ACDelco MR43T Specialty Marine Spark Plug

The ACDelco MR43T is a specialty marine spark plug designed for reliable everyday performance in jet boats, inboards, outboards, and personal watercraft. This replacement plug delivers efficient ignition in demanding marine environments where reliability is critical.

Key Features:

• High-quality copper core center electrode provides improved heat transfer to the tip for better resistance to low-speed carbon fouling
• Ribbed suppressor seal extends heat resistance and helps prevent spark flash over and misfires
• Maintains stable operating temperatures under varying load conditions
• Outstanding suppression characteristics for reliable performance
• Pre-gapped from the factory to manufacturer specifications
• Hot-tip insulator heats quickly and fires hot to promote longer electrode life

This spark plug is commonly used in Marine Power big block applications including 7.4L and 8.2L carbureted engines, as well as most carbureted and some throttle body injection engines in tournament ski and wakeboard boats. Also known by OEM part numbers 19157985, 19355200, and GM part number 5613438. Cross-references to Champion RBL8, NGK BR6FS, and Mercury 33-898264001.