How to Clean Spark Plug Walls
- 1). Hold each spark plug by the boot, and remove it from its cable. Use angled, long-nose pliers if you cannot reach the spark plugs with your hands.
- 2). Unscrew each spark plug with a ratchet wrench. You likely will need to use a wrench extension to reach the plugs.
- 3). Inspect each spark plug carefully to determine whether you should clean or replace it. Plugs that are rusted or that show damaged electrodes will require replacement.
- 4). Use a bench vice to steady the spark plug while you clean it. Brush all the debris off the spark plug walls with the steel brush.
- 5). Sand the electrode gap with a fine-grade sandpaper, getting into the inner portions of the electrode gap at the base of the plug. Brush off the debris accumulated from cleaning.
- 6). Use a cleaning solvent applied to a cloth to remove any fuel and oil from the spark plug walls. Wipe off the excess cleaner with a dry cloth.
- 7). Replace the spark plugs and reconnect each cable.
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