Propulsion engine F350

outboardgasolineboating

Overview The 4.3L V6 Offshore F350 is a high-displacement V6 outboard engineered for serious offshore applications. It combines a lightweight design with a high compression ratio to deliver class-leading power-to-weight performance for professional and recreational operators.

Power & Weight Producing 350 HP while weighing approximately 629 lb (shortest shaft), the F350 achieves an 11.0:1 compression ratio and an exceptional power-to-weight advantage of more than 65 lb over comparable units. Available finishes include Yamaha gray, pearlescent white and classic white.

• Recommended fuel: Octane 89
• Shaft lengths available: 25 in, 30 in and 35 in
• Alternator output: up to 70 amp

Compatibility Compatible with digital controls and a wide range of gauges and propellers, the F350 supports tailored setups for performance, control and data display to meet commercial and leisure requirements.

Features & Benefits

• Responsive Power: Center-mounted 81 mm electronic throttle valve (8% larger than F300) and balanced intake manifolds for smooth airflow and immediate throttle response.
• Improved Combustion: Camshaft profile with higher valve lift and redesigned lifters for longer valve opening duration and more precise combustion control.
• Max Torque: New clutch dog with increased tooth count for enhanced torque transfer from powerhead to propeller.
• Charging Capacity: 70-amp alternator delivers more than 30 net amps per outboard at idle—nearly double similar Yamaha outboards—supporting onboard electronics and systems.
• Increased Power Output: Iridium spark plugs and updated fuel injection mapping enable longer injector duration for higher power delivery.
• Helm Master EX Compatibility: Supports full joystick control (one to five engines), wireless control options, autopilot modes and extended automation; optional theft-deterrent system available.
• TotalTilt: Fast double-tap full trim up/down for quick trailering and full-tilt operations.
• Thrust-Enhancing Reverse Exhaust: Keeps exhaust bubbles away from the propeller below 2500 RPM and in reverse to improve reverse thrust and control.

Technical Specifications

• Weight: 286 kg (629 lbs) / 291 kg (642 lbs) / 296 kg (653 lbs) (refers to shortest shaft length)
• Full Throttle RPM Range: 5000 – 6000 rpm
• Fuel Induction System: EFI
• Recommended Engine Oil: Yamalube® 4M (see owner's manual)
• Engine Type: V6
• Displacement: 4.3 L
• Bore x Stroke: 96 x 98 mm (3.78 x 3.86 in)
• Prop Shaft Horsepower: 350 @ 6000
• Alternator Output at W.O.T.: 50 – 70 amp
• Compression Ratio: 11.0:1
• Recommended Fuel: Octane 89
• Recommended Fuel Filtration: Yamaha 10-micron fuel/water separating filter (external)
• C.A.R.B. Rating: 3 Star
• Exhaust: Through propeller (except in reverse under 2500 RPM)
• Intake: 24
• Ignition: TCI microcomputer
• Spark Plug: ILMAR7E-9 / Iridium
• Starting System: Electric with PTT
• Lubrication: Wet sump
• Engine Oil Capacity: 7.9 L / 7.6 L
• Recommended Cooling: Thermostatic control
• Ethanol Blend Limit: 10% maximum
• Gear Ratio: 1.75:1
• Gear Shift: Forward, Neutral, Reverse
• Shaft Length: 25" - 30" - 35"
• Degree of Tilt: 69°
• Degree of Trim: -3° through +16°
• Mounting Centers: 28.5"
• Steering: Integrated, electric actuation
• Steering Angle (maximum): 32° from center, either direction
• Warranty: Limited 3-Year Pleasure, 3-Year Government, 1-Year Commercial