[darkskiez]

The Mercury Optimax DFI engine is a 2-stroke direct injected motor made and designed by Mercury Marine. Originally introduced in 1995, the Optimax motor was made and sold until 2018, depending on your location the motors were sold under both the Mercury and Mariner names. The motors were made from a 1.5L 75hp, inline 3 cylinder configuration all the way through the 3.2L 300XS V6. This article will specifically focus on the Optimax fuel system, and the differences between the Optimax fuel system, and more conventional fuel systems. more

[franklions99]

Inline 3 Cylinder 1.5L Optimax Fuel Flow Diagram - 75hp, 90hp, 115hp, here

[angie2020]

Mercury states that the atomized fuel droplets are about 10 microns in size. All of these things in combination are what make the Mercury Optimax fuel efficient and powerful. The better the atomization, the more efficiently fuel can burn, thus giving exceptional power and fuel economy. here

[geebus]

Mercury Marine's 225 OptiMax is a Direct Fuel Injected (DFI) two-stroke. It is red hot. Interesting to note, its genesis was a collaboration between Mercury Racing and Mercury’s consumer outboard’s division. The wild child is a 3.0 liter V-6 powerhead mated to a Torque Master gearcase, replete with over-sized gears, bearings and special cooling water pickups. Translation: Mucho horsepower and a tough as nails personality, blended with race course proven reliability.

[tddert]

You should also know Mercury OptiMax motors light their fire with the Orbital Combustion Process (OCP). Essentially, this Australian technology shoots raw gasoline directly into the combustion chamber in the precise volume and at the optimal moment to build plenty of horsepower and minimal emissions. Compared to the obsolete conventional two strokes of yesteryear, Opti motors burn up to 45-percent less fuel. Another benefit, at the fuel dock 87 octane works just fine. Because it is an Adkins Diet-thin two-stroke, it tips the scales lightly. SmartCraft system view display is optional.

[xloem]

[justreen87]

[silverman]

Two days later with boat in water for first time I ran into the same problem. Boat would plane, miss, lose power, almost drop off of plane, catch, and speed would increase. It would finally settle into a 30 mph speed (GPS), run for a few minutes just fine and then miss, slow down, catch, and back to 30mph - most times. Sometimes it would lose power completely (very slowly) and eventually drop off entirely. I would put it in neutral, wait a couple of minutes, and then process would be repeated. When it was running good and I tried to increase power it would miss repeatedly and just would not go.

[jef.blanc]

That's all I know. Any thoughts appreciated.

[RusInfo]

I bought a boat, 1992 Hydrasports with 225 opti. It was supposed to be in good operating condition. During trial run engine would not hold power. It kept missing, slowing down, catching again, start to come up strong, miss, slow down, etc. We took it to Merc dealer who ran computer check and determined that the problem was a loose wire in the front of the engine. A sensor mistakenly thought it was much colder than it was so increased gas supply flooding engine - or some explanation like that. Wire tightened - problem solved. Circumstances compelled me to accept that info and get on the road for the 15 hour journey home.

[Koyama743]

Boat has new plugs and compression check is fine. Tach doesn't work. Temp guage seems to work moving into 100 plus degree range and staying there but who knows.

[Boytoat]

One important factor for me when I am looking for a new boat is the fuel economy. Some might argue that if you have to ask you can’t afford it and while that might be true with the cost of marine fuel and the low fuel economy of boating that can add up quickly.

[kosovito]

So I have decided to create a user-submitted database of boats and their fuel economy.

[sevyanfellow]

The following results are displayed in alphabetical order by boat make, newest first. Data is displayed in Statute MPG/MPH and is updated hourly from submissions.

[francc4iss96]