Featuring a host of engineering innovations, the 4.5L series establishes new standards for power-to-weight ratio, driver experience, acceleration, durability, and ease of maintenance.
- HP / kW 250 / 186
- Maximum RPM (WOT) 4800-5200
- Engine type V6, 2-valve/cylinder pushrod
- Displacement (L) 4.5
- Fuel delivery system Computer controlled Multi-Port Electronic Fuel Injection (MPI)
The specifications displayed here may not be indicative of the entire engine family; click on the “See All Models and Specs” link to view the specs in detail.
Named Top Product by Boating Industry
The Mercury Marine 4.5L 200hp sterndrive is a 2015 Boating Industry Top Product of the year.
The winning products were selected based on many factors, including innovation, impact on the industry, and how they advanced their category or created a new category.
In 2014, the Mercury MerCruiser 4.5L sterndrive engine was named an Innovation Award Winner at the International Boatbuilders Exhibition & Conference (IBEX).
Built for Marine
Designing a V-6 block solely for marine use allows Mercury to build the 4.5L with the ultimate protection system, using cast-iron componentry where the engine intersects with seawater, and using corrosion-resistant aluminum and composites everywhere else.
Thanks to its new, long-runner scroll intake manifold which draws in more air and converts it into additional torque, the 4.5L delivers a ground-breaking power-to-weight ratio and gives you V-8 power in a V-6 package.
Smooth & Quiet.
The 4.5L’s newly designed rear-facing throttle body, anti-whistle throttle plate, engine cover and mounts, lightweight flywheel, fuel-supply module, and structural oil pan all work together to deliver a superior idle, smoothness and low vibration. Resulting in an exceptional driving experience.
The MercFusion Paint System creates an outer seal against the elements, while MerCathode® provides automatic protection against galvanic corrosion. For maximum defense against saltwater effects, the SeaCore® industrial hardcoat anodizing system and closed-cooling circuit is available.
The 4.5L comes standard with Adaptive Speed Control, which automatically maintains engine rpm regardless of load or water conditions. The result is increased throttle response and a sporty feel.
Easy to Maintain.
When service is required, maintenance is a snap with the front-mounted drive lube monitor, color-coded maintenance points – including easy-to-reach oil filter and fill – and “how-to” videos that can be accessed via the QR code on the label.
Mercury® MerCruiser®: 4.5L
HP / kW
- 250 / 186
Maximum RPM (WOT)
- V6, 2-valve/cylinder pushrod
Bore and stroke
- 4.0 x 3.6" / 102 x 92 mm
- Unleaded Regular 87 Octane Minimum (R+M/2) or 90 RON 10% Ethanol Maximum
Fuel delivery system
- Computer controlled Multi-Port Electronic Fuel Injection (MPI)
- Performance-Tuned Scroll Intake Manifold
- SmartCraft PCM 112 Digital Inductive
Alternator amp / Watt
- 70 amp / 882 watt (Belt-Driven)
Water drain system
- Easy Drain "Season Extender"
- Through prop
- Water-cooled with thermostat
- Integrated wet sump
- NMMA Certified FCW 25W-40 Synthetic Blend
Dimensions (L x W x H)
- 28 x 30 x 22" / 696 x 740 x 559 mm
Weight (engine only)
- 756 lbs / 343 kg
- Bravo One
- Bravo Three
- Bravo Two