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Our on-line store is open 24/7 and we ship Monday through Friday, excluding some holidays. Orders received for products without shipping restrictions on its product page will ship the same business day when received before 12:00 p.m. PST. Orders in high demand will have an estimated production time listed on its product page and will ship according to the date listed.
NGK 6431 BU8H Surface Gap Spark Plug.
NGK's Surface Gap Plugs are Nearly Immune to Pre-Ignition, and Usually Require a Special High Energy Ignition System. They Can be Susceptible to Fouling, Especially in Colder Applications, but May be Necessary in High Compression Applications.
Fits Mariner and Mercury outboard engines.
Specifications:
Shell
Thread Size: 14mm
Thread Pitch: 1.25mm
Seat Type: Gasket
Resistor: No
Reach: 12.7mm (1/2")
Hex Size: 13/16" (21mm)
Terminal Type: Solid
Overall Height: ISO
Gap: .016" (0.4mm)
Center Electrode
Material: Nickel
Type: Standard
Size: 2.5mm
Projection: Non-Projected
Ground Electrode
Material: Nickel
Type: Surface Discharge
Torque Specs: Cast Iron: 18-25.3 lb. ft. Aluminum: 18-21.6 lb. ft.
Brand: NGK
Heat Range: 8
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