Take control of your Mercury maintenance with this genuine NUT, (M8) Stainless Steel. Straightforward replacement that delivers factory results without shop labor costs.

Factory-built to exact Mercury Marine specifications, this component ensures reliable operation across all engine RPM ranges. Part number 400213 is manufactured to exact Mercury Marine factory specifications for precision installation and optimal performance. Constructed from premium marine-grade materials designed to withstand harsh saltwater and freshwater environments.

Factory parts exist for a reason — they work. Part 400213 undergoes rigorous Mercury Marine quality testing that aftermarket manufacturers skip. The result? Reliable performance season after season.

Compatible Mercury Marine Engines

FITS: 10HP MARINER, MERCURY (MAGNUM, MARATHON, SEA PRO)

• Fits MARINER, MERCURY 10HP engines
• Compatible HP: 10HP
• Model types: MAGNUM, MARATHON, SEA PRO
• Covers 24 serial number ranges
• Configurations: Outboard
• OEM genuine Mercury Marine part

COMPLETE SERIAL NUMBER COMPATIBILITY:

10HP Models

• 10HP MAGNUM (Mariner): 0D038000-0D279999, 0D281000-0G760299, 0G760300-0T979999, 0P017000-0P325499, 9596000-9792199, 9792200-0P016999
• 10HP MARATHON (Mariner): 0D038000-0D279999, 0D281000-0G760299, 0G760300-0T979999, 0P017000-0P325499, 0T980000-0T999999, 9596000-9792199, 9792200-0P016999
• 10HP SEA PRO (Mercury): 0D038000-0D279999, 0D281000-0G760299, 0G760300-0T979999, 0P017000-0P325499, 0T980000-0T999999, 9596000-9792199, 9792200-0P016999

Looking for your Mercury engine serial number? Our helpful guide shows you exactly where serial numbers are located on different engines.

Verification & Support

Verify part 400213 works with your Mercury using our parts finder tool. Have questions? Reach out using the contact buttons at the bottom of this page — our team is here to help by text, call, or email

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