Carburetor Assembly for Tohatsu & Nissan 2.5HP and 3.5HP 2-Stroke Outboards; Mercury & Mariner 2HP–3.3HP 2-Stroke Replacement

Product Details

This aftermarket carburetor assembly is designed for selected Tohatsu and Nissan 2-stroke outboard motors rated at 2.5HP and 3.5HP, including listed M2.5, M3.5, NS2.5, and NS3.5 applications from the applicable model years. It also fits selected Mercury and Mariner 1-cylinder 2-stroke engines in the 2HP, 2.2HP, 2.5HP, 3HP, and 3.3HP ranges when the engine's original part number and serial-number range match the information below.

The assembly is listed as a replacement for several Tohatsu, Nissan, and Mercury references, including 3F0-03100-4, 3D5-03100-5, and 823040A1. Always compare the original carburetor, part number, model, year, and serial number before ordering.

• Complete replacement carburetor assembly for listed applications.
• Direct-replacement design for compatible engines.
• Silver zinc-alloy housing with marine-use corrosion-resistant construction.
• One carburetor assembly is included.

Part Number Matrix

Use the following references to compare the replacement with the carburetor currently installed on your engine.

Engine & Model Compatibility

Fitment depends on the complete model, year, stroke, original part number, and—where specified—the engine serial number. The tables below summarize the listed applications; they are not a substitute for checking the identification plate and original carburetor.

Tohatsu 2-Stroke Models

Nissan 2-Stroke Models

Mercury / Mariner 2-Stroke Models

For Mercury and Mariner applications, verify both the horsepower rating and the complete serial-number range before ordering.

Technical Specifications

Product Type

Carburetor assembly

Installation

Direct replacement for compatible applications

Fuel Type

Gasoline

Housing Material

Zinc alloy

Housing Color

Silver

Construction

Marine-use corrosion-resistant construction

Product Status

Aftermarket replacement; not an OEM component

What's in the Box

• 1 x Carburetor assembly

Installation Notes

1. Safety first: Turn the engine off, allow it to cool, shut off the fuel supply, and disconnect the battery where applicable.
2. Record connections: Before removal, note the routing and positions of the fuel lines, throttle linkage, and any other connected components.
3. Remove the old carburetor: Disconnect the fuel lines and linkages, then remove the mounting hardware and old carburetor.
4. Prepare the mounting surface: Clean the intake-manifold surface and install a suitable new gasket if required by the engine service manual.
5. Install the replacement: Position the carburetor and tighten the mounting hardware evenly to the manufacturer's specified torque.
6. Reconnect components: Reattach the fuel lines and throttle linkages to their original positions.
7. Check for leaks: Restore the fuel supply and inspect all connections before starting the engine.
8. Test the engine: Start the engine in a safe, well-ventilated area and adjust idle settings only as directed by the applicable service manual.

Troubleshooting & FAQ

Safety & Important Information

• Verify the engine model, year, horsepower, stroke, serial number, and original part number before ordering.
• Do not rely on horsepower alone to confirm compatibility.
• Fuel-system work should be performed with the engine cool and away from ignition sources.
• Professional installation is recommended when you are not familiar with marine engine fuel systems.
• This is an aftermarket replacement, not an OEM component.

About Sea Sierra

• Pro-Grade Standards — Marine replacement parts selected for dependable real-world service.
• Fast Global Fulfillment — Standard delivery options are available to most regions; availability and transit time are shown at checkout.
• Manufacturer-Direct Value — Practical replacement parts at competitive prices.