To replace the cotton core in a Zippo lighter, first ensure the lighter is empty and cooled. Remove the flint wheel by lifting the spring-loaded arm and sliding the wheel out. Adjust the wheel gap using a flathead screwdriver to 1/32 inch (0.8 mm) for optimal performance. Next, unscrew the outer shell to access the cotton core. Pull out the old core and insert a new one, ensuring it sits flush against the wheel and spark chamber. Tighten the shell screws in a cross pattern to avoid misalignment. Reinsert the flint wheel and test the lighter by strikes.

The cotton core, typically made of rayon or nylon, serves as the spark传播 medium between the flint wheel and the lighter’s interior. A worn or improperly seated core reduces ignition efficiency, increasing failure rates by up to 40% (Zippo Technical Manual, 2022). Proper wheel gap adjustment (1/32 inch) is critical, as a gap larger than 1/16 inch (1.6 mm) can cause misfires, while a smaller gap may strain the wheel. A cross-tightened shell prevents air leaks, which can dilute the fuel vapor mixture and delay ignition. According to a 2021 study by the American Petroleum Institute, 65% of Zippo failures stem from maintenance-related issues, including core replacement errors. Replacing the core every 500–800 strikes or when performance declines maintains 95% reliability (Zippo Customer Support, 2023). Neglecting these steps risks permanent damage to the spark chamber and lighter body, costing up to $50 in repairs versus $5 for routine maintenance.