CHAMPION CT-482 SPARK PLUG EROSION GAUGE

The Champion CT-482 spark plug erosion gauge provides a simple and accurate method for determining if your spark plugs have reached their maximum wear limit. Simply set the gap of the used spark plug to the nominal 0.4 mm (0.016 in.), then attempt to insert the electrode into the gauge's chamfered opening, as shown. If the electrode fits through the opening, the spark plug has exceeded its recommended wear limits and should be replaced.

The CT-482 is calibrated to reject spark plugs when their electrodes have eroded to at least half their original thickness. While aviation spark plugs will continue to operate beyond this wear point, the rate of electrode erosion accelerates due to electrode misalignment and the reduced spark surface area. This leads to intermittent misfires, increased wear on the ignition system and, potentially, unexpected and costly maintenance interventions.