Water Pump Impeller Kit with Housing – Fits Mercury Marine/MerCruiser 30-250 HP (Replaces 817275A5, 817275Q05)

$47.98 $76.00

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Water Pump Impeller Kit with Housing – Fits Mercury Marine/MerCruiser 30-250 HP (Replaces 817275A5, 817275Q05) is backordered and will ship as soon as it is back in stock.

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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).

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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 with Housing is engineered for reliable performance in a wide range of marine engines. It is designed to fit Mercury Marine/MerCruiser 30–250 HP outboards and Alpha One Gen 2 stern drives from 1991 and newer, as well as Chrysler/Force 75–120 HP outboards from 1995–1999. The kit provides all necessary components for a complete overhaul of the water pump assembly, ensuring proper engine cooling.

It serves as a direct interchange for multiple OEM and aftermarket part numbers, including Mercury 817275A5/817275Q05, Sierra 18-3570, Mallory 9-48315, and GLM 12415.

Installs as a direct replacement component.
Features a durable stainless steel housing and a robust neoprene rubber impeller.
Includes all essential gaskets, seals, and o-rings for a complete installation.

Part Number Matrix

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

Brand	Part Number
Mercury	817275A5 / 817275A6 / 817275A4 / 817275T4 / 817275Q4 / 817275Q05
Sierra	18-3570 / 18-3147
Mallory	9-48315 / 9-48314
GLM	12415
Redline	RL3570

Engine & Model Compatibility

Confirm your engine model/year in the table below.

This kit fits a wide range of Mercury Marine/MerCruiser outboards, stern drives, and Bigfoot models from 1991 and up.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
Mercury	3.0L EFI	200	4-Stroke	0T750164-1B504988	817275A5	DFI and EFI models
Mercury	3.0L EFI	225	4-Stroke	0G760300-1B504988	817275A5	Carb, DFI, EFI, and Seapro/Marathon models
Mercury	3.0L EFI	250	4-Stroke	0G760300-1B504988	817275A5	EFI models
Mercury	3.0L EFI	250XB	4-Stroke	0G980600-0T800999	817275A5	EFI models
Mercury	225 PRO XS	225	4-Stroke	1B104549-1B426560	817275A5	DFI (3.0L) models
Mercury	Alpha One Gen 2	N/A	N/A	1991 and up	817275K05/817275Q05	Stern drives
Mercury	Bigfoot	40	4-Stroke	OT228407 and up	817275A1/A2	4-cylinder models
Mercury	Bigfoot Bodensee	45	4-Stroke	OG231123 and up	817275A1/A2
Mercury	Bigfoot	50	4-Stroke	OG231123-OT178499	817275A1/A2	935cc models
Mercury	Bigfoot	50	4-Stroke	OT178500 and up	817275A1/A2	996cc models
Mercury	Bigfoot	60	4-Stroke	OD000750 and up	817275A1/A2	3-cylinder models
Mercury	Standard	60	4-Stroke	OT178500 and up	817275A1/A2
Mercury	Jet	65	4-Stroke	OC283222 and up	817275A1/A2
Mercury	Standard	70	4-Stroke	OA996142 and up	817275A1/A2	3-cylinder models
Mercury	Standard	75	4-Stroke	OC222000 and up	817275A1/A2	3-cylinder models
Mercury	Standard	75	4-Stroke	OG960500 and up	817275A1/A2	4-stroke models
Mercury	Standard	80	4-Stroke	OA996142 and up	817275A1/A2	3-cylinder models
Mercury	Jet	80	4-Stroke	OD283222 and up	817275A1/A2
Mercury	Standard	90	4-Stroke	OA996142 and up	817275A1/A2	3-cylinder models
Mercury	Standard	90	4-Stroke	OG960500 and up	817275A1/A2	4-stroke models
Mercury	Standard	100	4-Stroke	OB209468 and up	817275A1/A2	4-cylinder models
Mercury	Standard	115	4-Stroke	OC100000 and up	817275A1/A2	4-cylinder models
Mercury	Standard	125	4-Stroke	OD283222 and up	817275A1/A2	4-cylinder models
Mercury	V-200	200	4-Stroke	OG386496 and up	817275A1/A2	DFI (3.0L) models
Mercury	V-225	225	4-Stroke	OD280813 and up	817275A1/A2	DFI (3.0L) Carb & EFI models
Mercury	V-225	225	4-Stroke	OD590000 and up	817275A1/A2	DFI models
Mercury	V-250	250	4-Stroke	OG129222 and up	817275A1/A2	EFI (3.0L) models

Also compatible with select Chrysler/Force 2-stroke outboards from the late 1990s.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.
Force	Standard	75	2-Stroke	1999	817275A5
Force	Standard	90	2-Stroke	1995–1999	817275A5
Force	Standard	120	2-Stroke	1995–1999	817275A5

Technical Specs

Product Type: Water Pump Impeller Kit with Housing
Installation: Direct replacement
Housing Material: Stainless Steel
Impeller Material: Neoprene Rubber
Gasket Material: Non-asbestos

What’s in the Box

1 x Carrier Seal (821759A4)
1 x Impeller (47-43026T2)
1 x Impeller Plate (8172761)
1 x Impeller Key (28-43037)
2 x O-Ring (25-21836)
1 x Seal Ring Gasket (26-45577B1)
1 x Face Seal and Tool (26-816575A2)
1 x Impeller Gasket (27-430331)
1 x Impeller Gasket (27-8172771)
1 x Drain Screw Gasket (12-191833)

Installation Notes

Disconnect the battery and shift the outboard into neutral.
Remove the lower unit (gearcase) by unbolting it from the engine leg.
Unbolt and remove the old water pump housing assembly from the driveshaft.
Clean the driveshaft and mating surfaces, ensuring they are free of old gasket material and corrosion.
Install the new gaskets, face seal, and woodruff key onto the driveshaft.
Lightly lubricate the inside of the new housing and the new impeller with marine grease.
Slide the new impeller onto the driveshaft, turning the shaft clockwise to seat the vanes correctly.
Install the new housing over the impeller and bolt it down securely, following torque specifications.
Reinstall the lower unit, reconnect the battery, and test the engine in water to verify cooling system operation.

Troubleshooting & FAQ

How do I confirm this kit fits my specific engine model?

Always verify your engine's model, year, and serial number against the compatibility tables provided. The serial number range is the most accurate way to confirm fitment. If you are unsure, check your engine's service manual or contact us with your engine details before purchasing.

What are the signs of a failing water pump impeller?

Common signs include the engine overheating at idle or low speeds, a weak or non-existent stream of water from the "tell-tale" outlet, and visible cracking or damage to the impeller vanes upon inspection.

How often should I replace my water pump 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, depending on usage conditions (e.g., saltwater vs. freshwater).

The kit includes a housing. Do I need to replace mine?

This kit is designed for a complete overhaul. It is best practice to replace the housing along with the impeller, especially if the old housing shows signs of scoring, melting, or corrosion. This ensures optimal sealing and performance.

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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