Water Pump Impeller for Johnson/Evinrude 8, 9.9 & 15 HP Outboards — Replaces OEM 386084
Water Pump Impeller for Johnson/Evinrude 8, 9.9 & 15 HP Outboards — Replaces OEM 386084 is backordered and will ship as soon as it is back in stock.
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Water Pump Impeller for Johnson/Evinrude 8, 9.9 & 15 HP Outboar...
Water Pump Impeller for Johnson/Evinrude 8, 9.9 & 15 HP Outboards — Replaces OEM 386084 is backordered and will ship as soon as it is back in stock.
Product Details
This water pump impeller is a replacement for the Johnson/Evinrude water pump impeller identified by OEM part number 386084. Catalog application data lists this impeller for Johnson and Evinrude outboard engines rated at 8, 9.9, and 15 HP, 1974 and newer. It helps circulate cooling water through the outboard to support proper operating temperature and reduce the risk of overheating.
The impeller is supplied as the core replacement impeller. Confirm the OEM number, impeller dimensions, engine model, and serial-number range before ordering. Application information can vary between engine configurations, and the horsepower range alone should not be treated as a complete fitment confirmation.
- Replacement water pump impeller for selected Johnson/Evinrude outboards.
- Reference application: 8, 9.9, and 15 HP engines from 1974 and newer.
- Designed around the OEM 386084 dimensions listed below.
- Impeller only; do not assume that a drive key, O-rings, gaskets, or other water-pump components are included.
Part Number Cross-Reference
These references identify the impeller application or an aftermarket catalog equivalent. Always compare the original part before installation.
| Brand or Reference | Part Number | Reference Type |
|---|---|---|
| Johnson/Evinrude | 386084 | OEM reference |
| Sierra | 18-3050 | Aftermarket replacement reference for OEM 386084 |
| GLM | 89770 | Aftermarket catalog reference for OEM 386084 |
Engine Compatibility
The catalog application below is a general reference. Verify the exact model and serial-number range against your engine and the original impeller before purchase.
| Brand | Engine Rating | Stroke | Application Years | OEM Reference | Notes |
|---|---|---|---|---|---|
| Johnson | 8, 9.9 & 15 HP | Not specified in the cited catalog application | 1974 and newer | 386084 | Confirm exact model and serial number. |
| Evinrude | 8, 9.9 & 15 HP | Not specified in the cited catalog application | 1974 and newer | 386084 | Confirm exact model and serial number. |
Technical Specifications
- Product Type
- Water pump impeller
- OEM Reference
- 386084
- Outside Diameter
- Approximately 1.50 in (38.1 mm)
- Inside Diameter
- Approximately 0.500 in (12.7 mm)
- Installation
- Replacement impeller installed in the water-pump housing on the engine driveshaft
- Drive Key
- Not specified as included; inspect and replace the key separately as required
- Stroke, Blade Count, Material and Weight
- Not specified in the cited application and identification data
What's in the Box
- 1 x Water pump impeller
Important: A drive key, O-rings, gaskets, wear plate, water-pump cup, and housing are not listed as included with this impeller. Inspect the complete water-pump assembly and obtain any required service parts separately.
Installation Notes
- Disconnect the battery, remove the safety lanyard, and follow the manufacturer's service procedure for your engine.
- Remove the lower unit and water-pump housing according to the service manual.
- Remove the old impeller and inspect the housing, wear plate, drive key, and related seals for damage or wear.
- Clean debris from the water-pump housing and confirm that the replacement impeller matches the original diameter, bore, and keyway arrangement.
- Install the drive key if required, then fit the impeller onto the driveshaft with the keyway correctly aligned.
- Install the water-pump housing while turning the driveshaft in the manufacturer's specified direction so the vanes are correctly oriented.
- Reassemble the lower unit using the correct gaskets, O-rings, fasteners, and torque specifications.
- Run the engine only with an adequate cooling-water supply and verify a steady tell-tale stream before normal operation.
Troubleshooting & FAQ
How do I know if the impeller needs replacing?
Common symptoms include a weak or missing tell-tale stream, overheating, a temperature alarm, or steam from the exhaust. Remove and inspect the impeller for cracked, torn, hardened, permanently deformed, or missing vanes. If an impeller has failed, inspect the cooling passages and water-pump housing for debris or damage.
What engines does this impeller fit?
The cited catalog application identifies OEM 386084 for Johnson and Evinrude outboards rated at 8, 9.9, and 15 HP from 1974 and newer. Because model and serial-number conditions may differ, verify the engine's exact OEM part number and compare the original impeller dimensions before ordering.
Does the impeller include the drive key or O-rings?
This listing is for the impeller only. A drive key, O-rings, gaskets, and other water-pump components are not specified as included. Check the existing parts and obtain the correct service components separately when necessary.
Why is the drive key important?
The drive key transfers rotation from the driveshaft to the impeller. A damaged, missing, or incorrect key can prevent the impeller from turning and may cause immediate loss of cooling-water circulation.
How often should a water-pump impeller be replaced?
Replacement intervals depend on the engine manufacturer's maintenance schedule and operating conditions. Inspect the impeller during scheduled service and replace it sooner after extended storage, operation in sandy or silty water, or any overheating event.
What should I verify before ordering?
Verify the engine brand, exact model, serial-number range, horsepower, OEM part number, outside diameter, inside diameter, and keyway arrangement. Do not rely on horsepower alone when multiple water-pump configurations are available.
Safety & Important Information
- Use the manufacturer's service manual for lower-unit removal, installation direction, fastener torque, and testing procedures.
- Never run an outboard without an adequate cooling-water supply.
- Stop operation immediately if the tell-tale stream is weak or absent, the engine overheats, or a temperature alarm activates.
- This is an aftermarket replacement reference listing, not a claim that the product is manufactured by Johnson, Evinrude, OMC, Sierra, or GLM.
About Sea Sierra
- Marine Replacement Parts — We provide replacement components for routine outboard maintenance and repair.
- Fitment-Focused Listings — Compare OEM references, dimensions, engine details, and original parts before ordering.
- Customer Support — Contact us with the engine model, serial number, and original part details when you need help checking an application.
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