KENNESAW, Ga. -- Yamaha Marine announces its new F150 four-stroke outboard for 2004. The F150 satisfies the needs of anglers looking for quiet, fuel-efficient power for mid-sized boats.
Yamaha has traditionally used V6 powerheads for engines in this range. For the F150, Yamaha broke that tradition and instead uses a compact and lightweight Inline-4 powerhead. This all-new engine actually has a greater displacement than Yamaha's two-stroke V6 outboards with the same power rating - 2.7-liter vs. 2.6-liter - while weighing in at only 466 pounds.
"One of the most stunning visual clues that this is an all-new motor is the slimmer width of the powerhead when compared to its two-stroke counterpart," said David Grigsby, product manager of Yamaha's Marine Power Division. "The F150 is an ideal motor for single installation on boats from 17- to 22-feet and for dual installation on boats from 23- to 27-feet. Counter-rotating models are available in 25-inch shaft lengths for dual installations to keep the boat tracking true.
"While our four-strokes are popular with saltwater anglers, this F150 will find a home on just about any boat, including pontoons, deck, flats, deep V and offshore models."
The powerhead features lightweight forged pistons and specially heat-treated crankshaft and connecting rods for additional durability and strength. A flywheel dampener reduces crankshaft vibration for smoother operation and less wear on the engine's internal components. Gear case components are also stronger including the clutch, shift cam and specially heat-treated forged gears. In addition, water-sealed outer walls reduce engine noise.
The engine itself features a double-overhead cam design for greater valve timing control plus four valves per cylinder in Yamaha's Crossfire Valve System to provide clean, powerful combustion. A crankshaft offset by 10mm provides larger intake volume making way for the four tuned intake tubes coupled with a large-volume intake silencer to boost the torque in the low- to mid-RPM range for quick acceleration. The composite-made intake tubes and silencer help reduce overall weight of the motor. A blow-by gas reburning system removes any unburned fuel from the exhaust gases and routes it back into the fuel delivery system to be more-efficiently burned.
The large displacement and 4-to-1 exhaust system increase exhaust efficiency to enhance maximum power output while a 2:1 gear ratio provides strong acceleration.
To reduce engine noise as much as possible, the F150 features a labyrinth exhaust system and water-sealed outer walls.
Controlling all of this technology is the Engine Control Module (ECM) which receives input from six sensors placed around the engine. The ECM uses this data to calculate the precise fuel/air mixture to each combustion chamber depending on load and speed. The ECM also warns the operator of any impending problems, keeps the engine running if any sensors fail and allows service personnel to download diagnostic information and engine operating history onto a diagnostic system at a Yamaha dealership. The warning system includes overheat warning, over-rev prevention, low-oil pressure warning, neutral throttle limiter and start-in-gear prevention.
An over-cool prevention cooling system with a 60-degree Celsius thermostat maintains proper engine temperature for more fuel-efficient operation and additional durability.
Realizing the need to build cleaner-running outboards, Yamaha built the F150 to meet and exceed the 2006 Federal EPA emission standards and the 2008 California Air Resources Board (CARB) emission standards years ahead of time. In fact, the F150 attains a 3-Star Ultra Low Emissions rating from CARB, the highest rating CARB bestows on outboards.
An automatic oil-draining device drains the remaining oil from the oil filter to prevent oil spillage during oil filter changes. The oil stick tube extends down to the bottom of the oil pan allowing for better precision when checking oil levels and allowing the use of a suction tool for quick and easy oil changes.
Available with a 20- or 25-inch shaft length, the F150 features a wide-range power trim and tilt that goes from -4 degrees for quick hole shots to +16 degrees to improve top-end performance. The F150 can also be raised and lowered while the boat is on the trailer with the conveniently located pan-mounted tilt switch. On counter-rotation models, the pan-mounted trim switch can be located to the outward side for ease of use.
An electric starter adds user convenience, and PrimeStart provides the proper fuel mixture for all weather conditions to ensure the motor starts quickly the first time the key is turned on. Temperature-controlled water cooling ensures proper engine temperature at all times for consistent performance and long trouble-free engine life. Boaters can visually confirm the water pump is operating with the pilot water discharge.
The F150 features a marine alternator located beneath the flywheel on top of the engine where it is up and away from any water intrusion. The high-output alternator generates 35 amps while under way to keep the battery charged, allowing electronics or livewell pumps to run all day. A strong 2:1 gear ratio combined with the large-displacement four-cylinder engine's torque is able to move even large boats through heavy chop.
Another strength of the new F150 is its level of corrosion fighting measures. A front-mounted freshwater flushing device offers convenient engine flushing from the dock or the boat by attaching to a standard garden hose without any tools. The motor does not need to be running to flush the engine. Protection from the elements comes from the ACP-221 paint application, a technologically advanced process featuring multiple layers of tough primer and finish coats. Stainless steel components battle internal corrosion while all aluminum components that contact the water are made from Yamaha's tough YDC 30 aluminum alloy. Zinc anodes in the powerhead, mid section and lower unit sacrifice themselves to protect other metal components from corrosion.
A super-tight cowling and water-draining air intake ducts route any water away from the engine and drain it out the bottom cowling while a large water-separator keeps any water in the fuel from entering into the vapor separator. These measures combine to enhance engine durability and corrosion protection.
Like all Yamaha four-stroke outboards, the new F150 is backed by Yamaha's Three-Year Factory Limited Warranty at no extra cost.