze. A coolant flush helps remove buildup and protects against corrosion.

Choosing the right cleaning product is important. Avoid using vinegar, as its acetic acid content can make metal surfaces more susceptible to corrosion over time. Bleach and bleach-containing products should also never be used, as sodium hypochlorite can damage aluminum, steel, engine components, rubber seals, and gaskets.

Simple Green Pro HD Heavy-Duty Cleaner is a non-corrosive formula designed for use on aluminum, stainless steel, and other metals. It helps break down grease, oil, grime, and automotive fluid residues without harsh corrosive ingredients.

Directions For How to Flush a Radiator:

Before beginning, consult your vehicle owner's manual for coolant specifications, capacity, and any manufacturer-specific procedures. Make sure the engine is completely cool before removing the radiator cap.

1. Dilute cleaner. In a large container, mix 1 part Simple Green Pro HD Heavy-Duty Cleaner to 15 parts water (1:15 ratio).
2. Drain radiator. Place a drain pan or other container beneath the drain cock opening on your radiator. Remove the fill cap from the top of the radiator. Use gloves or pliers to open the drain cock at the bottom of your car's radiator and drain the radiator. Dispose of the fluid properly. Replace the drain plug.
3. Add cleaner. Pour the cleaning mixture slowly into the fill hole on the top of the radiator. A funnel may be useful for this. Let the mixture remain in the radiator for 5 minutes.
4. Start engine. Turn on the vehicle and run the engine for 5-15 minutes to allow cleaner to cycle through the lines. The motor needs to warm up to operating temperature for the thermostat to open and allow coolant to flow from the radiator to and around the motor, then back.
5. Drain cleaning solution. Turn off the engine. Open the drain valve and allow the cleaning mixture to drain. Then replace the drain valve. Dispose of the used cleaner properly.
6. Rinse. Fill the radiator with clean water (if possible, use distilled, non-mineralized water). Turn on the engine and allow it to idle for five minutes. Then turn off the engine, open the drain valve again, and allow the water to drain. Replace the drain valve.
7. Add coolant. Add the recommended amount of coolant to the radiator.