Water Pump Impeller – Fits Mercury/MerCruiser V6 & V8 4.3L-8.2L Engines (Replaces 47-862232A2, 18-3016-1)
Water Pump Impeller – Fits Mercury/MerCruiser V6 & V8 4.3L-8.2L Engines (Replaces 47-862232A2, 18-3016-1) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Water Pump Impeller – Fits Mercury/MerCruiser V6 & V8 4.3L-8.2L...
Product Details
This is a replacement Water Pump Impeller – Fits Mercury/MerCruiser V6 & V8 4.3L-8.2L Engines used in the raw water cooling system. It is designed for a broad range of gasoline MerCruiser sterndrive engines, including V6 models from 4.3L to 4.5L and V8 models from 5.0L up to 8.2L displacement.
This impeller directly replaces Mercury part numbers 47-862232A2 and 18-3016-1, as well as aftermarket equivalents from HeuroFosh (18-3016-1) and JLM Marine (18-3016-1).
- Installs via a direct press-fit on the pump shaft.
- Engineered for use in raw water cooling systems.
- Package contains one impeller.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury | 47-862232A2 |
| Mercury | 18-3016-1 |
| HeuroFosh | 18-3016-1 |
| JLM Marine | 18-3016-1 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For MerCruiser models, pay close attention to engine displacement (liters), model names (e.g., MPI, MAG), and serial number ranges where specified, as these are critical for ensuring correct fitment.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| MerCruiser | 4.3L MPI | Various | 4-Stroke | All | 47-862232A2/18-3016-1 | V6 Engine |
| MerCruiser | 5.0L/350 MAG | Various | 4-Stroke | 0M300000 and above | 47-862232A2/18-3016-1 | V8 Engine |
| MerCruiser | 5.7L/377 MAG | Various | 4-Stroke | 0M300000 and above | 47-862232A2/18-3016-1 | V8 Engine |
| MerCruiser | 6.2L MPI | Various | 4-Stroke | 0M300000 and above | 47-862232A2/18-3016-1 | V8 Engine, Black Scorpion became SmartCraft compatible at serial #0M391777 |
| MerCruiser | 4.5L | 200-250 HP | 4-Stroke | All | 47-862232A2/18-3016-1 | V6 Engine |
| MerCruiser | 6.2L | 300-370 HP | 4-Stroke | All | 47-862232A2/18-3016-1 | V8 Engine |
| MerCruiser | 496/8.1L | Various | 4-Stroke | All | 47-862232A2/18-3016-1 | V8 Engine |
| MerCruiser | 8.2L | Various | 4-Stroke | All | 47-862232A2/18-3016-1 | V8 Engine |
Technical Specs
- Product Type
- Water Pump Impeller
- Installation
- Direct replacement
- Fuel Type
- Gasoline
- Connection
- Press-fit on pump shaft
- Housing Color
- Black rubber
- Fitting Type
- Press-fit
- Other Technical Attributes
- Raw water cooling system component
What’s in the Box
- 1 x Water Pump Impeller (47-862232A2/18-3016-1)
Installation Notes
- Disconnect the boat's battery and close the raw water intake seacock.
- Locate the raw water pump, typically on the front of the engine, and place a container beneath it to catch spills.
- Remove the screws holding the pump's front cover plate.
- Carefully pull out the old impeller using pliers or an impeller puller tool. Note the direction the blades are bent.
- Clean the interior of the pump housing and the cover plate, ensuring both surfaces are smooth and free of debris or scoring.
- Gently lubricate the new impeller with a water-based lubricant or dish soap.
- Insert the new impeller into the housing, bending the blades in the same direction as the old one. This should match the engine's rotation.
- Reinstall the cover plate with a new gasket (if required and purchased separately) and tighten the screws evenly.
- Open the seacock and reconnect the battery.
- Start the engine and immediately check for water flow from the exhaust and for any leaks around the pump housing.
Troubleshooting & FAQ
How do I know if this impeller fits my MerCruiser engine?
Check your engine model and displacement against our "Engine & Model Compatibility" table. This impeller fits a wide range of V6 (4.3L, 4.5L) and V8 (5.0L-8.2L) engines. For 5.0L/350 MAG and larger engines from the mid-2000s, it generally fits models with serial numbers 0M300000 and above.
What are the signs of a failing water pump impeller?
The most common symptom is engine overheating, especially at idle or low speeds. Other signs include a reduced or absent stream of water from the tell-tale outlet, a 'whining' noise from the pump area, or visible cracks, stiffness, and damage to the impeller blades upon inspection.
How often should I replace my impeller?
As a rule of thumb for preventative maintenance, inspect your impeller annually and replace it every 100-200 hours of engine operation or every 1-2 years, whichever comes first. This is crucial in saltwater or silty conditions.
What direction do the impeller blades bend during installation?
The blades must be bent to follow the natural rotation of the engine's driveshaft. Before removing the old impeller, crank the engine briefly (with intake closed) or turn it by hand to see which way the shaft spins. Install the new impeller with blades curved in the opposite direction of rotation, so they flex correctly once the engine starts.
Can I reuse my old pump housing?
You can reuse the housing if the interior surface is perfectly smooth and free of scoring, grooves, or corrosion. Any roughness or damage will shred a new impeller very quickly and should be addressed by replacing the housing.
Is a gasket or O-ring included?
This product listing is for the impeller only. Associated gaskets, seals, or o-rings must be purchased separately based on your specific water pump model's requirements.
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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