Product Overview
NGK Standard Nickel Plug 6431
Keep your marine engine purring like a kitten with the NGK Standard Nickel Plug 6431 (BU8H). This reliable spark plug is engineered for optimal performance and longevity in harsh marine environments. Its specialized design resists fouling and corrosion, ensuring smooth starts and consistent power delivery, so you can focus on enjoying your time on the water.
Key Features
- **Surface Discharge Design:** Virtually eliminates pre-ignition issues, providing reliable performance even under high compression.
- **Nickel Alloy Construction:** Offers excellent durability and resistance to wear in demanding marine conditions.
- **Trivalent Metal Plating:** Superior corrosion and seizure resistance ensures long-lasting performance and easy removal.
- **Corrugated Ribs:** Prevents flashover for a consistent and reliable spark.
- **Pure Alumina Silicate Insulator:** Provides superior strength and improved heat transfer for optimal engine efficiency.
- **Copper Core:** Aids in heat removal, extending the plug's lifespan.
- **Precisely Gapped at .016" (0.4mm):** Optimized for efficient fuel combustion and smooth engine operation.
- **Specifically designed for Mariner and Mercury Outboards (see fitment guide):** Ensures compatibility and optimal performance for your specific engine.
Specifications
Shell Thread Diameter14mm
Thread Pitch1.25mm
Seat TypeGasket
Reach12.7mm (1/2")
Hex Size13/16" (21mm)
Terminal TypeSolid
Overall HeightISO
Gap.016" (0.4mm)
Center Electrode MaterialNickel
Center Electrode TypeStandard
Center Electrode Size2.5mm
Center Electrode ProjectionNon-Projected
Ground Electrode MaterialNickel
Ground Electrode TypeSurface Discharge
ResistorNo
Resistor Value1K Ohm
Heat Range8
Torque Specs (Cast Iron)18-25.3 lb. ft.
Torque Specs (Aluminum)18-21.6 lb. ft.
BrandNGK/NTK
The Captain's Take
After years of battling unreliable spark plugs in my charter boat, I switched to NGK 6431s and haven't looked back. These plugs deliver the dependable starts and consistent performance I need, even in challenging conditions. They're a small investment that makes a big difference in the reliability and enjoyment of my boat.
Warranty Information
60 Days
