1. Preparation:
* Safety First: Disconnect the negative battery cable. Allow the engine to cool completely before starting. Wear safety glasses.
* Gather Tools: You'll need:
* Freeze plug installer/remover set: This is crucial. Avoid using screwdrivers or other makeshift tools as you risk damaging the engine block. The set usually includes various sizes of punches and drivers for installation and removal.
* Sockets and wrenches: To remove any components obstructing access to the freeze plugs. You'll likely need various sizes.
* Penetrating oil (like PB Blaster): Apply generously to the freeze plugs several hours (or even overnight) before attempting removal to help loosen them.
* Hammer: A ball-peen hammer is best.
* Pry bar (optional): May be helpful for stubborn plugs.
* New freeze plugs: Get the correct size and type (usually rubber or metal). Match the existing plugs for the best fit.
* Shop rags or towels: To clean up any coolant spills.
* Drain pan: To catch coolant.
2. Accessing the Freeze Plugs:
* Drain the coolant: Completely drain the cooling system. Locate the drain plug at the bottom of the radiator and the engine block.
* Remove obstructing components: Depending on the freeze plug's location, you might need to remove parts like the water pump, distributor, or other components to gain access. Take photos as you go to help with reassembly.
3. Removing the Freeze Plugs:
* Apply penetrating oil: Reapply penetrating oil if necessary.
* Use the freeze plug remover: Carefully center the remover punch on the freeze plug and gently tap it with the hammer. Work slowly and evenly to avoid damaging the block. If a plug is particularly stubborn, try applying more penetrating oil and letting it sit for a while. Gentle persuasion is key; avoid forceful hammering. Some plugs may require using the pry bar to help break the seal.
4. Installing the New Freeze Plugs:
* Clean the area: Thoroughly clean the holes where the old plugs were located to remove any rust or debris.
* Lubricate the new plugs: Lightly lubricate the new freeze plugs with some engine oil or grease. This will help them slide into place easily.
* Use the installer: Carefully align the installer with the hole and gently tap the new plug in using the hammer. Work evenly until the plug is flush with the engine block. Avoid hammering too hard, as you can deform the plug or damage the engine block.
5. Reassembly:
* Reinstall components: Reinstall any parts you removed earlier.
* Refill the cooling system: Refill the cooling system with the correct coolant mixture.
* Check for leaks: Run the engine and let it reach operating temperature. Carefully inspect for any leaks around the new freeze plugs. Top up the coolant as necessary.
Important Considerations:
* Engine Block Damage: If you damage the engine block during removal or installation, you'll need professional repair.
* Freeze Plug Size: Ensure you use the correct size freeze plugs. Incorrect sizes can lead to leaks.
* Professional Help: If you're uncomfortable performing this repair yourself, it's best to take your Nova to a qualified mechanic. This is not a beginner-level repair.
This is a general guide. The exact steps may vary slightly depending on your specific 1971 Nova 350 engine. Consult a repair manual specific to your vehicle for detailed diagrams and instructions. A shop manual (like a Chilton's or Haynes) will be extremely helpful. Remember patience and careful work are essential to avoid damage.
