Water Pump Impeller Repair Kit with Housing – Fits Mercury/Mariner 30–70 HP, Replaces 46-77177A3 / 77177A3
Water Pump Impeller Repair 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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Water Pump Impeller Repair Kit with Housing – Fits Mercury/Mariner ...
Water Pump Impeller Repair 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 water pump impeller repair kit with housing is intended for selected Mercury and Mariner 2-stroke outboard applications in the 30–70 HP range. It combines the impeller, pump housing, gaskets, seals, face plate, insert, and key needed for a complete water-pump service. Confirm the engine model, year, serial number, and original pump components before ordering.
The kit is listed as a replacement for Mercury references 46-77177A3 and 77177A3. Other aftermarket references commonly associated with this application include Sierra 18-3324, GLM 12100, Mallory 9-48312, and EMP 46-01115. These references should be used together with the engine-specific fitment information below, not as a substitute for confirming the original part.
- Complete pump service: Includes the pump housing, neoprene impeller, face plate, insert, gaskets, seals, o-rings, and drive key listed in the package contents.
- Installation location: Installs in the lower unit or gearcase water-pump assembly.
- Replacement materials: The housing is identified as Nylon PA66 plastic and the impeller as neoprene rubber.
Part Number Matrix
Use these reference numbers as identification aids and verify the complete application before purchase.
| Brand | Part Number |
|---|---|
| Mercury | 46-77177A3 / 77177A3 |
| Sierra | 18-3324 |
| GLM | 12100 |
| Mallory | 9-48312 |
| EMP | 46-01115 |
Engine & Model Compatibility
The following applications are listed for this replacement kit. Mercury and Mariner fitment can vary by model configuration and serial number, so match the engine’s complete identification information before installation.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury | JET (3CYL) | 30 | 2-Stroke | 1989–1997 | 46-77177A3 | Serial range: 0C159200–0G589999; 9570790 and up |
| Mercury/Mariner | Various | 35 | 2-Stroke | 1984–1989 | 46-77177A3 | 2-cylinder applications; serial ranges 6445653 and up, and 209608 and up |
| Mercury/Mariner | Various | 40 | 2-Stroke | 1978–1983 | 46-77177A3 | 2-cylinder applications; serial range 5556230 and up |
| Mercury | Various | 40 | 2-Stroke | 1989 and up | 46-77177A3 | 4-cylinder applications; serial ranges 0C159200 and up, and 9570790 and up |
| Mercury | Various | 45 | 2-Stroke | 1986 and up | 46-77177A3 | 4-cylinder applications; serial range 5531630 and up |
| Mercury | Various | 50 | 2-Stroke | 1978–1985 | 46-77177A3 | 4-cylinder applications; serial range 4962056 and up |
| Mercury | Various | 50 | 2-Stroke | 1984–1990 | 46-77177A3 | 3-cylinder applications; serial ranges 6428681–0D000749 and 0A721308 and up |
| Mercury | Various | 60 | 2-Stroke | 1984–1990 | 46-77177A3 | 3-cylinder applications; serial ranges 6428681–0D000749 and 0A721308 and up |
| Mercury | Various | 65 | 2-Stroke | 1976 | 46-77177A3 | 3-cylinder applications; serial range 4382057–4571651 |
| Mercury | Various | 70 | 2-Stroke | 1977–1983 | 46-77177A3 | 3-cylinder applications; serial ranges 4977157–0B110053 and 5579017–6428680 |
Technical Specs
- Product Type
- Water pump impeller repair kit with housing
- Installation
- Lower unit / gearcase
- Housing Material
- Nylon PA66 plastic
- Housing Color
- Black
- Impeller Material
- Neoprene rubber
- Package Dimensions
- 156 × 102 × 53 mm (6.14 × 4.02 × 2.09 inches)
- Weight
- 0.22 kg (7.8 oz)
- Fitting Type
- Vehicle-specific fit
- Part Classification
- Aftermarket replacement
What’s in the Box
- 1 × Water Pump Housing (77822A1)
- 1 × Insert (48753)
- 1 × Impeller (89983T)
- 1 × Upper Water Pump Gasket (19551)
- 1 × Lower Water Pump Gasket (19553)
- 1 × Face Plate (32768)
- 2 × Gasket (19552)
- 1 × O-Ring (25-26722)
- 2 × Drain Plug Seal (26-830749)
- 2 × O-Ring (805726)
- 1 × Key (8M0032837)
- 1 × Rubber (25-20273)
- 1 × Shift Bracket Seal (37721001)
Installation Notes
- Disconnect the battery’s negative terminal before beginning work.
- Place a drain pan under the gearcase and remove the drain and fill screws to drain the gear lubricant.
- Remove the bolts securing the lower unit to the engine and carefully lower the gearcase.
- Remove the old water-pump housing assembly from the driveshaft.
- Clean the mating surfaces before installing the replacement gaskets.
- Install the key, impeller, face plate, and gaskets on the driveshaft. Twist the impeller in the direction of engine rotation during installation.
- Slide the replacement housing over the impeller assembly and secure it with the appropriate fasteners.
- Guide the driveshaft and water tube into position while reinstalling the lower unit.
- Refill the gearcase with the correct marine gear lubricant to the engine manufacturer’s specification.
- Reconnect the battery. Start the engine with an appropriate water supply and check for a strong, steady tell-tale stream.
Troubleshooting & FAQ
How do I know if my water pump needs replacing?
Common signs include overheating at idle or low speed, a weak or absent tell-tale stream, or an impeller that is brittle, cracked, deformed, or missing vanes. Inspect the pump whenever the lower unit is serviced.
What is the recommended replacement interval?
Inspect the impeller at least annually and replace it when wear, cracking, hardening, or vane damage is found. Operating conditions such as sand, silt, or saltwater may require more frequent service. Follow the engine manufacturer’s maintenance schedule where available.
My old pump housing is metal. Why is this one plastic?
This replacement kit uses a Nylon PA66 plastic housing. Housing material and appearance can differ from the original part, so compare the pump design and the complete application information before installation.
Why replace the complete kit instead of only the impeller?
The housing, face plate, gaskets, seals, and key also wear or deteriorate. Replacing the complete pump service kit helps address sealing and wear-surface problems that may remain when only the impeller is changed.
Is this an OEM part?
No. This is an aftermarket replacement kit intended for the applications and reference numbers listed on this page. Mercury and Mariner are mentioned only to identify compatible engine brands and reference applications.
How should I confirm fitment?
Compare the original pump housing, impeller, key, and gasket arrangement, then verify the engine brand, model, horsepower, stroke, year, cylinder configuration, and serial number. Do not rely on horsepower alone.
What are the shipping and return terms?
Shipping availability, delivery estimates, warranty coverage, and return eligibility depend on the order and destination. Review the current store policies at checkout or contact support before ordering if these terms are important to your purchase.
Safety & Important Information
- Verify the engine model, year, serial range, and original components before purchase.
- This is an aftermarket replacement, not an OEM component.
- Follow the engine manufacturer’s service procedures and use suitable lifting, draining, and flushing equipment.
- Professional installation is recommended if you are not experienced with outboard lower-unit service.
About Sea Sierra
- Marine replacement parts — Parts selected for common service and repair applications.
- Fitment-focused listings — Reference numbers and application details are provided to help you compare the replacement with your original part.
- Support when needed — Contact support with your engine model and serial information if you need help checking the listed application.
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