Mercury F9.9 EFI 9.9HP FourStroke Outboard Motor (Lightweight, Powerful, EFI Equipped)

he Mercury F9.9 EFI sits at the top of Mercury’s portable range, delivering nearly double-digit horsepower while remaining easy to transport. At 9.9HP, this engine can push your boat to impressive speeds and handle heavier loads with ease – all without exceeding the 10HP mark. In many regions, staying below 10HP means boaters can avoid registration or licensing hassles (especially when the boat is under ~4.5 m), making the F9.9 EFI particularly attractive for recreational use. Thanks to its EFI technology, the F9.9 starts effortlessly in any weather with no choke or priming needed. It runs smoothly and efficiently, and at around 38–40 kg (depending on configuration) it’s still manageable to install or remove when needed.

• High Performance, Low Hassle: With 9.9HP of output, this motor can get small boats on plane and confidently propel heavier loads. It’s perfect for anglers with fully loaded jon boats or families with RIB inflatables who want extra power without a significantly heavier engine. By staying under the 10HP (~7.3kW) limit, the Mercury 9.9 allows for hassle-free boating without mandatory registration in many jurisdictions (when paired with boats up to 4.57 m in length).
• Electronic Fuel Injection Advantages: The EFI system eliminates starting frustrations – the engine fires up quickly and reliably whether on a cold morning or after months of storage. EFI automatically fine-tunes the fuel mixture for smooth acceleration and yields up to 30% better fuel economy compared to older 9.9HP carbureted models. This means you can venture farther on a tank of fuel and enjoy cleaner running with less exhaust smell.
• Portable & Easy to Handle: Designed with portability in mind, the Mercury 9.9 EFI has built-in carry points and a moderate weight (~38 kg), making it one of the lightest in its class. One person can mount or dismount the engine, which is great for boaters who trailer their boats or need to stow the motor when not in use. You get the benefit of high power in a package that’s still truly portable.
• Smooth, Quiet Operation: Mercury engineered this twin-cylinder engine to minimize vibration by using a balanced powerhead and soft rubber mounts. The result is a smooth, quiet ride – you can troll for fish or cruise around without your hand going numb from tiller buzz. The through-prop exhaust releases underwater, further reducing noise and exhaust fumes for a more pleasant boating experience.
• Versatile Control: The standard tiller handle consolidates all controls – shifting (F-N-R), throttle, and steering – into one hand, with adjustable friction for throttle and steering tension. The Mercury F9.9 EFI is offered in both manual and electric start versions, as well as short (15″) or long (20″) shaft models to perfectly match your boat’s transom height. (There are even specific variants like a remote-steer version or a power tilt ProKicker edition for specialized uses such as precise trolling on larger boats.) This versatility means you can configure the F9.9 to suit your exact needs and enjoy confident handling in any scenario.