BU8H Spark Plug | NGK 6431
BU8H Spark Plug | NGK 6431
NGK Spark Plugs
69 in stock
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BU8H Spark Plug | NGK 6431
Premium NGK spark plugs are known for their reliable performance and superior anti-fouling characteristics.
- NGK spark plug BU8H
- Stock number 6431
- 14mm thread size
- 12.7mm thread length
- Gasket seat
- Surface gap
- 13/16 in. hex
- Replaces Mercury 33-13686B2
- Replaces Mercury 33-13686Q

! Compatibility references are provided for informational purposes only and do not constitute a fitment guarantee. Part numbers, application listings, and "replaces" cross-references are based on manufacturer data and are intended as a starting point for identification — not a guarantee of fit for your specific engine, hull, or installation.
Buyer is solely responsible for verifying compatibility with their engine model, serial number, model year, and trim configuration before purchase. If you are unsure whether this part fits your application, contact MacombMarineParts.com before you buy — we're available via text, email, or online chat to help verify compatibility for your specific application.
MacombMarineParts.com is not liable for parts ordered based on assumed fitment. Returns due to buyer-selected incorrect fitment are subject to our standard return and restocking fee policies.