Mercury 4 HP 4-Stroke Portable Outboard Motor

Ultra-Quiet 4-Stroke Performance, Excellent Fuel Efficiency & Integrated Fuel Tank

The Mercury 4 HP 4-Stroke Outboard Motor is an excellent choice for fishing, trolling, and recreational boating. Designed with a compact and portable configuration, this clean-running four-stroke outboard delivers quiet operation, smooth idling, and dependable performance without the smoke associated with traditional two-stroke engines. The engine combines 4-stroke efficiency with easy starting and straightforward controls, making it well suited for small boats, tenders, fishing boats, and other lightweight watercraft. Its integrated fuel tank, side-shift controls, shallow-water capability, and included propeller provide a convenient all-in-one propulsion solution. With 40% greater fuel efficiency than a comparable 2-stroke engine, a CARB three-star ultra-low-emissions rating, and built-in engine protection features, this Mercury outboard is designed to provide reliable performance while keeping operation clean and economical.

Key Features

Quiet, Clean-Running 4-Stroke Engine

The 4-stroke engine is designed for ultra-quiet operation, smooth idling, and smoke-free performance. It provides a more refined experience for anglers and recreational boaters, particularly when trolling or operating at low speeds.

4 HP of Reliable Marine Power

With a rated output of 4 horsepower and a full-throttle operating range of 4,500–5,500 RPM, the engine provides practical propulsion for compatible small boats and watercraft.

Improved Fuel Efficiency

Mercury's 4-stroke technology is stated to deliver 40% greater fuel efficiency than a comparable 2-stroke engine, helping extend operating time while reducing fuel consumption.

Integrated Fuel Tank

The motor features an integral 0.3-gallon fuel tank, providing a convenient self-contained fuel system and contributing to the motor's portable design.

Fuel Shut-Off Valve

A dedicated shut-off valve helps prevent fuel spillage when transporting or storing the outboard, adding convenience for portable use.

Easy, Reliable Starting

The engine incorporates a decompression system and electronic CD ignition to provide easier and more reliable manual starting.

Engine Protection Systems

Built-in protection features include:

• One-stage over-rev protection
• Low oil pressure warning system

These systems provide additional peace of mind by helping protect the engine during operation.

Full Forward-Neutral-Reverse Shifting

The side-mounted shift system provides convenient access to:

• Forward
• Neutral
• Reverse

This makes maneuvering around docks, fishing areas, and tight spaces easier.

Shallow-Water Drive

The motor provides six trim positions plus a shallow-water drive setting, allowing the operator to raise the motor when navigating shallower areas.

Tiller Steering

The tiller-style steering system provides direct control and is well suited to smaller boats where compact, responsive controls are preferred.

Propeller Included

A 3-blade 8-3/8-inch diameter × 7.0-inch pitch propeller is included, providing a ready-to-use propulsion setup.

Specifications

Engine Specifications

Specification	Details
Brand	Mercury
Horsepower	4 HP
Engine Type	4-Stroke, 2-Valve Push Rod
Full-Throttle RPM	4,500–5,500 RPM
Starting System	Manual with Decompression System
Ignition	Electronic CD Ignition
Cooling / Marine Design	4-Stroke Marine Engine
Exhaust System	Through Prop
Steering	Tiller
Gear Positions	Forward-Neutral-Reverse
Gear Ratio	2.15:1

Fuel System

Specification	Details
Fuel Tank Type	Integral
Tank Capacity	0.3 gallon
Recommended Fuel	87 Octane
Ethanol Compatibility	Up to 10% Ethanol
Fuel Shut-Off	Yes

Shaft & Mounting

Specification	Details
Shaft Length	15 inches
Shaft Configuration	Short Shaft
Trim Positions	6
Shallow-Water Drive	Yes

Propeller

Specification	Details
Propeller Included	Yes
Propeller Diameter	8-3/8 inches
Propeller Pitch	7.0 inches
Blade Configuration	3-Blade

Weight

Specification	Details
Dry Weight	57 lbs.

Engine & Performance

The Mercury 4 HP outboard is built around a 4-stroke, 2-valve push-rod engine designed for dependable marine performance. Its 4,500–5,500 RPM full-throttle operating range provides responsive power while maintaining the smooth characteristics expected from a modern four-stroke engine. The engine's clean-running design is particularly beneficial for fishing and trolling applications, where quiet operation and smooth low-speed performance are important.

Starting System

Starting is simplified by the combination of an electronic CD ignition system and decompression mechanism. The decompression system reduces the effort required during manual starting, while the electronic ignition helps provide reliable ignition for consistent starts.

Fuel Efficiency & Portability

One of the key advantages of this Mercury outboard is its combination of fuel efficiency and portability. The manufacturer description states that the 4-stroke design is 40% more fuel efficient than a comparable 2-stroke engine. The integrated 0.3-gallon fuel tank eliminates the need for a separate external tank for the supplied configuration, helping keep the installation compact and convenient. A fuel shut-off valve also helps reduce the possibility of fuel spillage during transport and storage.

Shifting & Maneuverability

The full Forward-Neutral-Reverse transmission is controlled through the side-shift system. This provides convenient directional control for launching, docking, fishing, and general recreational boating. The tiller steering configuration gives the operator direct control of the outboard, making it particularly suitable for smaller watercraft.

Trim & Shallow-Water Capability

The motor features six trim positions plus a dedicated shallow-water drive position. This allows the operator to adjust the motor's position according to operating conditions and raise it when traveling through shallow water. Proper trim adjustment can also help optimize handling and propulsion for different boat-loading and water conditions.

Emissions & Environmental Performance

The engine carries a CARB three-star ultra-low-emissions rating, reflecting its clean-running four-stroke design. Combined with its stated fuel-efficiency advantage over comparable 2-stroke engines, the Mercury 4 HP is designed to provide an efficient and environmentally conscious option for small-boat propulsion.

Engine Protection

The integrated protection systems help provide additional confidence during operation:

• One-stage over-rev protection helps protect the engine from excessive RPM.
• Low oil pressure warning alerts the operator to a potentially important lubrication condition.

These features are especially useful for recreational and fishing applications where dependable engine operation is essential.

Recommended Applications

The Mercury 4 HP 4-Stroke Outboard Motor is well suited for:

• Fishing boats
• Trolling
• Small boats
• Dinghies
• Tenders
• Recreational boating
• Auxiliary propulsion
• Low-speed cruising
• Shallow-water boating
• General small-watercraft use

Package Includes

The supplied product information indicates that the package includes:

• Mercury 4 HP 4-Stroke Outboard Motor
• 3-Blade Propeller
• Integrated Fuel Tank

Important Product Notes

• Horsepower: 4 HP
• Shaft: 15 inches
• Dry weight: 57 lbs.
• Fuel tank: 0.3 gallon integral tank
• Fuel: 87-octane gasoline, with up to 10% ethanol
• Gear positions: Forward, Neutral, Reverse
• Gear ratio: 2.15:1
• Trim: 6 positions plus shallow-water drive
• Propeller: 8-3/8″ diameter × 7.0″ pitch, 3-blade
• Starting: Manual with decompression system
• Steering: Tiller
• Exhaust: Through prop
• Emissions: CARB 3-Star Ultra-Low Emissions

Why Choose the Mercury 4 HP 4-Stroke Outboard?

The Mercury 4 HP 4-Stroke Outboard Motor offers a strong combination of quiet operation, fuel efficiency, portability, and dependable marine performance. Its clean-running four-stroke engine provides smooth idling without the smoke associated with traditional 2-stroke operation, while the integrated fuel tank keeps the installation compact and convenient. With easy manual starting, Forward-Neutral-Reverse shifting, six trim positions, shallow-water drive, over-rev protection, and a low oil pressure warning system, this outboard is designed for straightforward operation and dependable performance. For anglers, small-boat owners, and recreational boaters looking for an efficient portable motor, the Mercury 4 HP provides a practical and versatile solution.

• We currently ship within the United States only.
• Enjoy free standard shipping on all orders.
• Orders are processed within 1–2 business days.
• Estimated Total Delivery Time is 4–7 business days.
• Tracking information will be sent to your email within 24 hours after your order has been dispatched.
• For more information about our shipping process, please view our full Shipping Policy.

• Not satisfied? Return or exchange within 30 days.
• Items must be unused and in original condition.
• Damaged products are eligible for a refund or replacement.
• For more information about our return & refund process, please view our full Return & Refund Policy.

We’re able to offer competitive prices because we work directly with manufacturers, distributors, and trusted suppliers. We also purchase overstock, seasonal inventory, and discontinued models, which helps us provide brand-new, quality products at lower prices.