Water Pump Impeller Kit – Fits Mercury/Mariner 135/150 HP 4-Stroke (Replaces 46-8M0061040)
Water Pump Impeller Kit – Fits Mercury/Mariner 135/150 HP 4-Stroke (Replaces 46-8M0061040) 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 – Fits Mercury/Mariner 135/150 HP 4-Stroke ...
Water Pump Impeller Kit – Fits Mercury/Mariner 135/150 HP 4-Stroke (Replaces 46-8M0061040) is backordered and will ship as soon as it is back in stock.
Product Details
This Water Pump Impeller Kit – Fits Mercury 135/150 HP EFI 4-Stroke (Replaces 46-8M0061040) is designed for Mercury and Mariner 135–150 HP 4-Stroke outboards, offering coverage for various FourStroke EFI engines. It serves as a direct-fit replacement to restore your engine's cooling system performance.
This kit provides a direct replacement for Mercury OEM part number 46-8M0061040.
- Engineered for direct replacement installation.
- Complete repair kit for Mercury outboard cooling systems.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury | 46-8M0061040 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Mercury/Mariner models, this kit fits select 4-stroke EFI outboards. Verify your specific model and part number before ordering.
| Brand | Model | Rated HP | Stroke | OEM Part No. | Notes |
|---|---|---|---|---|---|
| Mercury | F150 | 150 | 4-Stroke | 46-8M0061040 | EFI model |
| Mercury | F135 | 135 | 4-Stroke | 46-8M0061040 | EFI model |
| Mercury | F75-115 | 75-115 | 4-Stroke | 46-8M0061040 | 1.7L EFI models |
Technical Specs
- Product Type
- Water Pump Impeller Kit
- Installation
- Direct replacement
- Other Technical Attributes
- Water pump repair kit designed for Mercury outboard cooling systems
What’s in the Box
- Impeller
- Gaskets
- Wear Plate
- Key Way
- Shaft Seal
Installation Notes
- Disconnect the battery and remove the engine cowling.
- Place a drain pan under the lower unit and remove the gearcase oil drain/fill screws to drain the oil.
- Remove the bolts securing the lower unit (gearcase) to the midsection.
- Carefully lower and remove the gearcase from the outboard.
- Unbolt and lift the water pump housing to expose the impeller.
- Remove the old impeller, gaskets, wear plate, and key way from the driveshaft.
- Thoroughly clean all mating surfaces, removing any old gasket material or debris.
- Install the new wear plate, gaskets, and key way.
- Slide the new impeller onto the driveshaft, turning the shaft clockwise to help seat the impeller vanes correctly inside the housing.
- Reinstall the water pump housing and torque the bolts to the manufacturer's specified values.
- Reattach the gearcase to the outboard, ensuring the driveshaft and shift shaft align, and refill with fresh gear oil.
- Connect a water supply to the engine, start it, and verify a strong, consistent water stream from the tell-tale outlet.
Troubleshooting & FAQ
How do I confirm this kit fits my engine?
This kit is for specific Mercury/Mariner 135HP, 150HP, and select 75-115HP 4-Stroke EFI models. The most reliable method is to match your engine's required part number to 46-8M0061040. Always check the compatibility table and your original part before ordering.
What are the signs of a failing water pump impeller?
Key symptoms include the engine overheating at idle or low speeds, a weak or intermittent water stream from the "telltale" outlet, or in severe cases, a complete lack of water discharge, which can quickly lead to engine damage.
How often should I replace my outboard's impeller?
For preventative maintenance, 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 helps prevent unexpected cooling system failures.
Is this a difficult part to install?
Installation requires removing the lower unit (gearcase), which can be complex. While it is manageable for individuals with strong mechanical skills and the right tools, we recommend professional installation to ensure proper sealing and function, protecting your engine from overheating.
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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