Water Pump Impeller Repair Kit – Fits Mercury 175–300 HP & 450R V6/V8 4-Stroke Outboards (Replaces 47-8M0142980/8M0205803)
Water Pump Impeller Repair Kit – Fits Mercury 175–300 HP & 450R V6/V8 4-Stroke Outboards (Replaces 47-8M0142980/8M0205803) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
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Water Pump Impeller Repair Kit – Fits Mercury 175–300 HP & 450R...
Water Pump Impeller Repair Kit – Fits Mercury 175–300 HP & 450R V6/V8 4-Stroke Outboards (Replaces 47-8M0142980/8M0205803) is backordered and will ship as soon as it is back in stock.
Product Details
This Water Pump Impeller Repair Kit is designed for Mercury Marine 4-stroke outboards, including 175–300 HP V6 (3.4L) and V8 (4.6L) models, plus 450R racing engines (2019 and newer, S/N 2B529482+). It provides everything needed for a complete water pump service to maintain engine cooling and prevent overheating.
This kit is a direct interchange for Mercury part numbers 47-8M0142980, 8M0205803, and 98-8M0142980.
- Engineered as a direct-fit replacement for straightforward installation.
- Features a high-performance neoprene rubber impeller for flexibility and durability.
- Includes all necessary gaskets, seals, and hardware for a full repair.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury | 47-8M0142980 |
| Mercury | 8M0205803 |
| Mercury | 98-8M0142980 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Mercury Marine outboards, this kit fits select V6 (3.4L) and V8 (4.6L) models from 2019 and newer with serial numbers 2B529482 and above.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury | V6 Outboards | 175 | 4-Stroke | 2019 and newer (S/N 2B529482+) | 47-8M0142980/8M0205803 | 3.4L displacement |
| Mercury | V6 Outboards | 200 | 4-Stroke | 2019 and newer (S/N 2B529482+) | 47-8M0142980/8M0205803 | 3.4L displacement |
| Mercury | V6 Outboards | 225 | 4-Stroke | 2019 and newer (S/N 2B529482+) | 47-8M0142980/8M0205803 | 3.4L displacement |
| Mercury | V6 Outboards | 250 | 4-Stroke | 2019 and newer (S/N 2B529482+) | 47-8M0142980/8M0205803 | 3.4L displacement |
| Mercury | V8 Outboards | 250 | 4-Stroke | 2019 and newer (S/N 2B529482+) | 47-8M0142980/8M0205803 | 4.6L displacement |
| Mercury | V8 Outboards | 300 | 4-Stroke | 2019 and newer (S/N 2B529482+) | 47-8M0142980/8M0205803 | 4.6L displacement |
| Mercury | Racing 450R | 450 | 4-Stroke | 2019 and newer (S/N 2B529482+) | 47-8M0142980/8M0205803 | 4.6L displacement |
Technical Specs
- Product Type
- Water Pump Impeller Repair Kit
- Installation
- Direct replacement
- Housing Material
- High-performance neoprene rubber impeller with marine-grade corrosion resistant metal components
- Warranty
- 1 Year (for aftermarket versions)
- Other Technical Attributes
- Designed for improved flexibility across broad temperature ranges; provides higher flow rates and cooling protection
What’s in the Box
- 1 x Water Pump Impeller (47-89984Q5/47-89984T5/47-89984T6)
- 1 x Drive Key
- 1 x Gasket
- 1 x Wear Plate
- 1 x O-ring
- 1 x Face Seal
- 1 x Drain Plug Seal
- 1 x Water Pump Gasket
- 1 x Actuator Seal
- 1 x Face Seal Tool
Installation Notes
- Disconnect the negative battery cable to prevent accidental starting.
- Remove the lower unit (gearcase) from the outboard motor. Refer to your service manual for specific bolt locations.
- Unbolt and remove the water pump housing to access the impeller.
- Take note of the old impeller's vane direction before removing it, along with the old gaskets, seals, and wear plate.
- Thoroughly clean all mating surfaces, removing any old gasket material or corrosion.
- Install the new wear plate, gaskets, and seals from the kit. Lightly grease the new impeller and slide it into the housing while turning the driveshaft clockwise to seat the vanes correctly.
- Reinstall the water pump housing, ensuring all bolts are torqued to the manufacturer's specification.
- Reattach the lower unit to the outboard and reconnect the battery cable. Start the engine and verify a steady stream of water from the tell-tale outlet.
Troubleshooting & FAQ
How do I know if this impeller kit fits my Mercury outboard?
This kit is specifically for Mercury V6 (3.4L) and V8 (4.6L) 4-stroke outboards (175–450 HP) manufactured in 2019 or later with a serial number of 2B529482 or higher. Always confirm your engine's model, year, and serial number before purchasing.
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 water stream from the "telltale" outlet, or a melted water pump housing. Upon inspection, a worn impeller will have cracked, brittle, or permanently bent vanes.
How often should I replace my water pump impeller?
For preventative maintenance, it is recommended to inspect the impeller annually and replace it every 1 to 2 years (or every 100-200 hours of operation). More frequent replacement may be necessary if you operate in saltwater or sandy/silty conditions.
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
- Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
- Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
- Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.
Payment & Security
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