What are the precautions for spark plug installation?

[OCameron]

Precautions for installing and replacing spark plugs: When removing the high-voltage distributor wires, mark each cylinder's position to avoid confusion. Use a spark plug socket to remove the spark plugs one by one. During removal, check for external debris such as leaves or dust and ensure thorough cleaning. Methods to determine if a spark plug is damaged: After removing the spark plug, observe its condition based on the following appearance colors. A normal spark plug's insulator skirt and electrodes should appear gray-white, gray-yellow, or light brown. A properly functioning spark plug has a reddish-brown insulator skirt, an electrode gap between 0.8-0.9mm, and no signs of electrode burn. If the spark plug is contaminated with oil or deposits but not damaged, it can continue to be used after cleaning. If the spark plug is severely damaged—showing signs of blistering, black streaks, cracks, or melted electrodes—identify the cause of the damage, resolve the issue, and replace the spark plug. Additionally, if the spark plug appears black as if smoked, it indicates incorrect heat range selection, a rich air-fuel mixture, or oil leakage.

[Wendy]

When replacing spark plugs myself, I pay special attention to details: The gap must be measured correctly, typically 0.7-1.1mm depending on the vehicle model, carefully adjusted with a gap tool; Cleaning is crucial—use a brush to clean the spark plug holes and threads to prevent metal debris from causing seizure; When tightening, use a torque wrench set to the recommended value (usually 15-25 Nm), applying even force without excessive load to avoid breaking the threads; Follow the ignition system design step by step, removing and installing one at a time to avoid confusion; Ensure good insulation, free from oil or moisture to prevent short circuits; Finally, double-check all installations before starting the engine—this prevents misfires and leaks, improves fuel efficiency, and extends engine life. As an enthusiast, I always bring all necessary tools for maintenance, performing tasks patiently to save on repair costs.

[Derek]

When doing DIY car maintenance, I always pay attention to several points when installing spark plugs: adjust the gap to around 0.8mm, as too wide or too narrow affects ignition; clean the threads with a small brush to gently sweep the hole, removing old debris to prevent sticking; tightening torque is crucial—rent a torque wrench and control it within the 18-22 Nm range (check the manual for specific values), never tighten by hand randomly; follow the engine design sequence, replacing one cylinder at a time without rushing; finally, ensure the insulation is normal, and listen for smooth engine sound before driving. I once suffered from not cleaning before installation, resulting in a stuck spark plug that cost over 300 yuan to fix. Always learn common mistakes, such as improper torque leading to air leaks or engine vibration, which is very dangerous.

[McAdalynn]

Installing spark plugs requires focusing on key points: precise gap, standard 0.7-1.0 mm; thorough cleaning, removing debris from threads to prevent rust; accurate tightening, using a torque wrench to control around 20 N·m; follow the firing order step by step when replacing; check insulation to prevent short circuits. Empirically, temperature control helps a lot—installing when the engine is cold is safer. If using anti-seize, apply it lightly and avoid overloading. These simple practices prevent oil leaks and misfires.