Thread: 350 Engine question

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Sounds like your plugs look fine - here's a good reference guide for plugs from our friends at NGK:

Normal: Grey to Light Golden-Brown Color
• This condition is ideal, the spark plug and engine air/fuel mixture are operating properly.
Dry: Black Soot Buildup
• Air/fuel mixture is too rich, the carburetor settings are incorrect, or the flame arrestor is dirty or has mounting problems.
• Spark plug heat range is too cold for the operating conditions.
• Ignition system problems causing a weak or intermittent spark.
Wet Fouling: Shiny, Wet, Black Appearance
• Excessive use of the choke (gas fouled)
• Prolonged low rpm operation (gas or oil fouled)
• Fuel to oil ratio is too rich (oil fouled)
Excess Deposits: Bumpy, Chalky Buildup
• Poor fuel quality
• Oil leakage into combustion chamber
• Improper oil used for premix/injected
Overheated: White, Blistered, Melted Electrode
• Lean air/fuel mixture
• Spark plug heat range is too hot for operating condition of the engine
• Plug is not properly gapped and/or torqued onto head
• Overly advanced timing