Why pay dealer markup? Get genuine Mercury Marine quality at discount pricing. This COUPLING delivers OEM reliability with savings up to 20% below retail.

Manufactured to strict Mercury Marine quality standards, this component ensures reliable operation across all engine RPM ranges. Part number 18643A7 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.

Cut-rate alternatives might look similar, but they’re not engineered to Mercury’s exacting standards. Part 18643A7 delivers consistent performance because it’s built right — the same way Mercury does it at the factory.

Compatible Mercury Marine Engines

FITS: 5-350HP MERCRUISER

• Fits MERCRUISER 5-350HP engines
• Compatible HP: 5HP, 200HP, 230HP, 260HP, 350HP
• Covers 8 serial number ranges
• Configurations: Outboard
• OEM genuine Mercury Marine part

COMPLETE SERIAL NUMBER COMPATIBILITY:

5HP Models

• 5HP OUTBOARD (Mercruiser): 0B774445-0F600999, 0B773740-0F600999, 0B525982-0F600999

200HP Models

• 200HP OUTBOARD (Mercruiser): 0B525982-0B774444

230HP Models

• 230HP OUTBOARD (Mercruiser): 0B525982-0B773739

260HP Models

• 260HP OUTBOARD (Mercruiser): 0B525982-0B773739, 0B525982-0B773304

350HP Models

• 350HP OUTBOARD (Mercruiser): 0B525982-0F600999

Don’t know where your serial number is? Our quick reference guide shows exactly where to find it on Mercury Marine engines.

Verification & Support

Questions about part 18643A7? Use our parts finder tool to verify fitment yourself. Prefer to talk to an expert? Use the contact buttons at the bottom of this page to reach our team by text, call, or email

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