Here's a general outline. Specifics might vary slightly depending on the exact location of the plugs:
I. Preparation:
1. Safety First: Disconnect the negative battery terminal. Wear safety glasses and gloves.
2. Drain the Cooling System: Completely drain the coolant from the engine. This is crucial to avoid a messy job and potential burns. Locate the drain plug at the bottom of the radiator and engine block. Open the radiator cap as well.
3. Gather Tools and Materials: You'll need:
* Socket set (various sizes, including deep sockets)
* Ratchet and extensions
* Hammer (preferably a rubber mallet)
* Pry bar (or a screwdriver with a rounded end)
* Freeze plug installer/punch (essential to avoid damaging the new plugs) – This tool is specifically sized to the freeze plug size.
* New freeze plugs (the correct size and type – get these from a parts store, providing your vehicle's year, make, and model)
* Penetrating oil (like PB Blaster)
* Jack stands or a vehicle lift
* Drain pan
* Clean rags or shop towels
* New coolant (the correct type for your engine – check your owner's manual)
II. Removing the Freeze Plugs:
1. Access: Locate the freeze plugs you need to replace. This often requires removing various components, which may include parts of the exhaust system, possibly the alternator, and/or other accessories. Consult a repair manual for precise locations and removal instructions for your specific engine. Take pictures as you go to aid reassembly.
2. Penetrating Oil: Apply penetrating oil around the outer edges of each freeze plug to help loosen them. Let it soak for at least 30 minutes.
3. Removal: Use a socket that's slightly smaller than the freeze plug (a socket that fits snugly on the outer edge). Carefully tap the socket onto the plug using a hammer. Gently tap the plug out, being careful not to damage the surrounding engine block. If the plug is stubbornly stuck, use a pry bar carefully to help it break free. Be patient and work slowly to avoid damaging the engine block. If you damage the block during this step, you'll likely need professional help.
III. Installing New Freeze Plugs:
1. Clean the Surface: Thoroughly clean the freeze plug seating area in the engine block. Remove any rust, debris, or old gasket material.
2. Lubrication: Lightly lubricate the new freeze plugs with engine oil or grease.
3. Installation: Use the freeze plug installer/punch to carefully install the new plugs. This tool is crucial to prevent damaging the new plugs and ensures a proper fit. This involves carefully pushing the new plugs into the holes.
4. Check for Flushness: Make sure the new freeze plugs are flush with the engine block surface.
IV. Reassembly:
1. Reinstall Removed Parts: Carefully reinstall all the components you removed in step II. Reference your pictures!
2. Refill Cooling System: Refill the cooling system with the correct type and amount of coolant. Refer to your owner's manual for the proper coolant type and capacity.
3. Bleed the Cooling System: Bleed the air out of the cooling system according to your owner's manual instructions. This is critical to prevent overheating.
4. Check for Leaks: Run the engine for a few minutes and check for any leaks around the new freeze plugs and other connections.
V. Important Considerations:
* Repair Manual: A repair manual specific to your 1999 Mercury Sable 3.0L engine is highly recommended. It will provide detailed diagrams, torque specifications, and step-by-step instructions.
* Patience: This is a time-consuming job. Be patient and take your time. Rushing can lead to mistakes and damage.
* Professional Help: If you are unsure about any step of this process, seek professional help from a qualified mechanic. The cost of repairing engine damage far outweighs the cost of professional labor.
This is a general guide. Always refer to a repair manual specific to your vehicle for detailed instructions and torque specifications. Improperly replacing freeze plugs can lead to serious engine damage. Proceed with caution and be aware of the risks involved.
