Yamaha Outboards 90HP Jet | F90JB

Yamaha F90JB 90 HP Four-Stroke Outboard: The Ultimate Jet Drive for Shallow Water Adventures

The Yamaha Outboards 90HP Jet | F90JB.

Are you an angler or boater who thrives on exploring challenging waters?

Perhaps you frequently navigate shallow rivers, rocky shoals, or areas filled with debris where a traditional propeller risks damage. Therefore, you need an outboard motor designed to handle these unique conditions.

Shop the Yamaha F90JB 90HP (65HP Jet) 4-stroke jet drive outboard with 25″ transom, electric start, remote control, EFI, & Power Trim & Tilt. Features 161kg 1.8L 4-cylinder SOHC design, 35-amp charging, & VTS. Ideal for shallow water, rivers, rocky areas. Powerful & efficient.

The Yamaha F90JB 90 HP Four-Stroke Jet Drive Outboard is your solution. It offers robust power at the powerhead (90 HP) with the distinct advantage of a jet drive. This means unparalleled access to areas normally out of reach.

Specifically, the F90JB combines significant power with effortless electric starting and precise remote control. Additionally, it features Power Trim & Tilt and advanced Electronic Fuel Injection (EFI). Ultimately, this makes it an outstanding choice for boaters demanding top performance in extreme shallow-water conditions.

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Understanding the F90JB Model Code

The “JB” in the Yamaha F90JB model designation clearly defines its key characteristics.

The “J” for Jet Drive

First, the “J” signifies that this is a Jet Drive model. This is the most crucial distinction. The F90JB uses an impeller inside a housing to create thrust instead of a conventional propeller. Consequently, this design allows the boat to operate in much shallower water. It avoids the risk of damaging a propeller or lower unit, making it ideal for rocky rivers, sandbars, and debris-filled areas.

The “B” for Remote Control

Next, the “B” in F90JB, often used in newer model designations, indicates that the engine is configured for Remote Mechanical Control. This means you operate the engine from a helm station. Mechanical throttle and shift cables provide precise control. This setup usually includes a remote key switch.

Thus, the F90JB is engineered for boaters. It combines the power of a 90 HP engine (at the powerhead) with the advantages of a jet drive. It offers the convenience of electric starting and precision remote control.

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Why the Yamaha F90JB Stands Out: Key Advantages

For boaters prioritizing access to very shallow waters, strong power, and the peace of mind of a prop-free design, the Yamaha F90JB truly excels.

Powerful 1.8L Engine with Jet Thrust

The F90JB uses a robust 1.8-liter (1832cc) in-line four-cylinder, 16-valve, SOHC four-stroke engine. This is the same powerful platform as the F90 propeller model, providing 90 horsepower at the powerhead. However, a jet pump inherently involves some mechanical losses. Therefore, the equivalent thrust at the pump is approximately 65 horsepower. This large displacement and multi-valve design ensures strong low-end torque and impressive mid-range acceleration. It delivers excellent performance for jet applications.

Lightweight and Agile Design

Despite its power, the F90JB benefits from Yamaha’s innovative SOHC design. This design actuates four valves per cylinder with a single overhead camshaft. This significantly reduces weight compared to DOHC engines of similar displacement. Weighing about 161 kg (354 lbs), including the jet pump, the F90JB offers an excellent power-to-weight ratio. This ensures it’s powerful yet manageable for mounting. It also provides better overall boat balance, which is vital for shallow-draft boats.

Jet Drive: Conquer Shallow Waters

The Jet Drive system is the F90JB’s defining feature. With no gearcase or propeller extending below the hull, this motor lets you navigate around or over obstructions. Think of rocks, logs, or sandbars that would stop a conventional, propped outboard. In short, it allows you to explore “off-road” on the water. This opens up new fishing spots or lets you navigate swiftly flowing rivers with confidence.

Electronic Fuel Injection (EFI)

A key feature is its Multi-Point Electronic Fuel Injection (EFI) system. This precise system, managed by an Engine Control Module (ECM), accurately meters fuel to each cylinder. Consequently, you get dependable, “first-time, every-time” hot and cold starts. Furthermore, it ensures superior fuel efficiency, smoother acceleration, and excellent throttle response across the entire RPM range.

Effortless Starting and Trim

The electric start system offers unmatched convenience. No more manual pull-starting; a simple turn of a key brings the engine to life. This makes operation much easier, especially in unpredictable conditions. Additionally, the Power Trim & Tilt system allows instant, push-button adjustment of the jet nozzle angle. This optimizes boat performance, helps navigate extremely shallow water (by tilting up), and simplifies trailering.

Precision Remote Control

The F90JB is designed for remote mechanical control from your helm station. This setup provides precise and comfortable control over steering, throttle, and jet thrust. Thus, it’s ideal for boats with steering consoles or side consoles where direct tiller operation isn’t practical. This setup gives you clear forward visibility and a more integrated boating experience. Moreover, it’s compatible with Yamaha’s optional Digital Network Gauges (e.g., Command Link®). These gauges provide real-time engine data, fuel management, and other vital information. This enhances control and efficiency and offers NMEA2000 compatibility.

Clean, Smooth, and Quiet Operation

The F90JB’s 1.8-liter four-cylinder, 16-valve SOHC engine runs exceptionally quiet, smooth, and fuel-efficiently. It also produces ultra-low emissions. It holds a CARB 3-Star Rating, indicating superior environmental performance. Moreover, features like its 5mm offset crankshaft (reducing internal friction), single bore throttle body, improved engine rigidity, redesigned muffler, and intake silencer all contribute to its remarkably quiet operation and reduced vibration, even at high RPMs. Its Labyrinth Exhaust System further muffles exhaust noise.

High-Output Charging Power

The F90JB features a powerful 35-amp alternator output (12V). This provides ample power for onboard electronics and reliably charges your battery. This is a crucial feature for modern boats with many accessories. It ensures your battery is always ready, even after extended periods of idling or running multiple devices. You get up to 28 amps available at just 1000 RPM.

Legendary Durability and Corrosion Protection

As with all Yamaha outboards, the F90JB boasts exceptional durability. It features a robust design with superior corrosion protection. This includes Yamaha’s unique YDC-30 aluminum alloy, a 5-stage Phaze Five™ anti-corrosive paint process, and multiple sacrificial anodes (extra-large, strategically placed). High-quality marine-grade stainless steel components are also used. All these elements are designed to withstand harsh marine environments. They ensure years of reliable service. Furthermore, its pressurized oiling system minimizes engine wear for extended engine life. Plus, a freshwater flushing system allows for easy rinsing of salt and debris without running the engine, which greatly reduces corrosion, especially for jet drives.

Variable Trolling RPM Control (VTS®)

The F90JB also offers Variable Trolling RPM Control (VTS®). This feature lets you precisely adjust trolling speeds in 50-RPM increments. This is typically done between 550 and 1000 RPM using an optional Digital Network Tachometer or a remote VTS switch. This is invaluable for anglers. It allows fine-tuning lure presentation for different species or conditions, enabling ultra-slow trolling.

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Core Features: Yamaha F90JB 90 HP Four-Stroke Jet Drive Outboard

Here’s a concise overview of the key features that make the Yamaha F90JB an outstanding choice:

Engine & Performance

• 90 HP Powerhead / 65 HP Jet Pump Output: Strong power for propulsion in shallow water.
• 1.8L Four-Cylinder, 16-Valve SOHC Engine: Large displacement, compact, and efficient.
• Electronic Fuel Injection (EFI): Reliable starts, optimal fuel economy, excellent throttle response.
• Variable Trolling RPM Control (VTS®): Fine-tune trolling speeds from 550-1000 RPM.
• Prime Start™ System: Ensures instant cold starts.
• Offset Crankshaft: Reduces internal friction for better efficiency.

Propulsion & Control

• Jet Drive Lower Unit: Propeller-free operation for extreme shallow water access.
• Electric Start: Effortless ignition.
• Remote Mechanical Control: Precise steering, throttle, and jet thrust from the helm.
• Power Trim & Tilt: Easy adjustment of jet nozzle angle for performance and shallow water.

Design & Durability

• 25-inch Transom Fit: Optimized for boats with higher transoms requiring a jet drive.
• Competitive Weight (161 kg / 354 lbs): Excellent power-to-weight ratio for a jet drive.
• High-Output 35-Amp Alternator: Powers electronics and charges batteries efficiently.
• Legendary Yamaha Reliability & Corrosion Protection: Built to withstand harsh marine environments.
• CARB 3-Star Rating: Ultra-low emissions.
• Watertight Cowling: Protects internal components from water intrusion.

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Ideal Applications for Your Yamaha F90JB Jet Drive Outboard

The Yamaha F90JB is the perfect power solution for boats that must operate in challenging, shallow, or debris-filled waters.

Shallow Draft and River Boats

This engine is specifically ideal for custom shallow-draft boats, aluminum river boats, and similar vessels. It can even serve as auxiliary power for airboats. Ultimately, it excels in navigating rocky rivers, sandbars, and areas with submerged obstacles. Its prop-free design eliminates common damage risks.

Jon Boats and Flat-Bottom Skiffs

Similarly, for larger jon boats or flat-bottom skiffs, it’s perfect. These boats are often used for fishing or hunting in marshlands, skinny creeks, or shallow lakes. The F90JB provides both power and shallow-water capability.

Commercial and Utility Use

For specific commercial operations or utility boats, the F90JB offers a reliable solution. This includes environmental surveys or rescue operations in flooded areas, where access to very shallow or debris-laden areas is critical.

Accessing Remote Fishing Spots

Serious anglers will find the F90JB invaluable. It allows them to reach remote fishing spots that are otherwise inaccessible to propeller-driven boats.

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Yamaha Outboards 90HP Jet | F90JB Commitment to Quality and Performance

Choosing a Yamaha F90JB is more than just buying an outboard motor. You are investing in meticulously engineered marine equipment. It’s designed for impressive power, class-leading efficiency, effortless electric starting, and precise remote control. Furthermore, it boasts long-term reliability even in the most challenging environments.

Yamaha’s decades of innovation and craftsmanship are evident in every aspect of the F90JB. This ranges from its smooth, quiet, four-cylinder operation to its outstanding fuel economy and renowned durability. Ultimately, the F90JB embodies Yamaha’s promise. It delivers a superior boating experience. It ensures peace of mind and countless hours of adventurous, reliable performance. This holds true even when navigating the “off-road” of marine environments.

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Technical Specifications Yamaha Outboards 90HP Jet | F90JB (Approximate – Always Verify with Official Yamaha Resources for the specific model year)

• Model Name: F90JB
• Engine Type: 4-Stroke, SOHC, In-line 4-Cylinder, 16-Valve
• Horsepower (Powerhead): 90 HP
• Horsepower (Pump Output): 65 HP @ 5500 RPM (Jet Drive rating)
• Displacement: 1832 cc (1.8L / 111.8 ci)
• Bore x Stroke: 81.0 mm x 88.9 mm (3.19 x 3.50 in.)
• Full Throttle RPM Range: 5000 – 6000 RPM
• Fuel Induction System: Electronic Fuel Injection (EFI)
• Starting System: Electric with Prime Start™
• Ignition System: TCI Microcomputer
• Alternator Output: 35 Amps (12V) with Rectifier Regulator (28A at 1000 RPM)
• Lubrication System: Wet Sump (pressurized oil delivery system)
• Engine Oil Capacity: 3.2 L (3.0L with/without oil filter exchange)
• Gear Ratio: Direct Drive (Jet Pump)
• Gear Shift: F-N-R (Forward, Neutral, Reverse)
• Shaft Length Fit: Designed for 25-inch transoms
• Trim & Tilt System: Power Trim & Tilt
• Recommended Fuel: Regular Unleaded (Minimum Pump Octane 87)
• Recommended Fuel Filtration: Yamaha 10-Micron Fuel/Water Separating Filter (external, recommended)
• C.A.R.B. Rating: 3-Star (Ultra Low Emission)
• Exhaust: Through Jet Nozzle
• Weight (Dry): Approximately 161 kg (354 lbs) (including jet pump assembly)
• Steering: Remote Mechanical Control (35° from center, either direction)
• Standard Features: Electric Start, Power Trim & Tilt, EFI, Freshwater Flushing System, Variable Trolling RPM Switch (VTS®) compatibility, Robust Corrosion Protection (YDC-30 alloy, 5-stage paint process, extra-large anodes), Offset Crankshaft, Watertight Cowling with Intake Air Drain System, Compatible with Yamaha Command Link® Digital Gauges (optional), NMEA2000 compatibility.
• Typical Color: Yamaha Gray

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Are you ready to access the inaccessible with a powerful, versatile, and dependable 90 HP (powerhead) jet-drive outboard? It comes with the convenience of electric start, Power Trim & Tilt, and precise remote control. Invest in the Yamaha F90JB 90 HP Four-Stroke Jet Drive Outboard Motor today. Discover the freedom and excitement of shallow-water navigation. Experience quiet, smooth, and highly reliable operation, all backed by Yamaha’s trusted quality. Ultimately, make your adventures on the water truly limitless.