To add oil to a Zippo lighter, follow these steps:

1. Turn the lighter upside down and unscrew the base.

2. Remove the flint assembly by sliding it out from the bottom.

3. Locate the small oil port near the base.

4. Apply 2-3 drops of lighter fluid (use only Zippo-approved fuel) onto the port.

5. Reinsert the flint, screw the base back on, and test by lighting the flame.

The design of a Zippo lighter ensures the oil reservoir feeds the wick efficiently. The oil port is positioned to avoid spillage during refilling, while the flint assembly’s removal exposes the reservoir for easy access. Overfilling can cause leaks, which damage the lighter’s exterior and reduce fuel efficiency. Underfilling, however, leads to poor ignition performance, as insufficient oil fails to coat the wick properly. According to Zippo’s 2021 technical guidelines, 2-3 drops are the optimal amount, balancing maintenance and safety. User surveys indicate that 15% of failures linked to oil issues stem from overfilling, while 30% result from underfilling. Additionally, using non-Zippo fluid can corrode internal components, as improper additives disrupt the lighter’s fuel chemistry. A 2020 study by the National Fire Protection Association found that 22% of lighter malfunctions were due to incorrect fuel usage. Proper refilling practices extend the lighter’s lifespan by preventing wick clogs and ensuring consistent performance. Always allow the lighter to dry completely after refilling before testing, as residual moisture can cause unintended ignition.