Water Pump Impeller – Fits Mercury/MerCruiser 40-100HP (Replaces 47-43026T2, 47-43026Q02)
Water Pump Impeller – Fits Mercury/MerCruiser 40-100HP (Replaces 47-43026T2, 47-43026Q02) 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
Product Details
This replacement Water Pump Impeller – Fits Mercury/MerCruiser 40-100HP (Replaces 47-43026T2, 47-43026Q02) is a crucial component for maintaining engine cooling systems. It is engineered for a broad range of Mercury Outboard 4-Stroke engines from 40 to 100 HP (1999–Present) and MerCruiser Alpha One Gen II stern drive applications (1991–Present), ensuring reliable performance and fitment.
It serves as a direct interchange for multiple OEM and aftermarket part numbers, including Mercury 47-43026T2, 47-43026Q02, 8M0025709, and Sierra 18-3056.
- Features a durable neoprene rubber construction for longevity in marine environments.
- Designed with a Key Drive system for secure installation and efficient power transfer.
- Package includes the impeller and installation key for a complete replacement.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury | 47-43026T2 |
| Mercury | 47-43026Q02 |
| Mercury | 8M0025709 |
| Mercury | 47-430262 |
| Mercury | 47-43026B2 |
| Sierra | 18-3056 |
| Sierra | 18-3056-10 |
| GLM | 89630 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This impeller is compatible with a range of 4-stroke Mercury outboard motors from 40 HP to 100 HP, primarily EFI models from 1999 to the present.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury | 40 | 40 | 4-Stroke | 1999–Present | 47-43026Q02/T2 | EFI models |
| Mercury | 50 | 50 | 4-Stroke | 1999–Present | 47-43026Q02/T2 | EFI models |
| Mercury | 60 | 60 | 4-Stroke | 1999–Present | 47-43026Q02/T2 | EFI models |
| Mercury | 65 | 65 | 4-Stroke | 1999–Present | 47-43026Q02/T2 | |
| Mercury | 70 | 70 | 4-Stroke | 1999–Present | 47-43026Q02/T2 | EFI models |
| Mercury | 75 | 75 | 4-Stroke | 1999–Present | 47-43026Q02/T2 | |
| Mercury | 80 | 80 | 4-Stroke | 1999–Present | 47-43026Q02/T2 | EFI models |
| Mercury | 90 | 90 | 4-Stroke | 1999–Present | 47-43026Q02/T2 | EFI models |
| Mercury | 100 | 100 | 4-Stroke | 1999–Present | 47-43026Q02/T2 | EFI models |
It is also specified for all MerCruiser Alpha One Gen II stern drive applications produced since 1991.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| MerCruiser | Alpha One Gen II | Various | 4-Stroke | 1991–Present | 47-43026T2 | Stern Drive |
Technical Specs
- Product Type
- Water Pump Impeller
- Installation
- Key Drive
- Material
- Neoprene Rubber
- Outer Diameter
- 88.4 mm
- Shaft Diameter
- 22.4 mm
- Depth/Height
- 32.5 mm
- Number of Blades
- 6
- Color
- Black
- Weight
- 50 g (0.11 lb)
- Other Technical Attributes
- Key Drive installation system ensuring excellent drive and sealing performance
What’s in the Box
- 1 x Water Pump Impeller (47-43026T2/47-43026Q02)
- 1 x Key
Installation Notes
- Disconnect the battery and remove the engine cowling.
- Shift the engine into neutral and remove the lower unit (gearcase) by unfastening the mounting bolts.
- Locate and unbolt the water pump housing, typically secured with four bolts.
- Slide the old impeller off the driveshaft, carefully noting the direction of the blades.
- Clean the pump housing and inspect the wear plate and housing for scoring or damage. Replace if necessary.
- Lightly lubricate the interior of the pump housing and the new impeller with marine grease.
- Install the new key into the driveshaft and slide the new impeller on, turning the shaft clockwise to help seat the blades.
- Reassemble the pump housing with a new gasket and tighten the bolts to the manufacturer's specified torque.
- Reinstall the lower unit, ensuring the driveshaft, shift shaft, and water tube are properly aligned.
- Once assembled, connect a water supply and briefly run the engine to confirm water is pumping correctly from the tell-tale outlet.
Troubleshooting & FAQ
How do I know if this impeller fits my specific engine model?
The best way to confirm fitment is to check your engine's original part number. This impeller replaces Mercury part numbers 47-43026T2, 47-43026Q02, and others listed in the Part Number Matrix. Also, verify your engine model and year against our compatibility tables.
What are the signs of a failing water pump impeller?
Common symptoms include the engine overheating at idle or low speeds, a weak or non-existent water stream from the "tell-tale" outlet, and a melted water pump housing. The flexible blades can also become brittle and break off over time, causing blockages.
How often should I replace my engine's impeller?
As a general rule, impellers should be inspected annually and replaced every 1-2 years (or every 100-200 hours of use), regardless of visible wear. Preventive replacement is key to avoiding overheating and engine damage, especially for boats used in saltwater.
What is the difference between the 47-43026Q02 and 47-43026T2 parts?
While sources do not document a specific technical difference, part numbers 47-43026Q02 and 47-43026T2 are considered direct equivalents and are interchangeable for the applications listed.
Is the installation key required?
Yes. This impeller uses a key drive system. The included key locks the impeller to the driveshaft, ensuring it spins correctly to pump water. Do not install the impeller without it.
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.
