Water Pump Impeller Kit – Fits Johnson/Evinrude 20–35 HP (Replaces 393630, 0393630)
This water pump impeller kit is a direct replacement for Johnson/Evinrude 20–35 HP, 2-stroke outboard motors from 1980–2005. It provides all necessary components for a complete rebuild of the water pump assembly, ensuring your engine maintains proper cooling and performance.
This kit is a direct replacement for Johnson/Evinrude OEM part numbers 393630 and 0393630, as well as several aftermarket equivalents.
- Engineered as a direct OEM replacement for straightforward installation.
- Includes a durable 6-blade neoprene impeller and a metal/aluminum housing for reliable, long-lasting performance.
- Comes as a complete kit with all required gaskets, O-rings, and hardware.
Part Number Cross-Reference
Use this table to confirm equivalent part numbers across OEM and aftermarket brands.
Brand |
Part Number |
Johnson/Evinrude |
393630 / 0393630 |
Sierra |
18-3382 |
GLM |
12960 |
Mallory |
9-48211 |
CEF |
500350 |
Compatible Engine Models
Confirm your engine model/year in the table below. For Johnson/Evinrude owners, here’s a guide to help you identify your engine’s serial/model: Johnson/Evinrude Serial Number Guide.
Brand |
Model |
Rated HP |
Stroke |
Years |
OEM Part No. |
Notes |
Johnson/Evinrude |
Various |
20 |
2-Stroke |
1985 & Up |
393630 |
|
Johnson/Evinrude |
Various |
25 |
2-Stroke |
1985 & Up |
393630 |
|
Johnson/Evinrude |
Commercial |
25 |
2-Stroke |
1998–2001 |
393630 |
|
Johnson/Evinrude |
Various |
30 |
2-Stroke |
1980–1982 |
393630 |
|
Johnson/Evinrude |
Various |
30 |
2-Stroke |
1983 & Up |
393630 |
2-cylinder models |
Johnson/Evinrude |
Various |
35 |
2-Stroke |
1980–1982 |
393630 |
|
Johnson/Evinrude |
Various |
35 |
2-Stroke |
1983 & Up |
393630 |
2-cylinder models |
Technical Specifications
Specification |
Value |
Product Type |
Water Pump Impeller Kit with Housing |
Installation |
Direct OEM replacement |
Housing Material |
Metal/Aluminum with Nylon PA66 Plastic |
Impeller Material |
Neoprene rubber |
Impeller Design |
6-blade |
Housing Color |
White/Silver |
Weight |
283 g (0.62 lb) |
Warranty |
90 days (varies by seller) |
Other Technical Attributes |
Complete kit with all necessary gaskets, O-rings, and hardware for installation |
Package Contents
- 1 x Neoprene Impeller (395289)
- 1 x Impeller Key (330619)
- 1 x Gasket (325537)
- 1 x Wear Plate (328755)
- 1 x Pump Cup (328751)
- 1 x Pump Housing (393632)
- 1 x Grommet (302497)
- 1 x Brass Bushing (328754)
- 4 x O-ring (311338 x 2 / For Bushing 301877 / 554545)
- 1 x Seal (328753)
- 6 x Bolt with Washer (324960 / 318452)
Installation Guide
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Safety First: Disconnect the battery and ensure the engine is securely mounted.
-
Drain Gear Lube: Place a drain pan under the lower unit and remove the drain/fill plugs to drain the gear lube.
-
Remove Lower Unit: Unbolt the lower unit (gearcase) from the outboard's leg. You may need to disconnect the shift linkage.
-
Disassemble Pump: Carefully remove the bolts holding the water pump housing in place and lift it off the driveshaft.
-
Inspect Old Parts: Note the rotational direction of the old impeller's blades. Remove the old impeller, wear plate, key, and gaskets.
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Clean Surfaces: Thoroughly clean the mounting surfaces on the gearcase and the driveshaft, removing any old gasket material or debris.
-
Install New Components: Lightly grease the new seals and O-rings. Install the new wear plate and gaskets.
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Install Impeller: Slide the impeller key onto the driveshaft and then slide the new impeller on, twisting it in the correct rotational direction to seat the blades.
-
Reassemble Pump: Place the new pump cup and housing over the impeller and fasten securely with the new bolts, tightening to manufacturer torque specs.
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Reinstall Lower Unit: Guide the lower unit back into place, ensuring the driveshaft and water tube align correctly. Reconnect the shift linkage.
-
Refill Gear Lube: Fill the lower unit with fresh marine gear lubricant according to your owner's manual.
-
Test Operation: Reconnect the battery. Safely test the engine in water, verifying a strong, steady stream of water from the tell-tale outlet.
Troubleshooting & FAQ
Q: How do I confirm this fits my engine?
A: Check the "Compatible Engine Models" table and cross-reference your motor's model, HP, and year. Ensure the OEM part number 393630 matches your service manual's requirement. Verifying against the product images is also recommended.
Q: What are the signs of a failing water pump impeller?
A: Common signs include a weak or intermittent water stream from the "tell-tale" outlet, engine overheating alarms, and a visibly cracked, brittle, or worn impeller during inspection.
Q: How often should the impeller be replaced?
A: For optimal performance and to prevent engine damage, it is recommended to inspect the impeller annually and replace it every 1-2 years, or more frequently if operating in saltwater or sandy/silty conditions.
Q: OEM vs. Aftermarket?
A: This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.
Q: How fast do you ship and how much does it cost?
A: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.
Q: What is your warranty and return policy?
A: This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.
Important Notes
- Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
- This product is an aftermarket replacement part and is not an OEM component.
-
Professional installation is recommended to ensure safety and optimal performance.
Why Choose JLM MARINE?
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Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
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Fast Global Shipping: Free delivery worldwide in 5–15 days.
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Direct from Manufacturer: Competitive pricing without compromising quality.