1 Spark Plugs

2 Spark Plugs ignite the air fuel mixture in the engine. ≈10,000 volts jump the gap between the center electrode & the ground electrode

3 Removing Spark Plugs 1. Remove plug wire by twisting off the spark plug wire boot Don’t pull the plug wire! Remove one spark plug at a time, or mark the plug wires so they can be installed in the same location!

4 use compressed air to blow out debris from around the spark plug use compressed air to blow out debris from around the spark plug use a spark plug socket & ratchet to remove the plug… use a spark plug socket & ratchet to remove the plug… Note the hex at the top & the rubber insert which differentiates this socket from standard sockets

5 Inspecting the Plugs Inspect for wear… Normal wear Excessive wear

6 Inspecting the Plugs Inspect for abnormal deposits… Oil Fouled Oil Fouled Fuel Fouled

7 Gapping New Spark Plugs find the spark plug gap specifications  use the under-hood tune-up decal or consult Mitchell

8  under-hood tune-up decal

9 Gapping the plugs use a plug gapping tool to set the gap use a plug gapping tool to set the gap the “L” shaped ground electrode is bent carefully the “L” shaped ground electrode is bent carefully do not use feeler gauges do not use feeler gauges

10 Apply a small amount of anti-seize compound to the spark plug threads – do not get any on the firing end of the plug!

11 Corroded or Carbonized Threads use a thread chaseruse a thread chaser stripped threads require a Heli-Coil insertstripped threads require a Heli-Coil insert

12 Installing the plugs… Install the spark plugs by hand first!!!

13 Tightening the plugs… use a torque wrench or a socket & ratchet to tighten securely use a torque wrench or a socket & ratchet to tighten securely Tapered seat plug: install by hand then tighten additional 1/16 to 1/8 turn Gasket type plug: install by hand then tighten additional ¼ to ½ turn

14 Types of plugs…