Yamaha Four Stroke High Power

 
Yamaha's most powerful four strokes yet. Whisper quiet. Smooth running. Clean burning. Incredible fuel efficient. And rock-solid reliable.  Year after Year.
 

F250 Exclusive Features & Benefits
Variable Camshaft Timing on the new F250. The ECM (Engine Control Module) varies camshaft timing based on engine rpms, maximizing intake and exhaust efficiency. The result? Optimal combustion, greater volumetric efficiency - and a full 16% gain in torque in the 2000-3500 rpm range, where you really need it. Electronically-Controlled Single Throttle Valve precisely controls the air flow through the surge tanks in to the long tube intake tracks. The air silencer box reduces intake air noise for whisper quiet operation. The long tube intake tracks are tuned to increase air flow which boosts low end and midrange torque and performance.
Electronic Multi-Port Fuel Injection.  6 individual fuel injectors provide the precise amount of fuel for each individual cylinder. Optimal fuel atomization provides better combustion, further enhancing performance and fuel economy. Exhaust Pressure Reduction System reduces exhaust pressures while cooling the hub on the propeller. This process increases hp output while simultaneously increasing propeller durability. Another Yamaha innovative performance and reliability feature.
Large Diameter Intake and Exhaust Valves. The intake tracks are engineered to deliver the air and fuel more directly into the combustion chamber. This design allows additional space for the intake and exhaust valves to have an increased diameter which greatly increases volumetric efficiency. The intake valves also have larger valve lift for increase top end performance.
F225/F200 Exclusive Features & Benefits
Long Tube Intake Tracks are precision-tuned to maximize air velocity, delivering added low-end and midrange torque. Inside Track Fuel Injection positions individual fuel injectors on the inward side of each intake track, saving space and keeping electrical wiring away from the cowling latches.
Common High Power Features & Benefits
Yamaha's Award-Winning Innovation continues to revolutionize four stroke technology. Single Belt Drive System uses fewer moving parts and is simple in design for long term durability. The automatic belt tensioners keep the proper belt tension avoiding adjustments for added convenience. High Output Alternator produces 18 amps at 600 rpms and 38 amps at 1000 rpm to help keep batteries charged while trolling and an amazing 45 amps (46 amps on F250) from 2500 rpms to W.O.T. for today's use of an array of marine electronics. In-Bank Exhaust - Another Yamaha first. We reversed the conventional four stroke configuration, allowing space for the exhaust to exit between the V-block downward for a more compact design. The 24-Valve Double Overhead Cam uses 4 valves per cylinder for maximum power, fuel efficiency, and reliability. Sure-Seal Tri-Latches seal the cowl tight against water and debris. Compact 60° V6 Cylinder Block was conceived as a marine engine
in every detail, not adapted from an automotive design. Yamaha's Exclusive ACP-221 Paint Process provides a tough, 5-layer barrier against corrosion. It’s a key part of our renowned Ultimate Corrosion Protection System that’s standard on all Yamaha High Power Four Stroke engines. Yamaha Four Strokes blend fuel economy with power and performance from 2.5 hp all the way to the F350 V8! Every Yamaha Four Stroke is protected by our 3-Year Limited Warranty for pleasure use. Yamaha's Four Strokes meet all Federal EPA emission requirements. Our entire four stroke line-up (except the F4 and F2.5) has earned a California C.A.R.B. three-star rating for ultra-low emissions. Our F4 and F2.5 models have earned a two-star rating for very low emissions.
Extended Trim range delivers better acceleration to plane and top end speed. The tilt range is a full 70° for tilting the engine above the waterline.
Freshwater Flush Device allows you to flush the engine without running it, for added convenience and long-engine life. Yamaha is dedicated to helping create a cleaner environment through advances in outboard technology.

4 STROKE SPECS IN PDF

YAMAHA FOUR STROKE HIGH POWER INFO