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Spark Plug: Adjustments

Spark Plug Gap:






1. Disconnect spark plug cable from the spark plug.

CAUTION: Removal by pulling on the cables, may damage cables.

2. Using a plug wrench, remove all plugs from cylinder head.

CAUTION: Use care not to allow foreign matter to enter cylinder through spark plug holes.

3. Check the spark plugs for the following:
Broken insulator
Worn electrode
Carbon deposits
Damaged or broken gasket
Burnt condition of porcelain insulator at spark gap.

NOTE: Dark deposits indicate too rich a fuel mixture, light (white) deposits indicate too lean a fuel mixture, advanced ignition timing or insufficient plug tightening

4. Check plug gap using a plug gap gauge and adjust if necessary.

NOTE: Platinum tipped spark plugs can be identified by blue lines on the ceramic. Do not reuse them by cleaning or regapping. If platinum tip gap exceeds 0.051 in. (1.3 mm) replace spark plugs.

Standard value: .039 - 0.043 in. (1.0 - 1.1 mm)
Maximum value: 0.051 in. (1.3 mm)

5. Tighten spark plug to specified torque. If overtorqueing occurs, damage to threaded portion of cylinder head might result.
Spark plug torque: 15-21 ft-lbs (20 - 30 N-m)