2.22 Inspect And Replace Spark Plugs

INSPECT AND REPLACE SPARK PLUGS                                                                                             2.22
PREPARE                                                                      Table 2-21. Spark Plug Deposit Analysis
                                                                         DEPOSITS                      POSSIBLE CAUSE
                         A WARNING                                 Wet, black and shiny        Worn pistons
                                                                                               Worn piston rings
Gasoline is extremely flammable and highly explosive.
                                                                                               Worn valves
Keep gasoline away from ignition sources which could
                                                                                               Worn valve guides
result in death or serious injury. See the Safety chapter.
                                                                                               Worn valve seals
(00635c)
                                                                                               Weak battery
                                                                                               Faulty ignition system
1.    Remove main fuse.        See    POWER       DISCONNECT       Dry, fluffy or sooty and    Air-fuel mixture too rich
      (Page 8-4).                                                  black
                                                                   Light brown and glassy* Air-fuel mixture too lean
2.    Removing inner spark plugs:                                  (May be accompanied by Hot running engine
                                                                   cracks in the insulator or Valves not seating
      a.   Remove seat. See SEAT (Page 3-113).                     by electrode erosion.)     Improper ignition timing
                                                                   White, gray or tan and     Balanced combustion
      b.   Remove fuel tank. See FUEL TANK (Page 6-13).            powdery
                                                                   • T he glassy deposit on a spark plug may cause high speed
      c.   Remove air box. See AIR BOX (Page 6-3).                 misfiring.

      d.   Remove inner ignition coils. See IGNITION COIL          INSTALL
           (Page 8-16).
                                                                           FASTENER                      TORQUE VALUE
REMOVE                                                             Spark Plug                       89-133 in-lbs 10-15 N·m

                         A WARNING                                                             NOTE
                                                                   Always install new spark plugs. Do not reuse spark plugs that
Disconnecting spark plug cable with engine running can
                                                                   have been removed.
result in electric shock and death or serious injury.
(00464b)
                                                                   1.   Verify proper gap before installing new spark plugs, Refer
                           NOTE                                         to Table 2-22.
• If spark plugs are removed, they must be replaced with new
  ones.                                                                 a.    Use a wire-type feeler gauge within specification.
•    Never remove spark plug wires until heads have cooled.
                                                                        b.    Pass the wire gauge between the center and the
•    Clear area around spark plug of all debris before removing               outer electrodes.
     spark plug.
                                                                        c.    Adjust gap to within specification.
1.    See Figure 2-45. Remove spark plug cables (2) from outer
      spark plugs (1).                                             2.   Verify that spark plug threads are clean and dry.

2.    Thoroughly clean around spark plug base.                     3.   See Figure 2-45 and Figure 2-46. Install spark plugs (1).
                                                                        Tighten.
3.    Remove spark plugs.                                               Torque: 89-133 in-lbs (10-15 N·m) Spark Plug

INSPECT                                                            4.   Install spark plug cables or coils.

When removing spark plugs always install new spark
plugs.

1.    Inspect spark plug. Compare spark plug deposits, Refer
      to Table 2-21.

2.    Inspect spark plug cables. Replace as necessary.

     a.    Check for cracks or loose terminals.

     b.    Check for loose fit on ignition coil and spark plugs.

3.   Check cable boots/caps for cracks or tears. Replace as
     necessary.

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                                                                   Table 2-22. Spark Plug Gap
                                                       MODEL                    MM                     IN
                                                      All Models               0.7-0.8             0.027-0.032

                                                 COMPLETE

                                                 1.   Install inner   ignition    coils.    See IGNITION     COIL
                                                      (Page 8-16).

                                                 2. Install air box. See AIR BOX (Page 6-3).

                                                 3. Install fuel tank. See FUEL TANK (Page 6-13).

   1.       Spark plug (2)
                                                 4.   Install seat. See SEAT (Page 3-113).
   2.       Spark plug cable (2)
                Figure 2-45. Outer Spark Plugs   5.   Install main     fuse.     See       POWER    DISCONNECT
                                                      (Page 8-4).
  1555848

            2
   1.       Spark plug (2)
   2.       Cylinder head (2)
                Figure 2-46. Inner Spark Plugs

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