Safety First:
* Hot coolant burns! Let the engine cool completely before starting.
* Wear safety glasses and gloves.
* Work in a well-ventilated area.
* Dispose of used coolant properly. Check with your local regulations for proper disposal methods.
Materials You'll Need:
* New coolant: Use the correct type specified in your owner's manual (usually a 50/50 mix of coolant and distilled water).
* Drain pan: Large enough to hold several gallons of coolant.
* Wrench(es): Appropriate sizes for your drain plug and coolant hoses (if you choose to remove them).
* Funnel: For refilling the radiator.
* Hose: A length of hose can help direct the coolant into your drain pan.
* Coolant flush: Consider using a commercial engine block flush product (follow the product instructions carefully).
* Water hose: For rinsing (optional, but recommended).
Procedure:
1. Locate Drain Points: Find the drain plug on the engine block (usually low on the block, often near the oil pan) and the drain petcock on the radiator.
2. Drain the Coolant: Place your drain pan under the drain plugs. Carefully open the radiator petcock first to allow for some initial draining. Then open the engine block drain plug. Allow the coolant to drain completely.
3. (Optional) Use a Coolant Flush: Follow the instructions on your chosen commercial coolant flush product. This usually involves adding the flush to the system, running the engine for a short period, and then draining again.
4. Rinse (Optional but Highly Recommended): After draining the old coolant, connect a garden hose to the upper radiator hose opening (after removing the hose). Run water through the system until the water runs clear. This step is crucial for removing sediment and debris. Then drain the water.
5. Refill and Bleed: Reinstall the drain plugs. Add the 50/50 coolant/distilled water mix to the radiator until it's near the top of the filler neck. Start the engine and let it run until it reaches operating temperature. Monitor the coolant level. Air pockets can form, leading to overheating. Check for leaks.
6. Bleed the System: Some Lumina models have a bleed valve or screw on the thermostat housing. If so, open it to release any trapped air. Squeeze the upper radiator hose to help dislodge any air bubbles. Continue to add coolant as needed. Consult your owner's manual for specifics on bleeding the system.
7. Check Coolant Level: Once the engine is cool, check the coolant level in the radiator and add more coolant if necessary to reach the "full" level.
8. Inspect for Leaks: Check for any leaks around the drain plugs, hoses, or clamps.
Important Notes:
* This is a general guide. Specific procedures might differ slightly based on your engine and vehicle.
* Using a pressure tester after the flush helps verify the cooling system integrity.
* If you're unsure about any step, consult a qualified mechanic. Flushing the coolant improperly can lead to engine damage.
This process can be messy and time-consuming, so be prepared. If you're not comfortable doing this yourself, it's best to take your Lumina to a professional mechanic. They have the tools and experience to perform the job correctly and safely.
