Yamaha LF350USA 350HP 30″ Counter-Rotation Outboard

Description

The Yamaha LF350USA pairs 350HP with a 30-inch ultra-long shaft, built with counter-rotation gearing for multi-engine offshore boats. The 4.3-liter V6 handles extreme high-seas operation, distributing its 4256cc displacement over a 642 lbs dry weight. Built for deep-V sterns, the 30-inch shaft ensures complete propeller immersion on large catamarans and sportfishing boats in open ocean waters.

This powerhead sustains high-speed cruising across long tournament distances within its 5000-6000 RPM threshold. The 1.75:1 gear ratio translates combustion pressure into a torque curve that lifts wide hulls onto plane rapidly. Built on proven Japanese engineering, this platform is designed for mechanical consistency far beyond standard coastal ranges.

Technical Specifications of Yamaha LF350USA

• Electronic fuel injection delivers precise fuel atomization for complete combustion across the powerband.
• A 70-Amp gross alternator handles the electrical demands of modern multi-display helms.
• Integrated digital electric steering removes traditional hydraulic lines for streamlined rigging and responsive tracking.
• TotalTilt makes trimming easy with a built-in automatic tilt limiter for shallow waters.
• A 6.3-liter oil reservoir keeps components lubricated through long wide-open-throttle runs.
• The counter-rotation lower unit reverses propeller spin for balanced tracking on dual or quad-engine setups.

24-Valve V6 Block

The 24-valve DOHC V6 block is engineered to keep the powerhead’s weight down while accelerating thermal dissipation under severe high-load offshore operations.

Electronic Fuel Induction System

Electronic fuel induction pushes fuel straight into each intake track for complete combustion. This produces crisp throttle recovery and reliable starting when navigating treacherous inlets or heavy head seas.

Counter Rotating Gearcase Profile

Oversized drive gears housed inside a hydrodynamic lower unit keep drag profiles down during high-speed cruising. This engineering dampens gear-shift vibration while maximizing directional tracking on deep-transom multi-engine hulls.

Integrated Electric Steering System

Steer-by-wire deletes external hydraulic lines and valves for uncompromised helm response, coordinating with the high-capacity 70-Amp gross alternator to power critical open-water electronics.

Fiberglass Boat Hull Integration

Multi-engine offshore sportfishing boats, large center consoles, and catamarans in the 28-42 ft range are a strong match for this outboard. The 30-inch shaft prevents propeller ventilation climbing massive rollers in rough open-ocean swells.

Rapid Fluid Servicing Access Point

A multi-piece cowling detaches smoothly for quick dipstick checks, and drainage pathways isolate waste fluids for clean oil changes right at the marina slip. Pro Tip from the Shop: pull the gear lube plugs at the dock and use a lower unit pump to push fresh oil from the bottom up, keeping air pockets out of the gear housing.