Water Pump Impeller – Fits Johnson/Evinrude OMC 40 HP (Replaces 390286, 0390286, 777835, 0777835)

$9.99 $15.00

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Water Pump Impeller – Fits Johnson/Evinrude OMC 40 HP (Replaces 390286, 0390286, 777835, 0777835) 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 for Johnson/Evinrude OMC 40 HP 2-stroke outboard engines. It is designed to fit models manufactured between 1974–1976, 1981–1987, and specifically a range of models from 1983–1986, ensuring reliable cooling performance.

This part serves as a direct interchange for OEM numbers 390286, 0390286, 777835, and 0777835, and aftermarket references including Sierra 18-3366, CEF 500353, Mallory 9-45212, and GLM 89990.

Engineered for direct installation without modification.
Constructed from durable neoprene rubber for a long service life.
Includes one water pump impeller as shown in the package contents.

Part Number Matrix

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

Brand	Part Number
OMC/Johnson/Evinrude	390286
OMC/Johnson/Evinrude	0390286
OMC/Johnson/Evinrude	777835
OMC/Johnson/Evinrude	0777835
Sierra	18-3366
CEF	500353
Mallory	9-45212
RCS	18-3366/183366
GLM	89990
SEI Marine	96-399-05E
Soxa Marine	17IO016/17IO016K

Engine & Model Compatibility

Confirm your engine model/year in the table below.

Evinrude Outboard Models

Brand	Model	Rated HP	Stroke	Years	OEM Part No.
Evinrude	Outboard	40	2-Stroke	1974–1976	390286
Evinrude	Outboard	40	2-Stroke	1981–1987	390286
Evinrude	E40RSLR	40	2-Stroke	1983–1986	390286
Evinrude	E40RSR	40	2-Stroke	1983–1986	390286
Evinrude	E40RWCDB	40	2-Stroke	1983–1986	390286
Evinrude	E40RWCOM	40	2-Stroke	1983–1986	390286
Evinrude	E40RWCRA	40	2-Stroke	1983–1986	390286
Evinrude	E40RWLCDB	40	2-Stroke	1983–1986	390286
Evinrude	E40RWLCOM	40	2-Stroke	1983–1986	390286
Evinrude	E40RWLCRA	40	2-Stroke	1983–1986	390286
Evinrude	E40RWLCTR	40	2-Stroke	1983–1986	390286
Evinrude	E40RWLTR	40	2-Stroke	1983–1986	390286

Johnson Outboard Models

Brand	Model	Rated HP	Stroke	Years	OEM Part No.
Johnson	Outboard	40	2-Stroke	1974–1976	390286
Johnson	Outboard	40	2-Stroke	1981–1987	390286
Johnson	J40RSLR	40	2-Stroke	1983–1986	390286
Johnson	J40RSR	40	2-Stroke	1983–1986	390286
Johnson	J40RWCDB	40	2-Stroke	1983–1986	390286
Johnson	J40RWCOM	40	2-Stroke	1983–1986	390286
Johnson	J40RWCRA	40	2-Stroke	1983–1986	390286
Johnson	J40RWCTR	40	2-Stroke	1983–1986	390286
Johnson	J40RWLCDB	40	2-Stroke	1983–1986	390286
Johnson	J40RWLCOM	40	2-Stroke	1983–1986	390286
Johnson	J40RWLCRA	40	2-Stroke	1983–1986	390286
Johnson	J40RWLCTR	40	2-Stroke	1983–1986	390286

Technical Specs

Product Type: Water Pump Impeller
Installation: Direct replacement
Material: Neoprene Rubber
Number of Blades: 6
Hub/Shaft Size: 17.5 mm (0.689 in)
Impeller Diameter: 50.9 mm (2.004 in)
Impeller Height: 19 mm (0.748 in)
Product Box Dimensions: 11.0 in (L) x 7.5 in (W) x 2.5 in (H)
Compatibility: Johnson/Evinrude/OMC Outboards
Warranty: 1-year against manufacturing defects under normal use

What’s in the Box

1 x Water Pump Impeller (Replaces 390286)

Installation Notes

Before starting, disconnect the engine's battery and ensure the engine is cool.
Remove the lower unit (gearcase) from the outboard motor by unbolting it according to your service manual.
Locate the water pump housing on top of the lower unit and remove its mounting bolts.
Carefully lift the housing off and slide the old impeller off the driveshaft. Note the rotational direction of the old blades.
Clean any debris or corrosion from the inside of the pump housing and the base plate. Inspect for scoring or damage.
Lightly lubricate the new impeller and the interior of the housing with a marine-safe lubricant or soapy water.
Install the new impeller onto the driveshaft, turning the shaft clockwise to gently bend the blades into the correct orientation as you slide the housing down.
Reassemble the water pump housing, ensuring any gaskets or o-rings are correctly seated. Torque the bolts to manufacturer specifications.
Reinstall the lower unit onto the outboard leg and securely tighten all bolts.
Reconnect the battery. Before launching, use a flush attachment to supply water to the engine and test run it to confirm a steady water stream from the "tell-tale" outlet.

Troubleshooting & FAQ

How do I know if this impeller fits my 40 HP Johnson/Evinrude?

This impeller is designed for specific 40 HP 2-stroke models. Please verify your engine's model and year against the compatibility charts provided. It fits general models from 1974–1976 and 1981–1987, with more detailed model fits for 1983–1986. If your engine is outside these ranges, this part may not be compatible.

What are the signs of a failing water pump impeller?

Common signs include a weak or non-existent water stream from the tell-tale (pee) outlet, engine overheating alarms, or a steam/hot water discharge. Upon inspection, a bad impeller will often have cracked, brittle, or missing rubber blades.

How often should I replace my impeller?

For preventative maintenance, it is recommended to inspect your impeller annually and replace it every 1-2 years or after every 100-200 hours of engine use, regardless of its appearance. This helps prevent unexpected failures and potential engine damage from overheating.

Is lubrication necessary during installation?

Yes, lightly lubricating the inside of the pump housing and the new impeller with a marine-grade grease or soapy water is highly recommended. This helps ease installation, prevents blade damage during initial dry startup, and can extend the part's service life.

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.

About Sea Sierra

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