Key benefits Efficiently bleeds air from the cooling system during refilling, helping prevent air pockets that can cause overheating. Enables coolant to enter the engine as the thermostat opens and the engine reaches operating temperature. Reduces leakage risk by using the correct size adapter and keeping the gasket oriented with the gasket facing down. Simple setup and operation that helps control coolant flow and keep the refilling process cleaner. Compatible with vehicles when the correct adapter size is used. How it works and setup Start the engine and let it idle until it is hot enough to open the thermostat and run the cooling fan. After the thermostat opens to cool the engine, you may observe the coolant level drop and air or bubbles appearing, which indicates air escaping from the cooling system. Switch the climate control to hot and set the fan to off. This step helps ensure the heater core and related paths are in a proper state during the fill. Install the adapter of the correct size for your vehicle and tighten securely to prevent leaks. Place the gasket facing down. With the engine off, fill the coolant funnel about one third full when cold. This helps when the system burps, allowing liquid to enter the system rather than drawing in more air. Specifications and compatibility notes Adapter must be the correct size for your vehicle's fill port to ensure a tight, leak connection. Gasket orientation matters: place the gasket facing down for proper sealing. The process relies on warming the engine to the point where the thermostat opens and air is expelled as coolant level drops. Use scenarios After a complete coolant flush or replacement, to purge remaining air and ensure proper fill. Following thermostat replacement, water pump service, or radiator work where air may be trapped in the cooling system. In tight engine bays or complex cooling systems where traditional filling may leave air pockets, helping achieve a full, bubble fill. Notes This procedure emphasizes safe, controlled filling with the correct adapter size and proper gasket orientation to minimize leaks and rework. Always ensure the engine is at operating temperature during the purge phase and follow vehiclespecific guidance for coolant type and capacity.