Water Pump Impeller – Fits Mercury/Mariner 15-50 HP (Replaces 47-85089 10, 821354A2)

$16.91 $27.00

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Water Pump Impeller – Fits Mercury/Mariner 15-50 HP (Replaces 47-85089 10, 821354A2) is backordered and will ship as soon as it is back in stock.

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Product Details

This aftermarket Water Pump Impeller is designed for a wide range of Mercury/Mariner 15-50 HP 2-Stroke & 4-Stroke engines from 1984–2006, as well as Force and select Chrysler/US Marine models. It ensures proper engine cooling by circulating water, preventing overheating and potential damage.

It serves as a direct replacement for Mercury part numbers 47-85089 10, 8M0024502, 850893, and Sierra 18-3057, among others, offering a reliable fit and performance equivalent to the original component.

Engineered as a direct OEM-equivalent replacement.
Constructed from durable, high-performance neoprene rubber.
Features a 6-blade design for efficient water circulation.

Part Number Matrix

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

Brand	Part Number
Mercury	47-85089 10 / 47-8508910 / 8508910
Mercury	8M0024502
Mercury	850893
Mercury	850892 / 8508920 / 8M0027792
Mercury	850891 / 85089
Sierra	18-3057
Force	0755466

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Mercury/Mariner owners: Please verify your engine's model, HP, and serial number range against the table to ensure a perfect match. Specific serial number cutoffs are critical for certain models.

For Chrysler/Force/US Marine owners: This impeller replaces Force part 0755466 and fits a variety of 15-50 HP 2-Stroke engines from 1984–1999.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
Mercury/Mariner	15 HP XD Bigfoot	15	2-Stroke	1984–2005	47-85089 10
Mercury/Mariner	18/20 HP XD	18/20	2-Stroke	1984–2005	47-85089 10
Mercury/Mariner	25 HP Seapro, Mara, Super15	25	2-Stroke	1984–2005	47-85089 10
Mercury/Mariner	25 HP 3-cylinder	25	2-Stroke	1997+	47-85089 10
Mercury/Mariner	25/30/40 HP 4-stroke	25-40	4-Stroke	1997–2006	47-85089 10
Mercury/Mariner	30 HP 2-cylinder	30	2-Stroke	1994–1998	47-85089 10	G053314 & UP
Mercury/Mariner	30 HP Jet	30	2-Stroke	1998+	47-85089 10	G590000 & UP
Mercury/Mariner	40 HP 2-cylinder	40	2-Stroke	1994–1998	47-85089 10	G053314 & UP
Mercury/Mariner	40 HP 3-cylinder	40	2-Stroke	1997–1998	47-85089 10
Mercury/Mariner	40 HP 4-Stroke Std.	40	4-Stroke	1997–1999	47-85089 10	G231123-G760299
Mercury/Mariner	40 HP 4-Stroke 2:1 Ratio	40	4-Stroke	1999+	47-85089 10	G760300-T408999
Mercury/Mariner	40/50 HP 3-cylinder	40/50	2-Stroke	1995–1999	47-85089 10	G531301 & UP
Mercury/Mariner	45 HP 4-Stroke Bodensee	45	4-Stroke	1997+	47-85089 10	G231123 & UP
Mercury/Mariner	50 HP 3-cylinder	50	2-Stroke	1998+	47-85089 10	G590000 & UP
Mercury/Mariner	50 HP 4-Stroke Std.	50	4-Stroke	1997+	47-85089 10	G231123 & UP
Mercury/Mariner	75 HP	75	2-Stroke	1999	47-85089 10
Mercury/Mariner	9.9-15 HP 4-Stroke	9.9-15	4-Stroke	1999+	47-85089 10	OG760300 & UP
Mercury/Mariner	15 HP Super, 18-25 HP	15-25	2-Stroke	1984+	47-85089 10	6443973 & UP
Mercury/Mariner	20-25 HP 2&3 Cyl	20-25	2-Stroke	1984+	47-85089 10	5705532 & UP
Chrysler/Force/US Marine	Various models	15-50	2-Stroke	1984–1999	47-850893	Compatible with Force impeller 0755466

Technical Specs

Product Type: Water Pump Impeller
Installation: Direct OEM replacement
Dimensions: 73 mm (diameter) x 16 mm (hub) x 12.6 mm (thickness)
Material: Neoprene rubber
Blade Configuration: 6 blades
Color: Black
Warranty: Varies by manufacturer (typically 1 year)

What’s in the Box

1 x Water Pump Impeller (replaces 47-85089 10 / 8508910 / 8M0024502)

Installation Notes

Disconnect the negative battery cable before beginning work.
Remove the lower unit (gearcase) from the outboard motor.
Locate and unbolt the water pump housing to expose the impeller.
Note the rotational direction of the old impeller's blades before removing it.
Clean any debris from the impeller housing and apply a light coat of marine grease or soapy water to the new impeller.
Install the new impeller, ensuring the blades curve in the correct rotational direction.
Reassemble the pump housing, reinstall the lower unit, and reconnect the battery. Test in water.

Troubleshooting & FAQ

How do I know if this impeller will fit my engine?

The most reliable method is to match your engine's model, horsepower, and year to the compatibility table. For many Mercury/Mariner models, you must also verify your engine’s serial number falls within the specified range. Cross-referencing your old part number with our Part Number Matrix is also a great verification step.

What are the signs of a failing water pump impeller?

Common symptoms include an engine temperature alarm, the engine running hotter than usual, or a weak or nonexistent stream of water from the "tell-tale" outlet. If you notice any of these signs, inspect your cooling system and impeller immediately.

How often should I replace my impeller?

As a general maintenance guideline, replace your impeller every 1-2 years or every 100-200 hours of operation, whichever comes first. This interval may be shorter if you frequently operate in sandy, silty, or saltwater environments.

Is it necessary to lubricate the impeller during installation?

Yes, applying a thin layer of marine-grade grease or soapy water to the inside of the pump housing and the impeller itself will ease installation and provide lubrication during the initial dry start-up, preventing damage.

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

p>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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