Water Pump Impeller – Fits Johnson/Evinrude 40-75 HP (Replaces 396809, 777214, 878883)

$13.99

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Water Pump Impeller – Fits Johnson/Evinrude 40-75 HP (Replaces 396809, 777214, 878883) is backordered and will ship as soon as it is back in stock.

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Product Details

This is a direct replacement Water Pump Impeller – Fits Johnson/Evinrude 40-75 HP (1979-1989) (Replaces 396809, 777214) for 2-stroke outboard motors in the specified horsepower range and model years. It is engineered to restore cooling system performance by ensuring proper water circulation, preventing engine overheating.

It provides a direct interchange for Johnson/Evinrude part numbers 396809, 0396809, 777214, 0777214, and 0777828. It also cross-references with Mercury 878883, Sierra 18-3368, and CEF 500346C.

Installs directly into the small housing water pump assembly.
Designed for key drive connections on the driveshaft.
Includes the required plastic drive key for a complete installation.

Part Number Matrix

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

Brand	Part Number	Notes
Johnson/Evinrude	396809 / 0396809	OEM Reference
Johnson/Evinrude	777214 / 0777214	OEM Reference
Johnson/Evinrude	0777828	OEM Reference
Mercury	878883	Cross-reference only
Sierra	18-3368	Aftermarket Interchange
CEF	500346C	Aftermarket Interchange

Engine & Model Compatibility

Confirm your engine model/year in the table below.

This impeller fits various Johnson/Evinrude 2-stroke models from 40 to 75 HP manufactured between 1979 and 1994 that use the small water pump housing.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
Johnson/Evinrude	Various	40	2-Stroke	1984–1988	396809, 777214	Small housing
Johnson/Evinrude	Commercial	40	2-Stroke	1993–1994	396809, 777214	Small housing
Johnson/Evinrude	Commercial	45	2-Stroke	1986–1994	396809, 777214	Small housing
Johnson/Evinrude	Various	48	2-Stroke	1987–1988	396809, 777214	Small housing
Johnson/Evinrude	Various	50	2-Stroke	1986–1988	396809, 777214	Small housing
Johnson/Evinrude	Commercial	55	2-Stroke	1986–1994	396809, 777214	Small housing
Johnson/Evinrude	Various	40-75	2-Stroke	1979–1989	396809, 777214	Small housing

Technical Specs

Product Type: Water Pump Impeller
Installation: Direct replacement in small housing water pump assembly
Dimensions: A: 16.04 mm, B: 70 mm, C: 22.3 mm
Housing Material: Rubber
Connection: Small housing - key drive
Other Technical Attributes: Includes drive key

What’s in the Box

1 x Water Pump Impeller (396809, 777214)
1 x Plastic Key (Included)

Installation Notes

Disconnect the battery and remove the propeller for safety.
Place a drain pan under the lower unit and remove the gear oil drain/fill screws to drain the oil.
Unbolt the lower unit (gearcase) from the midsection of the outboard.
If applicable, disconnect the shift linkage rod.
Carefully lower and remove the gearcase from the engine.
Unscrew the bolts holding the water pump housing cover.
Slide the old impeller off the driveshaft, taking note of its rotational orientation and removing the old key.
Thoroughly clean the impeller housing, wear plate, and all sealing surfaces.
Install the new drive key into the driveshaft keyway.
Lubricate the inside of the housing and slide the new impeller onto the shaft, turning the shaft in its normal rotational direction.
Reinstall the water pump housing and torque its bolts to the manufacturer's specification.
Reattach the gearcase, reconnect the shift linkage, refill with fresh gear oil, and test engine cooling at idle.

Troubleshooting & FAQ

How do I confirm this impeller fits my specific engine model?

First, check the Engine & Model Compatibility table to see if your engine's horsepower, model type, and year range are listed. This part is specifically for models with the "small housing" water pump. The most reliable method is to cross-reference the part number from your existing impeller or service manual with the numbers in our Part Number Matrix, such as 396809 or 777214.

What are the common signs of a failing water pump impeller?

The earliest sign is often a weak or intermittent water stream from the "tell-tale" outlet. Other symptoms include engine overheating alarms, steam from the exhaust, or a complete lack of water output, which indicates a critical failure.

How often should I replace my outboard's impeller?

For preventative maintenance, it is recommended to replace the impeller every 1 to 2 years, or every 100-200 hours of operation, depending on usage conditions (e.g., saltwater vs. freshwater). An impeller can stiffen and degrade over time even with low hours.

Is the included plastic drive key important for installation?

Yes, the drive key is absolutely critical. It locks the impeller to the driveshaft, forcing it to spin and pump water. Installing the impeller without the key will result in it free-spinning on the shaft, providing no cooling and leading to rapid engine overheating.

Can I perform this installation myself?

While DIY installation is possible with proper mechanical knowledge and tools, it is a moderately complex job. Mistakes during reassembly (e.g., misaligning the shift shaft or water tube) can cause significant damage. We recommend professional installation or following a detailed service manual for your specific engine.

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.

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