OptiMax 1.5L 75 HP


The most experience for the greatest value.

No direct injection engine has more experience, testing, or success under its belt than Mercury OptiMax. It’s not surprising that OptiMax repeatedly leads every direct injection category – including power, fuel efficiency, reliability, and versatility. It all adds up to a complete line of power that delivers more, and delivers it better. OptiMax remains the best value on the water and a top choice of boaters..


Engine Specs

  • Displacement (CID/cc) : 92.96 / 1526
  • Cylinder/Configuration : 3 (in-line)
  • Bore & Stroke (in/mm) : 3.63 x 3.00in / 92 x 76mm
  • Fuel System : 2-stage Direct Fuel Injection (DFI)
  • Cooling System : Water-cooled with thermostat & pressure-controlled
  • Full Throttle RPM Range : 5000-5750
  • Ignition System : PCM Digital Inductive
  • Starting : Electric (turn-key)
  • Alternator Amp : 60 amp / 756 watt
  • Gear Shift : F-N-R
  • Steering : Big Tiller Compatible, Remote
  • Trim System : Power Trim
  • Recommended Oil : Mercury OptiMax/DFI Outboard Oil
  • CARB Star Rating : 3
  • Remote Fuel Tank : optional
  • Exhaust System : Though prop
  • Compatible with Smartcraft Digital Technology : Yes
  • Dry Weight * Lightest model available : 375lbs / 170kg
  • Engine Protection Operator Warning System : Low oil level, Overheat, Over-rev, SmartCraft Engine Guardian
  • Gearcase Ratio : 2.33:1
  • Recommended Fuel : 87 octane/up to 10% ethanol


  • HP/Kw @ Prop : 75 / 55.1
  • Shaft Length : 20 in (508 mm)
  • Shallow Water Trim Range : 20 degrees


Standard Features

Specifications are subject to change without notice


  • A Prop For Every Purpose: No one offers a wider variety of propellers than Mercury Marine. From our four-blade, stainless steel Trophy Plus to the revolutionary Enertia, Mercury makes a prop that will maximize your boating enjoyment. Visit the Mercury Prop Selector to choose the prop that’s right for you.
  • Leading Gearcase Technology: No other marine engine company has more knowledge about hydrodynamics and gearcase design than Mercury. We have the right gearcase configuration and technology to match any boating application. Our designs result in less drag – giving you better handling and performance.
  • Light And Fast: The inline 3-cylinder design is slim and lightweight making it a great choice for almost any type of boat. It consistently outperforms other DI engines in holeshot, mid-range acceleration and top-end speed.
  • Long-Lasting Stainless: OptiMax is built with more stainless steel and corrosion-resistant components, which translates to saltwater durability, longer intervals between maintenance, and lower cost of ownership. In addition, our lower-pressure direct-injection system also provides superior component durability and longevity.
  • Powerful And Smooth: The OptiMax Two-Stage Direct Injection System provides a constant supply of atomized fuel and air while the Vapor Separator Tank (VST) ensures a constant supply of liquid fuel for the injection process. The result is unmatched throttle response, instant starting, and smooth performance.
  • Superior Durability: OptiMax’s durable gearcase features a heavy-duty prop shaft and Mercury-patented dual water pickups on the front end of the torpedo for a constant flow of cooling water. It is specifically designed to give you impeccable handling and incredible top speeds. Dome-Shaped Piston Heads direct the fuel-and-air charge to the spark plug more efficiently, providing outstanding durability along with excellent running quality.
  • Ultimate Efficiency: The innovative OptiMax DI system delivers the ultimate in efficiency, squeezing more miles and performance from every drop of fuel. The exclusive deflector-shaped pistons and combustion chambers enhance fuel economy and lower emissions by efficiently directing the fuel/air charge to the spark plug. The OptiMax Air Compressor provides a steady charge of cooled air for maximum combustion efficiency.