Spark Plugs

Removal and Installation

Refer to the appropriate engine Section for spark plug Removal and Installation.

Refer to the Spark Plug Inspection Chart to determine the condition of the spark plugs.

Spark Plug Inspection Chart

Spark Plug Hole Taperset Installation

 CAUTION: Use protective eye glasses at all times.

NOTE: Cylinder head must be removed from vehicle to prevent metal shavings from entering engine.

Refer to appropriate engine Section for cylinder head removal and installation.

Tap

1. Thoroughly clean spark plug counterbore walls and seat of all dirt and foreign material.

2. Lubricate cutting threads of tap with cutting oil.

3. Engage tap pilot into spark plug port threads.

   NOTE: Use of power tools is not approved for installation of tapersets.

4. Using ratchet wrench and keeping tap aligned, rotate tap until depth stop collar bottoms on face of port and tighten against retaining ring.

5. Using an air hose, blow out as many shavings as possible.

6. If stop collar is loose, tap has not penetrated to full depth.

7. Remove tap from hole.

8. Clear shavings from hole and cylinder with air hose.

Installation

 CAUTION: Repeat Steps 1 through 8 to ensure a clean bore.

1. Lubricate mandrel threads and taperset with aluminum cutting coil. Then thread taperset onto mandrel with larger counterbore end toward 18mm (11/16 inch) hex body until one thread of mandrel shows beyond tip of taperset.
   
   
   
   

   NOTE: Taperset should be flush to 1mm (0.039 inch) below spark plug gasket seat.

2. Install taperset into tapped hole. Tighten 18mm (11/16 inch) hex to 68 Nm (50 lb-ft).

3. Holding 11mm (7/16 inch) hex mandrel to prevent rotation, loosen 18mm (11/16 inch) hex body approximately one-half turn to achieve breakaway action.

4. Remove tool from installed taperset.

5. Thoroughly clean cylinder head before installing spark plug. Tighten spark plugs to 9-20 Nm (7-15 lb-ft).