Water Pump Impeller – Fits Mercury/Tohatsu/Evinrude 2.5–6 HP 4-Stroke & 2–5 HP 2-Stroke (Replaces 47-161543, 369-65021-1, 5040180)
Water Pump Impeller – Fits Mercury/Tohatsu/Evinrude 2.5–6 HP 4-Stroke & 2–5 HP 2-Stroke (Replaces 47-161543, 369-65021-1, 5040180) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
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
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Water Pump Impeller – Fits Mercury/Tohatsu/Evinrude 2.5–6 HP 4-Stro...
Product Details
This replacement Water Pump Impeller – Fits Mercury/Tohatsu/Evinrude 2.5–6 HP 4-Stroke & 2–5 HP 2-Stroke is a crucial component for maintaining your engine's cooling system. It is designed for a broad range of small outboard motors, including Mercury/Mariner 2–6 HP 4-Stroke (1999+), 2–5 HP 2-Stroke (1987+), Tohatsu/Nissan 2.5–6 HP 4-Stroke & 2.5–5 HP 2-Stroke, and Evinrude/Johnson 3–5 HP 2-Stroke models.
Engineered for a precise fit, this impeller serves as a direct replacement for Mercury 47-161543, Tohatsu 369-65021-1, Evinrude 5040180, and aftermarket parts including Sierra 18-3098 and Mallory 9-45302.
- Engineered for direct-fit installation.
- Constructed from durable neoprene rubber for reliable performance in marine environments.
- Package includes one water pump impeller.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket manufacturers.
| Brand | Part Number |
|---|---|
| Mercury | 47-161543 |
| Mercury | 47-16154-3 |
| Mercury | 8M0204676 |
| Tohatsu | 369-65021-1 |
| Tohatsu | 369650211 |
| Evinrude | 5040180 |
| Evinrude | 05040180 |
| Sierra | 18-3098 |
| Mallory | 9-45302 |
| Mallory | 9-45302-10 |
| CEF | 500377 |
| PAT | PAT5-03000300 |
Engine & Model Compatibility
Confirm your engine model and year in the table below. Compatibility is determined by the OEM part number and serial number range where applicable.
For Mercury/Mariner models, verify your engine's serial number falls within the specified range (e.g., "0R131842+").
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury | 2.5 HP | 2.5 | 4-Stroke | 1999+ | 47-161543 | SN 0R131842+ |
| Mercury | 3.5 HP (Carb) | 3.5 | 4-Stroke | 1999+ | 47-161543 | SN 0R131842+ |
| Mercury | 4 HP | 4 | 4-Stroke | 1999+ | 47-161543 | SN 0P073456+ |
| Mercury | 5 HP | 5 | 4-Stroke | 1999+ | 47-161543 | SN 0P073456+ |
| Mercury | 6 HP | 6 | 4-Stroke | 1999+ | 47-161543 | SN 0P073456+ |
| Mercury | 2 HP | 2 | 2-Stroke | 1993+ | 47-161543 | SN 0T884302+ |
| Mercury | 3.3 HP w/shift | 3.3 | 2-Stroke | 1993+ | 47-161543 | SN 0D901217+ |
| Mercury | 4 HP (1 CYL) | 4 | 2-Stroke | 1987+ | 47-161543 | SN 0A809601+ |
| Mercury | 5 HP (1 CYL) | 5 | 2-Stroke | 1987+ | 47-161543 | SN 0A809601+ |
Technical Specs
- Product Type
- Water Pump Impeller
- Installation
- Direct Replacement
- Fuel Type
- Gasoline
- Dimensions
- Impeller Height: 14.35 mm (0.56 in), Overall Diameter: 33.6 mm (1.32 in), Hub Shaft Diameter: 10.4 mm (0.41 in)
- Weight
- 10 g (0.35 oz)
- Material
- Neoprene rubber with nylon insert
- Blade Configuration
- 6 blades
- Warranty
- Varies by manufacturer
What’s in the Box
- 1 x Water Pump Impeller (Replaces 47-161543, 369-65021-1, 5040180)
Installation Notes
- Disconnect the negative battery terminal before beginning work.
- Unbolt and carefully remove the lower unit (gearcase) from the outboard's midsection.
- Undo the bolts on the water pump housing and slide it up and off the driveshaft.
- Remove the old impeller, taking note of the original orientation of the blades.
- Clean any debris, salt, or corrosion from the pump housing, wear plate, and driveshaft splines.
- Apply a light film of marine-grade grease or soap-and-water solution to the inside of the housing and to the new impeller.
- Slide the new impeller onto the driveshaft, turning the shaft clockwise to help seat the blades correctly inside the housing.
- Reinstall the water pump housing and tighten the bolts to the torque specified in your service manual.
- Realign and attach the lower unit, ensuring the driveshaft, shift shaft, and water tube are properly connected.
- Reconnect the battery and test the engine in water to verify that water is being discharged from the tell-tale port.
Troubleshooting & FAQ
How do I know if this impeller fits my specific engine?
The best way to confirm fitment is to check your original part number against our Part Number Matrix. If you have a Mercury/Mariner engine, also verify that your motor's serial number falls within the range listed in the compatibility table.
What are the signs of a failing water pump impeller?
Common symptoms include a weak or nonexistent water stream from the "tell-tale" outlet, engine overheating alarms, and reduced engine performance. Visible signs on the old impeller include cracked, brittle, or broken blades.
How often should I replace the impeller?
For preventative maintenance, most manufacturers recommend replacing the water pump impeller every 1-2 years or every 100-200 hours of operation, whichever comes first. This interval can be shorter if you frequently operate in sandy, silty, or saltwater environments.
Is this an OEM or aftermarket part?
This is a high-quality aftermarket replacement part, not an OEM component. It has been manufactured in an ISO 9002 certified facility and is engineered to meet or exceed original equipment specifications using comparable materials.
What are the shipping options and costs?
We offer fast worldwide shipping, with typical transit times of 5–15 days for most regions. Standard shipping is free. If expedited options are available for your location, they will be presented at checkout.
What is the warranty and return policy?
This product is covered by a 1-year warranty against manufacturing defects under normal marine use. Should an issue arise, please contact our support team with your order information. Returns are accepted within our standard return window for items that are unused and in their original condition.
Safety & Important Info
- Verify the images and specifications provided against your original part before purchasing. If any detail differs—even if your model is listed as compatible—do not complete the purchase.
- This is an aftermarket replacement component, not an Original Equipment Manufacturer (OEM) part.
- For safety and optimal performance, professional installation by a qualified marine mechanic is highly recommended.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and rigorously tested for performance in real-world saltwater and freshwater conditions.
- Fast Global Fulfillment — We offer free standard delivery to most regions worldwide, typically arriving within 5–15 business days.
- Manufacturer-Direct Value — By working directly with our manufacturing partners, we provide fair, competitive pricing without compromising on material quality or quality control.
Payment & Security
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