Water Pump Impeller Kit – Fits MerCruiser & Mercury/Mariner 40-250HP (Replaces 47-43026Q06, 8M0100526)

$23.00

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Water Pump Impeller Kit – Fits MerCruiser & Mercury/Mariner 40-250HP (Replaces 47-43026Q06, 8M0100526) is backordered and will ship as soon as it is back in stock.

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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 Water Pump Impeller Kit is an essential service part for maintaining the cooling system on a wide range of Mercury/Mariner outboards (40–250HP, 2-Stroke & 4-Stroke, from 1990 to present) and MerCruiser Alpha One Generation 2 sterndrives (serial number 0D469859 and above).

It serves as a direct replacement for Mercury part numbers 47-43026Q06, 8M0100526, 47-43026Q5, 47-43026T6, and Sierra equivalents 18-3214 and 18-3265, among others.

Engineered for direct-fit installation.
Constructed from durable stainless steel and high-performance neoprene rubber.
Features non-asbestos gaskets to ensure a reliable seal.

Part Number Matrix

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

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

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For MerCruiser sterndrives, this kit fits Alpha One Gen 2 models with serial numbers 0D469859 and newer.

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

For Mercury and Mariner outboards, check the comprehensive list below covering various 2-stroke and 4-stroke models.

Brand	Model	Rated HP	Stroke	Years	Notes
Mercury/Mariner	F40-60 BigFoot/Command Thrust	40-60	4-Stroke
Mercury/Mariner	BigFoot	60	2-Stroke	From S/N 0D000750
Mercury/Mariner	4-Stroke	75-115	4-Stroke
Mercury/Mariner	2-Stroke	70-90	2-Stroke	From S/N 0A996142
Mercury/Mariner	2-Stroke (4 Cylinder)	100-125	2-Stroke		Models with pump cover screws without insulators
Mercury/Mariner	V-200/225/250	200-250	2-Stroke		3.0L models
Mercury/Mariner	LZ150	150		2001 & up
Mercury/Mariner	PX150	150		1999
Mercury/Mariner	SX150	150		1999–2005
Mercury/Mariner	VX150	150		2000–2005
Mercury/Mariner	VZ150	150		2000 & up
Mercury/Mariner	Z150	150		2001 & up
Mercury/Mariner	Various	175		1992–2000
Mercury/Mariner	VZ175	175		2001 & up
Mercury/Mariner	Various	200		1992–1999
Mercury/Mariner	F200/LF200	200		2002 & up
Mercury/Mariner	L200	200		1992–1999
Mercury/Mariner	LX200	200		1999–2005
Mercury/Mariner	LZ200	200		2000 & up
Mercury/Mariner	SX200	200		1999–2005
Mercury/Mariner	VX200	200		2000–2005
Mercury/Mariner	VZ200	200		2001 & up
Mercury/Mariner	Z200	200		2000 & up
Mercury/Mariner	F225/F225	225		2002 & up
Mercury/Mariner	VX225	225		2000–2005
Mercury/Mariner	LZ250	250		2003 & up
Mercury/Mariner	VX250	250		2002–2005
Mercury/Mariner	Z250	250		2003 & up
Mercury/Mariner	LZ300	300		2003 & up
Mercury/Mariner	Z300	300		2003 & up
Mercury/Mariner	Z300 (6D0)	300		2003 & up

Technical Specs

Product Type: Water Pump Impeller Kit
Installation: Direct replacement
Housing Material: Stainless steel, neoprene rubber
Housing Color: Black/metallic
Weight: 189g (6.7 oz)
Other Technical Attributes: Non-asbestos gasket materials

What’s in the Box

This comprehensive kit includes the following core components:

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)

Note: Some kit variations from different aftermarket sources may also include a wear plate, o-rings, a grommet, and washers. The core components listed above are always included.

Installation Notes

Disconnect the battery before starting work.
Remove the lower unit (outboard) or sterndrive from the transom assembly.
Unbolt and remove the water pump housing assembly. Note the orientation of the old parts.
Remove the old impeller, gaskets, and wear plate, cleaning any debris or corrosion from the housing surfaces.
Install the new wear plate and gaskets.
Slide the new impeller onto the driveshaft, turning the shaft clockwise to bend the vanes correctly. Ensure the keyway is aligned.
Reinstall the water pump housing and torque bolts to manufacturer specifications.
Re-install the lower unit/sterndrive with new gaskets where required.
Reconnect the battery and test the engine's cooling system at the boat ramp, ensuring a steady stream of water from the tell-tale port.

Troubleshooting & FAQ

How do I confirm this kit fits my specific engine?

The best way is to match your engine's model, serial number, and year to the compatibility tables provided. For MerCruiser Alpha One Gen 2 drives, the serial number is the key identifier (0D469859 and above). For outboards, check both the model/HP and any serial number breaks noted in the list.

What are the signs of a failing water pump impeller?

Common symptoms include a weak or non-existent water stream from the "tell-tale" outlet, engine overheating alarms, and in severe cases, steam from the exhaust. Reduced cooling performance can cause catastrophic engine damage if ignored.

How often should I replace the impeller?

As a general maintenance rule, it's recommended to replace the impeller every 1-2 years or every 100-200 hours of use, whichever comes first. Usage in saltwater or sandy/murky conditions may require more frequent replacement.

Why is my engine overheating after installing the new impeller?

Possible causes include: incorrect installation (e.g., impeller vanes bent in the wrong direction), a blockage in the cooling water passages, a faulty thermostat, or a worn-out pump housing that was not replaced. Always ensure the impeller key is properly installed to lock the impeller to the driveshaft.

Can I just replace the rubber impeller and not the whole kit?

It is strongly recommended to replace the full kit, including the wear plate and gaskets. The plate can become scored over time, and old gaskets can become brittle, leading to leaks and reduced pump efficiency even with a new impeller.

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.

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