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.
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.
Powerful Performer: 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.
Corrosion Protection: 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 with the Bravo® drive.
Sporty Handling: 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.
HP / kW: 250 / 186
Maximum RPM (WOT): 4800-5200
Engine type: V6, 2-valve/cylinder pushrod
Displacement (L): 4.5
Displacement (CID/L): 275 / 4.5
Bore and stroke: 4.0 x 3.6 in. / 102 x 92 mm
Recommended fuel: Unleaded Regular 87 Octane Minimum (R+M/2) or 90 RON 10% Ethanol Maximum
Long-term protection from Mercury! Purchase a newMercury MerCruiser gas or inboard engine(installed in 2016 through 2020 model year boats) and get five years of limited coverage!
Five-year coverage against costly repairs
2016-2020 gas sterndrive/inboard models
More than 120 major engine parts covered
Entire engine assemblies replaced if necessary
World-classMercury dealerservice and support
EligibleMercury I.Q. Certified Boat Buildermodels
sold to US and Canada residents will receive 5 years coverage (2 years
of Mercury Limited Warranty and 3 years of Mercury Power of Protection
Limited Warranty). Valid on boats purchased from June 30, 2019 through
June 27, 2020 and registered by July 15, 2020. The information provided
in this document is intended to provide only a brief description of the
benefits of this Mercury 5-Year Gas Sterndrive and Inboard Engine
Limited Warranty. This Mercury Limited Warranty also has exclusions and
limitations that apply to the benefits discussed in this document. For
complete details as provided in the Agreement document (including “What
is not Covered”), please call the program administrator at 866.404.3064.