Water Pump Impeller – Fits Mercury Marine 40-60hp Outboards (Replaces 47-19453T)
Water Pump Impeller – Fits Mercury Marine 40-60hp Outboards (Replaces 47-19453T) is backordered and will ship as soon as it is back in stock.
Couldn't load pickup availability
Worry-free returns
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.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.
Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Water Pump Impeller – Fits Mercury Marine 40-60hp Outboards (Replac...
Product Details
This Sierra 18-8900 Water Pump Impeller – Fits Mercury Marine 40-60hp Outboards (Replaces 47-19453T) is engineered for Mercury, Mariner, and Force outboard engines. It is designed for a direct fit on Mercury/Mariner 40-60hp 3-cylinder outboards from 1991 and newer, including both standard and Big Foot models, ensuring reliable cooling performance.
This impeller serves as a direct replacement for multiple part numbers, including Mercury 47-19453T, 47-19453, and Mallory 9-45301.
- Installation: Designed for direct replacement of the original impeller.
- Material: Constructed from durable neoprene rubber for longevity in marine environments.
- Design: Features a 6-blade design to deliver consistent cooling system pressure.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury | 47-19453T |
| Mercury | 47-19453 |
| Mallory | 9-45301 |
| Mallory | 9-45301-10 |
| Sierra | 18-8900 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Mercury and Mariner models, please verify your engine's serial number or year range to ensure correct fitment. This impeller fits various 2-stroke and 4-stroke models.
For Force outboards, this part is compatible with select 50-60hp models.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury | 40 (EFI 4-stroke) | 40 | 4-Stroke | T409000 & Up | 47-19453T | 1.83:1 ratio |
| Mercury | 45 Jet | 45 | 3-Cylinder | D000750 & Up | 47-19453T | |
| Mercury | 50 (3-cyl) | 50 | 2-Stroke | D000750-G589999 | 47-19453T | |
| Mercury | 50 (4-stroke, 4-cyl) | 50 | 4-Stroke | T178500-T598999 | 47-19453T | Standard |
| Mercury | 50 (EFI 4-stroke) | 50 | 4-Stroke | T409000-B344398 | 47-19453T | Standard |
| Mercury | 55 (3-cyl) | 55 | 2-Stroke | D000750 & Up | 47-19453T | |
| Mercury | 60 (3-cyl) Standard | 60 | 2-Stroke | D000750 & Up | 47-19453T | |
| Mercury | 60 (4-stroke) Standard | 60 | 4-Stroke | OT178500-T598999 | 47-19453T | |
| Force | 50-60hp Models | 50-60 | 2-Stroke | Compatible | 47-19453T |
Technical Specs
- Product Type
- Water Pump Impeller
- Installation
- Direct replacement
- Material
- Neoprene rubber
- Blade Count
- 6 blades
- Dimensions
- Height: 24.6mm (31/32"), Diameter: 78.3mm (3 5/64")
- Shaft Diameter
- 19.2mm (3/4")
- Weight
- 44g (1.55 oz)
- Color
- Black
- Warranty
- Manufacturer's standard warranty
What’s in the Box
- 1 x Water Pump Impeller (47-19453T)
Installation Notes
- Disconnect the battery and remove the engine cover. Shift the outboard into the neutral position.
- Locate and remove the bolts securing the lower unit (gearcase) to the upper driveshaft housing.
- Carefully lower and remove the gearcase assembly from the outboard.
- Unbolt and lift the water pump housing cover to expose the old impeller. Note the orientation of the impeller blades.
- Remove the old impeller, sliding it off the driveshaft. Clean any debris from the housing.
- Install the new impeller, rotating the driveshaft clockwise to help bend the blades in the correct direction.
- Reassemble the water pump housing and reinstall the lower unit, ensuring all shafts and tubes align correctly.
- Once assembled, test the engine's cooling system with a water supply before heading out on the water.
Troubleshooting & FAQ
How do I know if this impeller is the right one for my motor?
The best way to confirm is by matching your engine's model, year, and serial number against the compatibility table provided. You can also match the OEM part number (e.g., 47-19453T) from your old part or service manual.
What are common signs that my impeller needs replacing?
Key signs include the engine overheating at idle or low speeds, a weak or non-existent stream of water from the "telltale" outlet, or a brittle or cracked appearance on the old impeller's blades during inspection.
How often should I replace my water pump impeller?
As a general maintenance rule, it is recommended to inspect your impeller annually and replace it every 1-2 years or every 100-200 hours of use, depending on operating conditions (e.g., saltwater vs. freshwater).
Is grease required for installation?
Yes, applying a light coat of marine-grade grease or a soap-and-water solution to the inside of the pump housing and the impeller blades can ease installation and provide initial lubrication upon startup.
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
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
