Water Pump Impeller Kit with Housing – Fits MerCruiser Alpha & Bravo Engines
This comprehensive water pump impeller repair kit fits a wide range of MerCruiser Alpha and Bravo inboard engines equipped with a plastic one-piece body sea water pump. It is designed for V6 and V8 models, including 4.3L, 5.0L, 5.7L, 6.2L, 7.4L, and 8.2L engines.
This kit serves as a direct replacement for Mercury/MerCruiser 46-807151A14, Sierra 18-3150, and Mallory 9-48350, among others, ensuring a precise fit and reliable cooling performance.
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Complete Repair Kit: Includes the impeller, housing, wear plate, O-rings, quad ring, and all necessary bolts and washers for a full service.
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Specific Application: Engineered specifically for engine-mounted sea water pumps with a plastic one-piece body.
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Broad Compatibility: Covers numerous MerCruiser Alpha, Bravo, and performance series engines.
Part Number Cross-Reference
Use this table to confirm equivalent part numbers across OEM and aftermarket brands.
Brand |
Part Number |
Mercury/MerCruiser |
46-807151A14 |
Mercury/MerCruiser |
46-807151A7 / 807151A14 |
Sierra |
18-3150 / 18-3150-1 |
Quicksilver |
807151A14 |
Mallory |
9-48350 |
Compatible Engine Models
Confirm your engine model/year in the table below. For Mercury owners, here’s a guide to help you identify your engine’s serial/model: Mercury Serial Number Guide. You can also review exploded diagrams to verify part numbers: Mercury Parts Diagrams & Catalog.
Model |
Engine Type |
OEM Part No. |
Notes |
Alpha with FWC (closed cooling) and internal pump |
4.3L, 5.0L, 5.7L, 6.2L |
46-807151A14 |
|
Bravo |
4.3L, 5.0L, 5.7L, 6.2L, 7.4L, 8.2L |
46-807151A14 |
|
350 MAG Alpha/Bravo |
5.7L V8 |
46-807151A14 |
|
357 MAG Bravo 4V/Alpha 4V |
5.8L V8 |
46-807151A14 |
|
383 MAG |
6.3L V8 |
46-807151A14 |
|
454/502 MPI MAG Bravo |
7.4L/8.2L V8 |
46-807151A14 |
|
575 SCI, 662 SCi, 600 SCi, 700 SCi |
Performance V8 |
46-807151A14 |
|
350/6.2L Black Scorpion SKI |
5.7L/6.2L V8 |
46-807151A14 |
|
500 CARB (502CID) |
8.2L V8 |
46-807151A14 |
|
5.7L Tow Sport |
5.7L V8 |
46-807151A14 |
|
Scorpion 377 |
6.2L V8 |
46-807151A14 |
|
500, 525, 565 EFI |
Performance V8 |
46-807151A14 |
|
540 Stroker 4V |
Performance V8 |
46-807151A14 |
|
5.7L Competition SKI engine (GEN +) |
5.7L V8 |
46-807151A14 |
|
Technical Specifications
Specification |
Value |
Product Type |
Water Pump Impeller Kit with Housing |
Installation |
Engine-mounted sea water pump |
Housing Material |
Plastic (one-piece body) |
Other Technical Attributes |
For plastic 1-piece body sea water pumps |
Bolt Torque Specification |
17 ft-lbs |
Warranty |
1 Year |
Package Contents
This kit includes all components required for a complete water pump overhaul.
- 1 x Water Pump Housing/Assembly (Replaces 46-807151A1)
- 1 x Impeller (Replaces 47-59362T1)
- 1 x O-Ring (Replaces 25-33465 / 25-8M0214925)
- 1 x Quad Ring (Replaces 25-94288 / 25-8M0215007)
- 1 x Wear Plate, Outer (Replaces 94576 / 8M0204674)
- 5 x Screws, Hex Head .312-18 x 3.250 (Replaces 10-74191 / 8M0204669)
- 2 x Screws, Hex Head .312-18 x 2.68 (Replaces 10-807356)
- 5 x Washers, .344 x .688 x .065 Stainless Steel (Replaces 12-814806)
Installation Guide
Follow these steps for a successful installation. Professional installation is recommended.
- Disconnect the negative battery cable to ensure safety.
- Close the seacock (if equipped) and drain the existing seawater cooling system.
- Loosen the hose clamps and remove the hoses from the water pump housing.
- Unscrew the mounting bolts and carefully remove the old pump assembly from the engine.
- Clean the mounting surface on the engine, ensuring it is free of old gasket material or debris.
- Assemble the new kit: place the new wear plate and impeller inside the new housing. Use a suitable lubricant on the impeller.
- Install the new O-rings/seals onto the pump housing.
- Mount the new water pump assembly onto the engine.
- Thread the new bolts and washers by hand, then tighten them evenly in a star pattern to the specified torque of 17 ft-lbs. Do not overtighten.
- Reconnect the water hoses and secure the clamps.
- Open the seacock, reconnect the battery cable, start the engine, and immediately check for proper water flow and leaks.
Troubleshooting & FAQ
Q: How do I know if this kit fits my MerCruiser engine?
A: This kit is for MerCruiser Alpha and Bravo engines with a plastic one-piece body sea water pump. It is not for engines with a solid plate front mount. Please verify your engine model against the compatibility list and ensure your current pump is a one-piece plastic design.
Q: What are the signs of a failing water pump impeller?
A: Common signs include the engine overheating at idle or low speeds, a weak water stream from the tell-tale outlet, and visible cracks, stiffness, or damage on the old impeller's vanes upon inspection.
Q: How often should the impeller be replaced?
A: It's recommended to inspect the impeller annually and replace it every 1-2 years or every 100-200 hours of use, whichever comes first. Replacement frequency should be increased in saltwater or silty conditions.
Q: OEM vs. Aftermarket?
A: This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.
Q: How fast do you ship and how much does it cost?
A: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.
Q: What is your warranty and return policy?
A: This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.
Important Notes
- Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
- This product is an aftermarket replacement part and is not an OEM component.
- Professional installation is recommended to ensure safety and optimal performance.
Why Choose JLM MARINE?
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Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
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Fast Global Shipping: Free delivery worldwide in 5–15 days.
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Direct from Manufacturer: Competitive pricing without compromising quality.