Water Pump Impeller – Fits Tohatsu/Mercury/Evinrude 2-6 HP (Replaces 369-65021-1, 3C8-65021-2)

$21.50 $34.00

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Water Pump Impeller – Fits Tohatsu/Mercury/Evinrude 2-6 HP (Replaces 369-65021-1, 3C8-65021-2) is backordered and will ship as soon as it is back in stock.

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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).

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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 aftermarket Water Pump Impeller – Fits Tohatsu/Mercury/Evinrude 2.5–6 HP is engineered to restore cooling performance in a wide range of small outboard motors. It is a direct-fit replacement for Tohatsu 2–6 HP 2-Stroke & 2.5–6 HP 4-Stroke (1997–2014), Mercury 2.5–6 HP 4-Stroke & 3.3–5 HP 2-Stroke (1999–2014), and various Evinrude/Nissan 2-Stroke and 4-Stroke models from 1999 to 2014.

It provides a direct interchange for OEM part numbers including Tohatsu 369-65021-1, 3C8-65021-2, Mercury 47-16154-3, Evinrude 5040180, and aftermarket equivalents like Sierra 18-3098.

Installs as a direct replacement with no modifications needed.
Made from durable, chlorine-resistant neoprene for reliable service.
Features a 6-blade design to ensure consistent coolant flow.

Part Number Matrix

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

Brand	Part Number	Superseded By	Notes
Tohatsu	369-65021-1		For 2–6 HP models
Tohatsu	3C8650210M	3C8-65021-2	Physically identical to 369-65021-1
Tohatsu	3C8650211M	3C8-65021-2	Physically identical to 369-65021-1
Tohatsu	3C8-65021-2		For 40-60 HP models, physically identical
Mercury	47-16154-3	8M0204676
Mercury	8M0204676		Current OEM part number
Evinrude	5040180 / 05040180
Sierra	18-3098		Aftermarket Cross-Reference
Sierra	18-8922		Aftermarket Cross-Reference
CEF	500377		Aftermarket Cross-Reference
PAT	T5-03000300		Aftermarket Cross-Reference

Engine & Model Compatibility

Confirm your engine model and year in the tables below. Note that the same impeller fits different HP ranges across brands.

For Tohatsu Owners: This impeller replaces both 369-65021-1 (on 2–6 HP models) and 3C8-65021-2 (on 30–60 HP models). The parts are physically identical.

For Mercury Owners: Fits a range of 2.5 HP to 6 HP four-stroke engines and 3.3 to 5 HP two-stroke engines. Please verify serial number ranges where noted.

For Evinrude/Nissan Owners: Widely used across 2 HP to 6 HP models in both 2-stroke and 4-stroke configurations.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
Tohatsu	M40D, M40D2, M50D, M50D2	40–50	2-Stroke	2006+	3C8-65021-2
Tohatsu	TLDI MD30B2, MD40A/B/B2, MD50A/B2	30–50	2-Stroke TLDI	2006–2018	3C8-65021-2
Tohatsu	M40C	40	2-Stroke	2013	3C8-65021-2	Model 1301
Tohatsu	MFS40A, MFS50A, MFS60	40–60	4-Stroke	2014+	3C8-65021-2
Tohatsu	M2, M2.5, M3.5A, M3.5B	2–3.5	2-Stroke	1999–2019	369-65021-1	Earlier models
Tohatsu	M4, M5, M6	4–6	2-Stroke	1997–2014	369-65021-1	Earlier models
Tohatsu	MFS2.5, MFS3.5	2.5–3.5	4-Stroke	2006+	369-65021-1
Tohatsu	MFS4, MFS5, MFS6	4–6	4-Stroke	1999–2014	369-65021-1
Mercury		2-2.5-3.5	4-Stroke (Carb)	2006+	47-16154-3/8M0204676	Serial from 0R131842+
Mercury		4–5–6	4-Stroke	1999+	47-16154-3/8M0204676	Serial from 0P073456+
Mercury		3.3–5	2-Stroke	1999–2014	47-16154-3
Nissan/Evinrude	NS2, NS2.5, NS3.5	2–3.5	2-Stroke	1999–2019	369-65021-1
Nissan/Evinrude	NS4, NS5, NS6	4–6	2-Stroke	1997–2014	369-65021-1
Nissan/Evinrude	NSF2.5, NSF3.5	2.5–3.5	4-Stroke	2006+	369-65021-1
Nissan/Evinrude	NSF4, NSF5, NSF6	4–6	4-Stroke	1999–2014	369-65021-1
Evinrude		3–5	2-Stroke	1999–2014	5040180/05040180

Technical Specs

Product Type: Water Pump Impeller
Installation: Direct replacement
Material: Neoprene
Dimensions: A: 10.35 mm (shaft insert diameter)
B: 33.60 mm (overall diameter)
C: 14.35 mm (height)
Blades: 6
Warranty: 1 Year (aftermarket); OEM warranty where applicable
Certification: Manufactured in ISO9002 certified facility (aftermarket)

What’s in the Box

1 x Water Pump Impeller (replaces 369-65021-1 or 3C8-65021-2)

Installation Notes

Disconnect the battery and remove the lower unit (gearcase) from the engine.
Unbolt the water pump housing to access the impeller. Note the blade direction of the old impeller before removal.
Remove the old impeller, woodruff key, and any gaskets.
Thoroughly clean all surfaces of the pump housing and wear plate, removing any debris or salt buildup.
Install new gaskets and place the woodruff key on the driveshaft.
Slide the new impeller onto the shaft. While pushing the housing down, turn the driveshaft clockwise to correctly bend the blades into place.
Bolt the housing back on, tightening bolts to the manufacturer's recommended torque.
Reinstall the lower unit, reconnect the battery, and test the engine in water to verify a strong, steady water flow from the tell-tale outlet.

Troubleshooting & FAQ

How do I confirm this impeller fits my outboard?

The most reliable method is to match your existing part number to one listed in our "Part Number Matrix." You can also check your engine's model, horsepower, and year against the "Engine & Model Compatibility" table. Always visually compare the photos to your old part before ordering.

What is the difference between part numbers 369-65021-1 and 3C8-65021-2?

While these two part numbers apply to different Tohatsu engine horsepower ranges, the impellers themselves are physically identical in dimensions and material. This part is a direct replacement for both OEM numbers.

How often should an impeller be replaced?

As a general rule, we recommend inspecting your impeller annually and replacing it every 1–2 years or every 100–200 hours of use, whichever comes first. Replacement may be needed more frequently if you operate in sandy, silty, or saltwater environments.

What are the signs of a failing water pump impeller?

The most common symptom is the engine overheating, especially at idle or low speeds. Other indicators include a weak or non-existent water stream from the "tell-tale" outlet, or discovering the old impeller's blades are cracked, brittle, or broken during an inspection.

Is this an OEM or aftermarket part?

This listing is for an aftermarket replacement part, not an OEM component. It is built to meet or exceed OEM-level specifications using comparable materials and is manufactured in an ISO 9002 certified facility with batch inspections for quality and consistency.

What are the shipping speed and cost?

We ship worldwide quickly, with typical transit times of 5–15 days for most regions. Standard shipping is free, and expedited options may be available at checkout depending on your location.

What is the warranty and return policy?

This part is covered by a 1-year warranty against manufacturing defects under normal use. If you encounter any issues, please contact our support team with your order details. Returns are accepted within our standard window for items that are unused and in original condition. See our policy page or reach out for instructions.

Safety & Important Info

Verify images and 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

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