Mercury Racing

Mercury 300R FourStroke

Mercury 300R

Custom Racing intake cam profiles and short intake manifold runners maximize power throughout the rated speed range. An integrated oil cooler keeps oil temps down throughout the Racing exclusive 5800-6400 rpm operating range.
Transient spark calibration boosts torque by 7% for unmatched acceleration. Advanced Range Optimization automatically adjusts fuel delivery for up to 10% improvement in cruise-speed fuel efficiency.
All of this on 87-octane (90 RON) pump fuel while maintaining a comparable weight as it’s legacy two-stroke cousin. Best of all, the 300R is backed by a three-year factory warranty.


Rated Horsepower (HP/kW)

Bore & Stroke (IN/MM)
3.6 X 3.4/92 x 86

Idle RPM