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Carburetor Assembly – Fits Tohatsu & Nissan 9.9-18HP (Replaces 3G2-03100-0, 3G2-03100-2)

Sale price $75.00 Regular price $120.00
Shipping calculated at checkout.

Carburetor Assembly – Fits Tohatsu & Nissan 9.9-18HP (Replaces 3G2-03100-0, 3G2-03100-2) is backordered and will ship as soon as it is back in stock.


Worry-free returns

You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).

You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).

If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.

Delivery and Shipping

Free standard shipping on all orders under 1 KG

If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This Carburetor Assembly – Fits Tohatsu & Nissan 9.9HP/15HP/18HP Two-Stroke Outboards is designed for reliable performance in 2-stroke outboard engines, primarily covering Tohatsu M9.9D2, M15D2, and M18E2 models, along with their Nissan-branded equivalents.

It serves as a direct interchange for Tohatsu part numbers 3G2-03100-0 through 3G2-03100-5 and Nissan numbers 3G2-03100-0M through 3G2-03100-4M.

  • Installation Method: Direct Replacement
  • Housing Material: High-Grade Aluminum Alloy
  • Includes factory-set jetting for specified engine applications

Part Number Matrix

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

Brand Part Number Notes
Tohatsu 3G2-03100-0
Tohatsu 3G2-03100-1
Tohatsu 3G2-03100-2
Tohatsu 3G2-03100-3
Tohatsu 3G2-03100-4
Tohatsu 3G2-03100-5
Nissan 3G2-03200-0M Nissan-branded equivalent
Nissan 3G2-03100-0M Nissan-branded equivalent
Nissan 3G2-03100-1M Nissan-branded equivalent
Nissan 3G2-03100-2M Nissan-branded equivalent
Nissan 3G2-03100-3M Nissan-branded equivalent
Nissan 3G2-03100-4M Nissan-branded equivalent

Engine & Model Compatibility

Confirm your engine model/year in the table below.

Tohatsu & Nissan: This carburetor fits specific D2 and E2 series two-stroke models. Verify your model number matches.

Brand Model Rated HP Stroke OEM Part No. Notes
Tohatsu M9.9D2 9.9 2-Stroke 3G2-03100-0/1/2/3/4/5
Tohatsu M15D2 15 2-Stroke 3G2-03100-0/1/2/3/4/5
Tohatsu M18E2 18 2-Stroke 3G2-03100-0/1/2/3/4/5
Nissan NS9.9D2 9.9 2-Stroke 3G2-03100-0M/1M/2M/3M/4M Nissan-branded version
Nissan NS15D2 15 2-Stroke 3G2-03100-0M/1M/2M/3M/4M Nissan-branded version
Nissan NS18E2 18 2-Stroke 3G2-03100-0M/1M/2M/3M/4M Nissan-branded version

Mercury Cross-Reference: This part is known to cross-reference with certain Mercury outboards that share a Tohatsu platform. Verify serial number ranges carefully.

Brand Model Rated HP Stroke Notes
Mercury 9.9HP 9.9 2-Stroke Mercury serial range: 0N059858 and up
Mercury 15HP 15 2-Stroke Mercury serial ranges: 0N001590 through 0N055284 and 0N055285 and up
Mercury 18HP 18 2-Stroke Mercury serial ranges: 0N001590 through 0N055284 and 0N055285 and up

Technical Specs

Product Type
Carburetor Assembly
Installation
Direct Replacement
Fuel Type
Gasoline
Housing Material
Aluminum Alloy
Weight
0.53 kg (1.17 lb)
Other Technical Attributes
Includes factory-set jetting for specified engine applications
Warranty
1 Year

What’s in the Box

  • 1 x Carburetor Assembly (Replaces 3G2-03100-0/1/2/3/4/5)

Installation Notes

  1. Ensure the engine is off, cool, and disconnected from the fuel supply.
  2. Carefully disconnect the fuel lines, throttle linkage, and any choke or electrical connections from the old carburetor.
  3. Remove the mounting nuts or bolts securing the old carburetor and remove it. Be careful not to drop anything into the intake manifold.
  4. Clean the mounting surface and install a new gasket if required.
  5. Mount the new carburetor assembly, ensuring it is properly aligned. Tighten the mounting hardware to the manufacturer-specified torque.
  6. Reconnect the fuel lines, throttle linkage, and other connections.
  7. Prime the fuel system and check for leaks before starting the engine.
  8. Start the engine and allow it to warm up. Adjust the idle speed screw if necessary, but do not alter factory-set jetting unless you are an experienced technician.

Troubleshooting & FAQ

How do I know if this carburetor will fit my engine?

The surest way is to match your existing part number to one of the numbers listed in the "Part Number Matrix." You can also check your engine's model and serial number against the "Engine & Model Compatibility" table. When in doubt, compare our product photos with your original part.

Are any adjustments needed before installation?

This carburetor comes with factory-set jetting appropriate for the specified Tohatsu and Nissan models. In most cases, only a minor idle speed adjustment is needed after installation. Avoid changing the internal jets unless you are confident in carburetor tuning.

What are the signs of a failing carburetor?

Common symptoms include hard starting, rough idling, stalling, poor acceleration, fuel leaks, or a noticeable decrease in fuel efficiency. If you experience these issues, the carburetor may be clogged or worn and require replacement.

Can I clean my old carburetor instead of replacing it?

Cleaning can sometimes resolve issues caused by fuel deposits. However, if internal components are worn, gaskets are degraded, or the housing is corroded, replacement is the more reliable long-term solution.

Is a new gasket included?

This listing is for the carburetor assembly itself. Mounting gaskets are typically sold separately. We recommend using a new gasket during installation to ensure a proper seal.

How often should a carburetor be replaced?

There is no fixed replacement interval. Replacement is based on condition and performance. Regular use of fuel stabilizer can extend its life, while long periods of storage with old fuel can cause premature failure.

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 vs 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.

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