The Sierra 18-99211 is a direct-replacement RPM limiter (rev limiter) designed for Mercury and Mariner 2-stroke outboard and SportJet engines requiring a 5200 RPM limit. This ignition system component safeguards the engine by electronically preventing over-revving, protecting internal components from damage under wide-open-throttle conditions.
Sierra is a trusted name in marine aftermarket parts, engineering this RPM limiter to meet or exceed OEM specifications for a precise, plug-and-play fit.
Key Features:
- 5200 RPM electronic rev limiter for 2-stroke Mercury/Mariner outboard engines
- Compatible with 2-cylinder, 3-cylinder, and 4-cylinder engine configurations
- Covers a broad application range spanning model years 1992–2006
- Also fits Mercury SportJet 2-stroke applications
- Direct OEM replacement — no modification required for installation
- Engineered to meet or exceed original Mercury performance standards
Replaces OEM Part Numbers: 821889A19, 821889A22, 821889A28, 821889A29, 821889A34, 821889A40, 821889A41, 821889A42, 821889A45, 821889A46, 821889A47, 821889A49, 821889A50, 821889A51, 821889A53
Cross-references CDI Electronics 144-1889-51. Always verify your engine's required RPM limit before installation — do not interchange 5200 RPM and 5800 RPM limiters.
