Water Pump Impeller Kit – Fits Johnson/Evinrude 8-15 HP (Replaces 394711, 18-3327)

$19.99

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Water Pump Impeller Kit – Fits Johnson/Evinrude 8-15 HP (Replaces 394711, 18-3327) is backordered and will ship as soon as it is back in stock.

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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 Water Pump Impeller Kit – Fits Johnson/Evinrude 8-15 HP (Replaces 394711, 18-3327) provides everything needed for a complete water pump service. It is designed for Johnson/Evinrude 8–15 HP 2-Stroke outboard engines from 1974 and newer, and 8–15 HP 4-Stroke models manufactured between 1995 and 2001.

It serves as a direct replacement for Johnson/Evinrude 394711, Sierra 18-3327, GLM 89770, and Mallory 9-45201.

Engineered for direct-fit installation.
Features a durable neoprene impeller for reliable performance.
Includes the complete housing assembly for a full overhaul.

Part Number Matrix

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

Brand	Part Number
Johnson/Evinrude	394711
Sierra	18-3327
GLM	89770
Mallory	9-45201

Engine & Model Compatibility

Confirm your engine model/year in the table below.

This kit fits a wide range of Johnson and Evinrude outboards. Please verify your specific horsepower, stroke, and year range before ordering.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.
Johnson	Various	8	2-Stroke	1974–Up	394711, 18-3327
Johnson	Various	9.5	2-Stroke	1974–Up	394711, 18-3327
Johnson	Various	9.9	2-Stroke	1974–Up	394711, 18-3327
Johnson	Various	10	2-Stroke	1974–Up	394711, 18-3327
Johnson	Various	15	2-Stroke	1974–Up	394711, 18-3327
Johnson	Various	8	4-Stroke	1995–2001	394711, 18-3327
Johnson	Various	9.9	4-Stroke (211cc)	1996–2004	394711, 18-3327
Johnson	Various	9.9	4-Stroke (305cc)	1995–2001	394711, 18-3327
Johnson	Various	15	4-Stroke	1995–2001	394711, 18-3327
Evinrude	Various	8	2-Stroke	1974–Up	394711, 18-3327
Evinrude	Various	9.9	2-Stroke	1974–Up	394711, 18-3327
Evinrude	Various	10	2-Stroke	1974–Up	394711, 18-3327
Evinrude	Various	15	2-Stroke	1974–Up	394711, 18-3327
Evinrude	Various	9.9	4-Stroke (211cc)	1996–2004	394711, 18-3327
Evinrude	Various	9.9	4-Stroke (305cc)	1995–2001	394711, 18-3327
Evinrude	Various	15	4-Stroke	1995–2001	394711, 18-3327

Note: Does NOT fit the short-lived Johnson rebranded Suzukis from 2002–2007 or any Bombardier-branded 4-stroke models (these are rebranded Tohatsu motors).

Technical Specs

Product Type: Water Pump Impeller Kit with Housing
Installation: Direct Replacement
Material: Neoprene (Impeller)
Housing Material: Composite
Impeller Design: 6-Fin
Engine Type: 2-Stroke and 4-Stroke Gasoline Outboard
Maximum Horsepower: 15 HP
Weight: 198.4g (7 oz)

What’s in the Box

1 x Neoprene Impeller (386084, 18-3050)
1 x Impeller Key (300611)
1 x Wear Plate (318995)
1 x Pump Cup (324097)
1 x Pump Housing (435390)
3 x Grommet (338908/302497/327035)
2 x O-ring (202893/319085)
4 x Installation bolts (302325)

Installation Notes

Disconnect the spark plug wires and secure the engine to prevent accidental starting.
Place a drain pan under the lower unit and remove the gearcase drain screw to empty the gear oil.
Unbolt and carefully lower the gearcase from the engine midsection.
Remove the bolts securing the water pump housing to the gearcase.
Slide the old housing, impeller, and wear plate off the driveshaft. Clean all mating surfaces thoroughly.
Install the new components from the kit in reverse order, lightly greasing the impeller and cup.
Reinstall the gearcase, refill with fresh gear oil, and reconnect spark plug wires before testing.

Troubleshooting & FAQ

How do I know if this kit fits my engine?

Verify that your engine is a Johnson or Evinrude model within the 8–15 HP range and matches the specified years (1974+ for 2-Strokes, 1995–2001 for 4-Strokes). Cross-referencing your existing part number with the provided matrix (394711, 18-3327, etc.) is the best way to ensure a perfect match.

What are the signs of a failing water pump impeller?

Common symptoms include the engine overheating at idle or low speeds, a weak or non-existent stream of water from the tell-tale outlet, and steam from the exhaust. A damaged impeller cannot provide adequate cooling, which can lead to severe engine damage.

How often should I replace my water pump impeller?

For preventative maintenance, it is recommended to replace the impeller every 1-2 years or every 100-200 hours of use, whichever comes first. This interval can be shorter if you frequently operate in sandy, silty, or saltwater conditions.

Is the complete housing included in this kit?

Yes, this is a complete water pump repair kit that includes the pump housing, impeller, wear plate, cup, gaskets, and all necessary hardware for a full replacement.

What’s the difference between this kit and an OEM part?

This is an aftermarket part designed to meet or exceed OEM specifications for fit, form, and function. It offers a cost-effective solution without compromising on quality or performance, using comparable materials and manufacturing processes.

Can I install this kit myself?

While installation is possible for those with mechanical experience, professional installation is recommended. The process involves removing the lower unit, which requires proper tools and knowledge to ensure correct reassembly and sealing.

Is this an OEM part?

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.

What are the shipping speed & cost?

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

What is the warranty and return policy?

This product is 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 for unused items 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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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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