Here's a comprehensive guide, covering both a complete flush and a less thorough method:
Method 1: Complete Flush (Most Thorough)
This method removes the most coolant and is recommended for significant contamination or if you're unsure of the previous coolant's age/condition.
Tools & Materials:
* New coolant: Use the correct type specified in your owner's manual (usually a 50/50 mix of coolant and distilled water). The capacity is approximately 10-12 quarts, but double-check your owner's manual for the exact amount.
* Drain pan: Large enough to hold at least 10 quarts of coolant.
* Wrench(es): For the drain plug(s) – you'll need the correct size to remove the engine block drain plug. A radiator drain petcock wrench might also be needed (if applicable).
* Funnel: To refill the radiator.
* Hose: A garden hose for flushing (optional, but highly recommended).
* Clean rags or shop towels: To clean up spills.
* Protective eyewear and gloves: Essential for safety.
* Coolant Flush Kit (optional but recommended): This kit contains chemicals that assist in removing scale and debris from the cooling system. Follow the kit's instructions carefully.
Procedure:
1. Cool Down: Let the engine cool completely. Hot coolant can cause severe burns.
2. Locate Drain Plugs: The engine block drain plug is usually located on the lower passenger side of the engine block. The radiator drain plug is located at the bottom of the radiator.
3. Drain the Coolant: Place the drain pan under the engine block drain plug and carefully remove the plug. Let the coolant drain completely. Then drain the radiator as well.
4. Flush with Water (Optional but Highly Recommended): Connect a garden hose to the radiator filler neck (with the cap removed) and run water through the system for several minutes. This helps dislodge loose debris. Let the water drain completely. Repeat if necessary until the water runs relatively clear. If using a coolant flush kit, follow its instructions at this stage.
5. Refill: Once completely drained, carefully add the new 50/50 coolant mixture using a funnel. Fill the radiator to the "full" line, then carefully add coolant to the overflow tank. Check your owner's manual.
6. Burp the System: Run the engine with the radiator cap OFF until the thermostat opens (you'll feel the hoses warm up) and the coolant starts circulating. Then, carefully add more coolant as needed to keep the radiator full. Check the overflow tank level.
7. Replace Radiator Cap: Once the engine is running and the coolant is circulating, replace the radiator cap.
8. Run the Engine: Let the engine run for about 15-20 minutes to allow the thermostat to open and close completely, ensuring the coolant circulates throughout the system.
9. Check Coolant Level: After the engine has cooled, check the coolant level in both the radiator and overflow tank. Add more coolant if needed.
Method 2: Partial Flush (Less Thorough)
This is quicker but less effective at removing contaminants.
1. Drain the Radiator: Drain only the coolant from the radiator.
2. Refill: Refill the radiator with the 50/50 coolant mixture.
3. Run the Engine: Run the engine and let it idle for a while, then let it cool down.
4. Repeat: Repeat steps 1-3 at least twice, or until the drained coolant looks relatively clean.
Important Considerations:
* Consult your owner's manual: Always refer to your Ford Expedition's owner's manual for specific instructions and recommendations. The procedures and coolant type might differ slightly based on your vehicle's exact specifications.
* Disposal: Dispose of the old coolant properly. Check your local regulations for safe disposal methods. Auto parts stores often accept used coolant for recycling.
* Air Pockets: Air pockets in the cooling system can cause overheating. Make sure you properly "burp" the system to remove any air. Some systems have bleed screws to help with this.
If you are not comfortable performing this task yourself, it's best to take your vehicle to a qualified mechanic. Improperly flushing the cooling system can lead to overheating and engine damage.
