Tempest Introduces AT5K Spark Plug Resistance Tester

High internal resistance in aviation spark plugs is rapidly becoming a concern that many pilots and mechanics are beginning to recognize as a source of rough running engines and chronic magneto related problems.  Realizing that a growing number of maintenance facilities and pilot/owners are incorporating a spark plug resistance check as part of their preventive maintenance, Tempest felt it would be beneficial to make it as easy and efficient as possible to conduct such a test. Therefore, Tempest is pleased to introduce its AT5K resistance tester.



The Tempest AT5K resistance tester is a very efficient and effect means to test the internal resistance in all aviation spark plugs.  Simply place the spark plug, barrel side down, over the contact post and touch the other lead end to the firing end of the center electrode.  If the light is green, the spark plug resistance is below 4kΩ (thousand ohms).  If both the green and red lights are on, then the plug is between 4-5kΩ.  This is acceptable for serviceable plugs.  If only the red light is on, this indicates a resistance value in excess of 5kΩ and the plug should be discarded and replaced.   

Tempest AT5K resistance testers are in stock and available now at your authorized Tempest distributor.