Don’t miss another weekend. This genuine Mercury Marine STEM, CHECK UNIT ADAPTOR ships fast and installs easily – get back on the water where you belong.

Designed and manufactured to Mercury Marine OEM standards, this component ensures reliable operation across all engine RPM ranges. Part number 30187 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 30187 delivers consistent performance because it’s built right — the same way Mercury does it at the factory.

Compatible Mercury Marine Engines

FITS: 100-125HP MARINER, MERCURY

• Fits MARINER, MERCURY 100-125HP engines
• Compatible HP: 100HP, 110HP, 115HP, 125HP
• Covers 24 serial number ranges
• Configurations: Outboard
• OEM genuine Mercury Marine part

COMPLETE SERIAL NUMBER COMPATIBILITY:

100HP Models

• 100HP OUTBOARD (Mercury): 1464949-1768403, 1768404-2318585, 2641855-3253111, 2318586-2836018

110HP Models

• 110HP OUTBOARD (Mercury): 1870204-2314955

115HP Models

• 115HP OUTBOARD (Mariner): 4865178-5430526, 5430527-5738890, 5738891-6436122, 7191308-7208847, 8057045-8062459, 8062460-8062634
• 115HP OUTBOARD (Mercury): 5600967-6436122, 7147988-7208847, 2836019-3525440, 3525441-4855152, 7010763-7112248, 8008665-8051949

125HP Models

• 125HP OUTBOARD (Mercury): 2314956-2839368, 2641855-3253111

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

Verification & Support

Questions about part 30187? 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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