Water Pump Impeller Kit with Housing – Fits Mercury/Mariner 30-70 HP (Replaces 46-77177A3, 77177A3)
Water Pump Impeller Kit with Housing – Fits Mercury/Mariner 30-70 HP (Replaces 46-77177A3, 77177A3) 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.
U.S. orders usually arrive within 6–15 days, depending on stock location and destination.
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Water Pump Impeller Kit with Housing – Fits Mercury/Mariner 30-70 H...
Water Pump Impeller Kit with Housing – Fits Mercury/Mariner 30-70 HP (Replaces 46-77177A3, 77177A3) is backordered and will ship as soon as it is back in stock.
Product Details
This complete Water Pump Impeller Kit with Housing is designed for Mercury and Mariner 30-70 HP 2-stroke outboard engines manufactured between 1977 and 1997. It ensures your engine's cooling system functions efficiently by providing all necessary components for a full replacement, protecting the engine from overheating and costly damage.
The kit serves as a direct replacement for multiple part numbers, including Mercury 46-77177A3 and 77177A3, Sierra 18-3324, GLM 12100, and Tutorautomotive 46-01115, offering a reliable and cost-effective alternative to OEM parts.
- Engineered for direct OEM replacement and fitment.
- Includes a durable neoprene rubber impeller for robust performance.
- A comprehensive kit containing the housing, gaskets, O-rings, and plates for a complete overhaul.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket brands.
| Brand | Part Number |
|---|---|
| Mercury | 46-77177A3 / 77177A3 |
| Sierra | 18-3324 |
| GLM | 12100 |
| Tutorautomotive | 46-01115 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This kit is specifically designed for various Mercury and Mariner outboard engines. Ensure your model and serial number range match the specifications for proper fitment.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury | Outboard | 30 | 2-Stroke | 1977–1989 | 46-77177A3 | Serial #1271884-1448139 |
| Mercury | Jet | 30 | 2-Stroke | 46-77177A3 | Serial #C159200-G589999 | |
| Mercury/Mariner | Outboard | 35 | 2-Stroke | 1984–1989 | 46-77177A3 | 2 Cylinder (S/N 6445653 & Up) |
| Mercury/Mariner | Outboard | 40 | 2-Stroke | 1978–1979 | 46-77177A3 | 2 Cylinder (S/N 4860103-5556229) |
| Mercury/Mariner | Outboard | 40 | 2-Stroke | 1980–1983 | 46-77177A3 | 2 Cylinder (S/N 5556230-6445653) |
| Mercury/Mariner | Outboard | 40 | 2-Stroke | 1989–Up | 46-77177A3 | 4 Cylinder (S/N 0C159200 & Up) |
| Mercury/Mariner | Outboard | 45 | 2-Stroke | 1986–Up | 46-77177A3 | 4 Cylinder (S/N 5531630 & Up) |
| Mercury/Mariner | Outboard | 50 | 2-Stroke | 1978–1985 | 46-77177A3 | 4 Cylinder (S/N 4962056 & Up) |
| Mercury/Mariner | Outboard | 50 | 2-Stroke | 1984–1990 | 46-77177A3 | 3 Cylinder (S/N 6428681-0D000749) |
| Mercury/Mariner | Outboard | 60 | 2-Stroke | 1984–1990 | 46-77177A3 | 3 Cylinder (S/N 6428681-0D000749) |
| Mercury/Mariner | Outboard | 65 | 2-Stroke | 1976 | 46-77177A3 | 3 Cylinder (S/N 4382057-4571651) |
| Mercury/Mariner | Outboard | 70 | 2-Stroke | 1979–1983 | 46-77177A3 | 3 Cylinder (S/N 4977157-6428680) |
Technical Specs
- Product Type
- Water Pump Impeller Kit with Housing
- Installation
- Direct OEM replacement
- Impeller Material
- Neoprene rubber compound
- Warranty
- Varies by manufacturer (aftermarket warranties may apply)
What’s in the Box
- 1 x Water Pump Impeller (47-89983/18-3007)
- 1 x Upper Pump Housing (46-77822A1/18-3118)
- 1 x Water Pump Base (46-77177A1)
- 2 x Plate (27-32770/27-19551)
- 2 x Drain Gasket (12-20260/12-19183)
- 1 x Drain Plug (12-49221)
- 3 x Water Pump Base Gasket (27-32771/27-77417/27-19552)
- 3 x O-Ring (25-26855/25-45711/25-26722)
Installation Notes
- Disconnect the battery and shift the outboard into neutral.
- Remove the lower unit (gearcase) by unbolting it from the engine's midsection.
- Disassemble the water pump housing to access the old impeller and wear plate.
- Thoroughly clean all mating surfaces, removing any old gasket material or debris.
- Install the new gaskets, wear plate, and impeller. Ensure the impeller vanes are oriented correctly (typically by turning the driveshaft clockwise during installation).
- Install the new housing and torque the bolts to the manufacturer’s specification.
- Re-install the lower unit, ensuring the driveshaft, shift shaft, and water tube are correctly aligned.
- Once assembled, start the engine using a water supply (flushing muffs or in water) and verify a steady water stream from the tell-tale outlet.
Troubleshooting & FAQ
How can I be sure this kit will fit my engine?
The most reliable method is to check your engine's model, horsepower, and year against our compatibility table. For models with serial number ranges, verifying your engine's serial number is crucial for confirming an exact match.
What are the common signs of a failing water pump impeller?
The most common symptoms include the engine overheating at idle or low speeds, and a weak or absent stream of water from the tell-tale port. A brittle or cracked impeller discovered during inspection also indicates immediate need for replacement.
How often should I replace my water pump impeller?
As a general maintenance guideline, it is recommended to inspect the impeller annually and replace it every 1-2 years or every 100-200 hours of operation, whichever comes first. This interval can be shorter if you operate frequently in saltwater or sandy/silty conditions.
Is the pump housing always necessary to replace?
While the impeller is the most common failure point, the housing can become scored or warped from debris or impeller failure. Since this kit includes a new housing, it is best practice to replace it along with the impeller to ensure optimal pump pressure and longevity.
What is the difference between this aftermarket kit and an OEM one?
This aftermarket kit is designed to meet or exceed OEM specifications for fit, form, and function. The primary differences are the brand and price. We use high-quality materials, such as durable neoprene for the impeller, to ensure reliable performance at a better value.
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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