Water Pump Impeller Kit – Fits Mercury/Mercruiser Alpha 1 Gen 2 & Outboards 40-250 HP (Replaces 47-43026Q06)

$22.80

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Water Pump Impeller Kit – Fits Mercury/Mercruiser Alpha 1 Gen 2 & Outboards 40-250 HP (Replaces 47-43026Q06) is backordered and will ship as soon as it is back in stock.

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

Free standard shipping on all orders under 1 KG

If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This comprehensive Water Pump Impeller Kit – Fits Mercury/Mercruiser Alpha 1 Gen 2 & Outboards 40-250 HP (Replaces 47-43026Q06) provides everything needed for a complete service on a wide range of Mercury-family engines. It is designed for Mercury/Mariner outboards from 40 to 250 HP (both 2-stroke and 4-stroke models) and Mercruiser Alpha One Gen 2 stern drives with serial numbers 0D469859 and above.

The kit serves as a direct interchange for Mercury part numbers 47-43026Q06, 47-8M0100526, 47-43026Q5, 47-43026T6/T7/T8/T10/T11, and Sierra equivalents 18-3214 and 18-3265.

Installation: Direct OEM replacement design for a hassle-free fit.
Durability: Features a high-quality neoprene rubber impeller for extended service life.
Warranty: Includes a 1-year warranty against manufacturing defects.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket suppliers.

Brand	Part Number
Mercury	47-43026Q06 / 47-8M0100526
Mercury	47-43026Q5
Mercury	47-43026T6 / T7 / T8 / T10 / T11
Sierra	18-3214
Sierra	18-3265

Engine & Model Compatibility

Confirm your engine model and serial number in the tables below.

For Mercury/Mariner Outboards: This kit fits a wide variety of 2-stroke and 4-stroke models. Due to inconsistencies in source data, some year ranges are not specified. Always verify your serial number and engine configuration.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
Mercury	F40-F60 Bigfoot/Command Thrust	40-60	4-Stroke		47-43026Q06
Mercury	60 HP Bigfoot	60	2-Stroke	S/N 0D000750+	47-43026Q06
Mercury	70-90 HP	70-90	2-Stroke	S/N 0A996142+	47-43026Q06
Mercury	75-115 HP	75-115	4-Stroke		47-43026Q06
Mercury	100-125 HP (4 cylinder)	100-125	2-Stroke		47-43026Q06	Models having pump cover screws without insulators
Mercury	150 EFI	150	4-Stroke		47-43026Q06
Mercury	V-200/225/250 (3.0L)	200-250	2-Stroke		47-43026Q06
Mercury	Verado 135-175 (4 cylinder)	135-175	4-Stroke	Various	47-43026Q06
Mercury	Verado 200-300 (6 cylinder)	200-300	4-Stroke	Various	47-43026Q06

For Mercruiser Stern Drives: Fits all Alpha One Generation 2 drives with serial numbers 0D469859 and higher.

Brand	Model	Years	OEM Part No.
Mercruiser	Alpha One Gen 2	S/N 0D469859+	47-43026Q06

Technical Specs

Product Type: Water Pump Impeller Repair Kit
Installation: Direct OEM replacement
Impeller Dimensions: 22.40mm (height) × 89.00mm (diameter) × 32mm (bore)
Weight: 189 grams (6.7 oz)
Impeller Material: High-quality neoprene rubber
Warranty: 1-year against manufacturing defects (aftermarket)

What’s in the Box

1 x Impeller (47-43026Q02)
1 x Impeller Plate (817276)
1 x Impeller Key (28-8M0032833)
1 x Seal Ring Gasket (26-45577)
1 x Impeller Gasket (27-817277)
1 x Face Seal and Tool (26-816575A2)
2 x O-Ring (25-21836)
2 x Drain Screw Gasket (26-830749)

Installation Notes

Disconnect the battery and shift the lower unit to neutral.
Remove the lower unit by unbolting it from the drive shaft housing. Disconnect any speedometer tube.
Place the lower unit on a workbench and remove the water pump housing cover bolts.
Slide the housing up and off the drive shaft to expose the old impeller assembly.
Remove the old impeller, key, gaskets, and plate. Thoroughly clean all mating surfaces of debris and old gasket material.
Install the new lower gasket, plate, key, and impeller. Use a small amount of marine grease or dish soap to lubricate the impeller and housing interior.
Rotate the drive shaft clockwise while pressing the new impeller down into the housing to correctly orient the vanes.
Install the face seal and upper gasket, then re-attach the water pump housing cover. Tighten bolts to the manufacturer-specified torque in a star pattern.
Reinstall the lower unit, ensuring the drive shaft, shift shaft, and water tube align correctly.
Reconnect the battery, attach a water supply (flushing muffs), and start the engine to verify strong water flow from the telltale port.

Troubleshooting & FAQ

How do I find my engine's serial number?

The serial number is typically found on a metal tag or sticker attached to the swivel bracket (the component that mounts the engine to the boat's transom) or on the engine block itself.

How do I know if this kit fits my Alpha One Gen 2 drive?

This kit is compatible with Mercruiser Alpha One Gen 2 stern drives with a serial number of 0D469859 or higher. Drives with lower serial numbers require a different kit.

What are the signs of a failing water pump impeller?

Common signs include a weak or non-existent water stream from the "telltale" indicator, engine overheating alarms, and reduced engine performance. Visible damage to the old impeller, such as cracked, brittle, or missing vanes, confirms it needs replacement.

How often should I replace the water pump impeller?

For preventative maintenance, it is recommended to replace the entire water pump kit every 1–2 years or every 100–200 hours of operation, whichever comes first. This interval should be shorter if operating in saltwater or high-debris environments.

Is this an OEM part?

This is an aftermarket replacement part, not an OEM component. It is built to meet or exceed OEM-level specifications with comparable materials and performance. Our parts are manufactured in an ISO 9002 facility and are batch-inspected for quality and consistency.

What is your shipping and return policy?

We ship worldwide, with typical transit times of 5–15 days for standard delivery. Standard shipping is free for most orders, with expedited options available at checkout. The kit is covered by a 1-year warranty against manufacturing defects under normal use. If you encounter an issue, please contact our support team with your order details. Returns are accepted within our standard window for unused items in their original condition.

Safety & Important Info

Verify images and specifications against your original part before purchase. If anything differs—even if your model appears compatible—do not install the part.
This is an aftermarket replacement component, not an original equipment manufacturer (OEM) part.
Professional installation is highly recommended for safety, proper function, and performance.

About Sea Sierra

Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and rigorously tested for real-world conditions.
Fast Global Fulfillment — We offer free standard delivery to most regions with a transit time of 5–15 days.
Manufacturer-Direct Value — Our parts provide fair pricing without compromising on materials or quality control.

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