Carburetor Assembly Set – Fits Yamaha 90HP (Replaces 6H1-14301-04-00, 6H1-14302-02-00, 6H1-14303-05-00)

Product Details

This Carburetor Assembly Set – Fits Yamaha 90HP (Replaces 6H1-14301-04-00, 6H1-14302-02-00, 6H1-14303-05-00) is designed for Yamaha 90HP 2-stroke outboard engines. The three-piece carburetor set includes top, middle, and bottom assemblies engineered to deliver reliable fuel atomization and throttle response across the complete carburetor bank.

This aftermarket assembly directly replaces OEM part numbers 6H1-14301-04-00 (top), 6H1-14302-02-00 (middle), and 6H1-14303-05-00 (bottom), offering complete carburetor bank replacement in a single package.

• Aluminum alloy construction for durability and long-term performance
• Lightweight design simplifies installation and handling
• Complete three-carburetor set for full bank replacement

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Engine & Model Compatibility

Confirm your engine model/year in the table below.

Technical Specs

Item Type

Outboard boat carburetor assembly set

Material

Aluminum alloy

Weight

Approx. 1945g / 68.6oz

Configuration

3-piece set (top, middle, bottom)

OE Number

6H1-14301/14302/14303

What's in the Box

• 3× Carburetor (top, middle, bottom assemblies)

Installation Notes

1. Disconnect the battery and fuel supply before beginning work.
2. Remove the engine cowling and locate the existing carburetor bank.
3. Disconnect throttle linkages, fuel lines, and choke cables from each carburetor.
4. Unbolt the old carburetors from the intake manifold, noting the position of each unit (top, middle, bottom).
5. Clean the manifold mating surfaces and inspect for cracks or damage.
6. Install new gaskets on each carburetor flange.
7. Mount the new carburetors in the correct order: top (6H1-14301-04-00), middle (6H1-14302-02-00), bottom (6H1-14303-05-00).
8. Torque mounting bolts evenly to manufacturer specifications.
9. Reconnect fuel lines, throttle linkages, and choke cables, ensuring all connections are secure.
10. Reconnect the battery and open the fuel supply.
11. Prime the fuel system and check for leaks before starting the engine.
12. Start the engine and adjust idle mixture and synchronization as needed per service manual.

Troubleshooting & FAQ

How do I know which carburetor is top, middle, or bottom?

The carburetors are typically labeled or differentiated by part number. Top is 6H1-14301-04-00, middle is 6H1-14302-02-00, and bottom is 6H1-14303-05-00. Refer to your engine's service manual or original carburetor positions for confirmation.

Can I replace just one carburetor instead of all three?

While individual replacement is possible, replacing the entire set ensures uniform performance and fuel delivery across all cylinders. Mismatched carburetors can cause rough running and poor throttle response.

Do I need to synchronize the carburetors after installation?

Yes. After installation, synchronize the carburetors to ensure even airflow and fuel mixture across all cylinders. Use a synchronization tool or follow your service manual's procedure for best results.

What are signs that my carburetors need replacement?

Common symptoms include hard starting, rough idle, poor acceleration, excessive fuel consumption, black smoke from exhaust, and uneven engine performance. Visible damage, fuel leaks, or severe corrosion also indicate replacement is needed.

How often should carburetors be cleaned or replaced?

Clean carburetors annually or more frequently if you use ethanol-blended fuel or store your boat for extended periods. Replace carburetors when cleaning no longer resolves performance issues or if internal components are worn or damaged.

Will these carburetors work with ethanol fuel?

These carburetors are compatible with modern marine fuels, including those containing ethanol. However, ethanol can accelerate wear and deposit buildup, so regular maintenance and fuel stabilizer use are recommended.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

• Verify images/specifications against your original part. If anything differs—even if your model appears compatible—do not purchase.
• This is an aftermarket replacement, not an OEM component.
• Professional installation is recommended for safety and performance.

About Sea Sierra

• Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
• Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
• Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.