Genuine Mercury Zephyr Spark Plug

Mercury Zephyr Spark Plug Parts Questions & Answers

• Spark Plug
  ASF-42-C
  Q: How to remove and install spark plug on Mercury Zephyr?

  A: Before removing any spark plug wires, ensure they are properly numbered as to their original location. Mark the wires with tape if necessary or remove only one plug at a time so that the wires are always in order. Remove each spark plug wire by grasping the molded boot, twisting it slightly and then pulling it away from the end of the spark plug. Do not pull on the wire itself because it could separate the connector inside the boot. If this happens, the wire must be replaced with a new one. Using an insulated spark plug socket, loosen each spark plug about two turns and carefully clean around the plug hole so that no dirt can enter when the plug is removed. Fully remove each of the spark plugs by hand. Inspect the firing ends of the plugs for deposits and electrode condition. Inspect the insulators for cracks and discoloration. If the plug appears usable, clean it with a wire brush to remove carbon deposits from the electrodes and threads. Use a small file to clean the electrode surfaces. Set the spark plug electrode gap to the setting on the emission control decal by bending the outer electrode, never the center one. Position each plug into its cylinder head port and thread into the hole by hand. Fully tighten each of the plugs to the proper torque. Using a clean standard screwdriver, apply a thin film of silicone grease on the entire interior surface of the spark plug wire boot. Push each of the spark plug wires into position on the ends of the plugs, again using a twisting motion to fully seat the boots. Make sure that the wires are re-installed in their original positions. Uncover or re-connect the battery.