Yamaha F115LB 115HP 4-Stroke Outboard – 20in Shaft, EFI
Steering stays direct, Yamaha F115LB channels 115 horsepower. A 20-inch shaft fits standard transoms. The block runs EFI technology. The layout favors easy servicing over a season of use.
- Rated at 115 horsepower
- 20-inch shaft for most transoms
- EFI fuel delivery system
- Straightforward to service and maintain
- 20-inch shaft, standard fit
Description
Bass boat captains craving explosive acceleration trust the Yamaha F115LB to dominate morning tournament runs. The 1832cc 16-valve DOHC block utilizes precise Electronic Fuel Injection to atomize gas perfectly, pushing loaded 18-foot fiberglass hulls across choppy bays effortlessly. Verifying your exact transom height guarantees this 115hp 20 inch shaft outboard fits securely without causing excessive lower unit hydrodynamic drag.
Maintain optimal running attitudes in rough water instantly by engaging the hydraulic power trim and tilt system to tuck the gearcase inward. You push the bow down fast from the console switch to slice through morning chop safely. Engineers cast the 171 kg midsection using specialized anti-corrosion marine aluminum. This physical barrier stops galvanic decay when repowering performance aluminum boats in high-salinity coastal environments.
Key Features of Yamaha F115LB
- 1.8-Liter Inline-Four Block: Breathes massive volumes of clean air efficiently, generating 115 horsepower effortlessly to lift heavy fiberglass hulls onto plane.
- 20-Inch Standard Shaft: Matches standard high-performance transoms perfectly, keeping the gearcase profile tight to maximize top-end running speeds.
- Electronic Fuel Injection: Calculates precise fuel requirements continuously, eliminating carburetor hesitation and ensuring crisp throttle response across the 5800 RPM band.
- Hydraulic Power Trim: Adjusts the running angle dynamically via a console switch, optimizing bow attitude across aggressive offshore swells.
- Remote Mechanical Control: Accepts standard mechanical cables directly from your forward helm, integrating flawlessly with classic steering consoles.
- 35-Amp Charging Alternator: Outputs constant electrical current while running, keeping deep cycle batteries topped off for commercial aerators and navigation lights.
- 2.15:1 Gearcase Ratio: Spins aggressive high-pitch propellers efficiently, translating inline-four torque directly into forward vessel momentum.
- Turn-Key Electric Start: Ignites the block instantly via your forward ignition switch, providing car-like starting reliability in freezing weather.
- Anti-Corrosion Finish: Blocks severe galvanic decay physically, protecting the aluminum powerhead block across decades of daily saltwater exposure.
- Clean Four-Stroke Combustion: Eliminates messy two-stroke oil reservoirs, keeping your bilge completely clean while meeting strict clean water standards.
Why Choose Yamaha F115LB
Choosing this specific engine limits installation entirely to 20-inch tall transoms rigged with standard mechanical forward steering wheels. You cannot operate this via a tiller handle safely. Correcting your rigging geometry is a mandatory step when replacing older mechanical outboards.
- Measure the vertical distance from your top transom edge to the keel bottom.
- Install corresponding mechanical control cables sized exactly for your specific boat length.
- Keep coastal waters clean by running highly regulated four-stroke engine configurations.
Ideal Application and Vessel Fitment
This 20-inch remote-steered outboard excels on heavy aluminum bass boats, mid-sized center consoles, and 17-19ft fiberglass hulls carrying heavy payloads. By integrating a proven 1832cc displacement block with standard mechanical cable controls, the engine acts as an incredibly reliable mechanical workhorse for serious boaters. The 20-inch shaft ensures the center of gravity remains low, making this mechanical steer 115hp outboard an absolute necessity for fast bay fishing and heavy passenger hauling.
Warranty, Support and Maintenance
Authorized recreational operation receives a 3-Year Pleasure Warranty alongside exceptional factory support. Registered commercial applications fall under a strict 1-Year Commercial Warranty with zero corrosion coverage applied to the block. Scheduled maintenance requires replacing gearcase lubricants and changing oil filters at manual-specified intervals. Always save all physical service records. Your engine serial number acts as the only way to source exact genuine replacement parts. For product details and order support, Mulmotor offers assistance before your purchase is placed.
Yamaha F115LB Specs
| Brand | Yamaha |
| Full Model Code | F115LB |
| Engine Type | In-line 4-Cylinder, 16-Valve DOHC |
| Displacement | 1.8 Liters (1832 cc) |
| Horsepower | 115 HP @ 5800 RPM |
| Fuel Induction | Electronic Fuel Injection (EFI) |
| Alternator Output | 35 Amps |
| Gear Ratio | 2.15:1 |
| Shaft Length | L: 508 mm (20 in) |
| Dry Weight | 171 kg (377 lbs) |
| Starting & Steering | Electric Start & Remote Control |
| Trim/Tilt Method | Power Trim and Tilt |
| Standard Warranty | 3-Year Pleasure / 1-Year Commercial |
| Application | Bass Boats, Pontoons, Mid-size Center Consoles |















Reviews
There are no reviews yet.