Honda BF40D4LHA 40HP 20" Outboard Engine
Reliable Compact 4-Stroke Power for Everyday Boating
The Honda BF40D4LHA 40HP 20-inch Shaft Outboard Engine is a lightweight, fuel-efficient, and highly reliable marine engine designed for small to mid-size boats, fishing boats, inflatables, and utility craft. Built with Honda’s advanced 4-stroke engineering, this 3-cylinder outboard delivers smooth power delivery, excellent fuel economy, and quiet operation for both freshwater and saltwater use.
With its 20-inch (long shaft) configuration, the BF40D4LHA is ideal for boats with standard transoms, ensuring proper propeller depth for stable performance in varied water conditions. It combines Honda’s proven durability with modern electronic fuel injection (EFI) technology for easy starting and responsive throttle control.
Engine Performance & Technology
The BF40D4LHA uses a 808cc inline 3-cylinder 4-stroke engine engineered for balanced performance and efficiency. It delivers strong mid-range torque, making it ideal for cruising, fishing, and light commercial use.
Honda’s PGM-FI (Programmed Fuel Injection) system ensures precise fuel delivery, resulting in:
- Quick and reliable cold starts
- Smooth acceleration
- Improved fuel efficiency
- Reduced emissions
The engine also features Honda’s BLAST™ (Boosted Low Speed Torque) technology, which enhances hole-shot performance by improving air-fuel mixture during rapid acceleration. This gives the BF40 strong takeoff power for its class.
Design & Durability
The BF40D4LHA is built with Honda’s marine-grade corrosion protection system, making it suitable for both saltwater and freshwater environments. Its compact and lightweight design improves boat balance and handling while reducing overall transom stress.
Key durability features include:
- Multi-layer anti-corrosion coating system
- Freshwater flush port for easy maintenance
- Heavy-duty gearcase for reliable propulsion
- Engine alert system for protection monitoring
Shaft & Installation Advantage
The 20-inch shaft (L model) is designed for:
- Standard transom boats
- Aluminum fishing boats
- Fiberglass runabouts
- Utility and workboats
This ensures optimal propeller immersion, preventing cavitation and improving thrust stability in moderate water conditions.
Key Features
- 40HP efficient 3-cylinder 4-stroke marine engine
- 808cc displacement for smooth performance
- Electronic Fuel Injection (PGM-FI) system
- BLAST™ technology for improved low-speed torque
- 20-inch long shaft (L model)
- Electric start system
- Gas-assisted tilt for easier handling
- 17A charging system for onboard electronics
- Lightweight compact design for easy installation
- Excellent fuel economy and low emissions
- Corrosion-resistant marine construction
- Engine alert and protection system
- Quiet and smooth operation
Technical Specifications
| Specification |
Details |
| Engine Model |
Honda BF40D4LHA |
| Engine Type |
Inline 3-Cylinder 4-Stroke |
| Horsepower |
40 HP |
| Displacement |
808 cc |
| Fuel System |
PGM-FI Electronic Fuel Injection |
| Bore x Stroke |
70 mm × 70 mm (approx.) |
| Maximum RPM |
5000 – 6000 RPM |
| Cooling System |
Water-cooled (thermostatic) |
| Ignition System |
Digital CDI |
| Starting System |
Electric Start |
| Steering |
Remote / Tiller (variant dependent) |
| Shaft Length |
20 inches (Long Shaft) |
| Alternator Output |
17A |
| Trim & Tilt |
Gas-assisted tilt |
| Fuel Type |
Unleaded gasoline |
Applications
- Small fishing boats
- Aluminum boats and jon boats
- Inflatable boats (RIBs)
- Dinghies and tenders
- Light utility and work boats
- Inland and coastal recreational boating
Advantages
- Excellent fuel efficiency for long trips
- Strong low-end torque with BLAST™ system
- Smooth and quiet 4-stroke operation
- Easy starting with EFI technology
- Lightweight and compact design
- Reliable Honda marine durability
- Low maintenance requirements
- Ideal balance of power and economy for 40HP class
