Updated: 05 Jul 2026

10 Best 4 stroke outboard engines of 2026

Updated: 05 Jul 2026

#1

Best Choice

NURSIA 30HP Outboard Motor, 4-Stroke Boat Engine with Tiller Handle, Navy Blue

9.9

Nursia

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Main highlights

POWERFUL ENGINE: NURSIA 30HP four-stroke outboard motor delivers reliable and consistent power for a smooth boating experience.

FOUR-STROKE TECHNOLOGY: The four-stroke engine design provides improved fuel efficiency and quieter operation compared to two-stroke motors.
#2

Best Value

AIVWUMOT Carburetor 3BJ-03100-0 Compatible with Tohatsu 20HP (2009 and Newer) 4 Stroke Outboard Engine Motor MFS20C

9.8

AIVWUMOT

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Main highlights

【Warranty】1 Year

【Part Number】3BA-03133-0 3BA031330

【Application】Compatible with Tohatsu 20HP (2009 and Newer) 4 Stroke Outboard Engine Motor MFS20C
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#3

Mercury/Mariner 4-90HP Carburetted 4-Stroke Outboard Engine Manual

9.5

Clymer

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Main highlights

Item Package Weight - 3.39291421218 Pounds

Item Package Quantity - 1

Item Package Dimension: 10.9055117999L x 8.3858267631W x 0.6692913379H inches
#4

Gulf Western Outboard TC-W3 Two Stroke Marine Engine Oil 4 litre

9.4

Gulf Western Oils

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Main highlights

Minimise spark plug fouling and is a low smoke formulation

High performance synthetic two stroke engine oil

Designed for use in water cooled outboard engines
#5

Outboard Engines 2E (PB): Maintenance, Troubleshooting, and Repair, Second Edition: Maintenance, Troubleshooting, and Repair

9.3

International Marine Publishing
#6

Boat Motor 68T-85540-00 C.D.I CDI Unit Assy for Yamaha 4-Stroke Outboard Engine 8HP 9.9HP

9.2

SouthMarine

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Main highlights

Replaces Part OEM Number#: 68T-85540-00

Engine: 8HP 9.9HP

Engine Position: Outboard
#7

Poweka 35-16248 in-line Fuel Filter for Mercury 2-Cycle 4-Stroke 4-30HP Outboard Engine,Fit for Tohatsu Nissan 369-02230-0 369022300M,

9.0

Poweka

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Main highlights

Part Number: Replace Tohatsu / Nissan 369-02230-0 369022300M and Mercury 35-16248.Yamaha Outboard 646-24251-02-00, 646-24251-01-00 and Sierra 18-7713

Fits these Tohatsu outboard models: M4 M5 M6 M6 M8 M9.8 MFS4 MFS5 MFS6 MFS9.8 MFS15 MFS18 MFS20C MFS25A MFS30A

16248 Boat Motor In-line Fuel Filter for Mercury and Mariner 2-Cycle and 4-Stroke Outboards
#8

Outboard Engine Flush Kit for Yamaha - Boat Motor Quick Connect Flush Adapter for Yamaha Offshore, VMax SHO & XTO Offshore All 4 Stroke Outboard Engines, Motor Ranging from 8HP-425HP (Excluding 115HP)

8.9

XCWT

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Main highlights

Quick Connect Adapter: The outboard engine flush kit for Yamaha features a quick connect flush hose adapter, allowing for easy and convenient attachment to the engine's flushing port, saving time and energy. The flush kit is a more ergonomic approach than unscrewing the Yamaha OEM adapters and worrying about dropping O-rings into the water.

Easy to Use: The flush kit worked with Yamaha outboard motor only needs to connect the adapter to the engine's flushing port, attach a garden hose, and turn on the water supply to start the flushing process. The outboard engine flusher kit ensures thorough flushing of the engine's internal components, including the cooling system, to remove salt, sand, and other debris. Regularly flushing outboard motor helps prevent corrosion and extends your Yamaha boat engine's lifespan.

Convenient Maintenance: The grey flush adapter's built-in check valve restricts water flow unless hooked up to the outboard engine. Boat owners don’t have to make repeated trips to the faucet to turn the water on and off or kink the hose with one hand while attempting to ready the flush port with the other.
#9

EMSea 2x Carburettor Gasket Compatible with Honda 40HP 50HP 4-Stroke Outboard Engine BF40A BF50A, 16221-ZW4-000

8.7

EMSea

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Main highlights

Seal Support: Helps form a tight seal in the carburettor system to assist with consistent engine performance.

OEM Fitment: Matches original part number 16221-ZW4-000 for accurate and straightforward replacement.

Engine Compatibility: Compatible with Honda 40HP and 50HP 4-stroke outboard engines including BF40A and BF50A models.
#10

Cryfokt Outboard Motor Quick Connect Flush Kit, Boat Engine Flush Kit Outboard for PWC 4 Stroke Watercraft Marine Adapter

8.6

Cryfokt

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Main highlights

Quick and Easy Installation: The user friendly design of this kit allows for fast connection and disconnection, eliminating the need for complex tools or professional help when flushing your engine.

Complete Kit Components: This jet boat flush kit includes a slide valve and quick connector (hose adapter), providing an efficient method to flush your outboard engine quickly.

Broad Compatibility: The engine flush kit replacement for PWC's (except for GTS 99, 00), replacement for 4 stroke motorboat, ensuring versatility across your marine equipment.