Water Pump Impeller Kit – Fits Mercury, Mariner, Force, Sears 6-15 HP (Replaces 46-42089A5)

$75.50 $120.00

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Water Pump Impeller Kit – Fits Mercury, Mariner, Force, Sears 6-15 HP (Replaces 46-42089A5) is backordered and will ship as soon as it is back in stock.

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Product Details

This Water Pump Impeller Kit provides a comprehensive solution for servicing the cooling system on a wide range of Mercury, Mariner, Force, and Sears 6–15 HP outboard motors. It is engineered for 2-stroke models from 1986 and up, and 4-stroke models from 1995 to 2004, offering a precise fit for standard (Non-Bigfoot) gear cases. Regular replacement of the water pump components is critical for preventing engine overheating and ensuring long-term reliability.

This kit serves as a direct interchange for several OEM and aftermarket part numbers, including Mercury 46-42089A5, 46-42089A4, and 46-42089A3, as well as GLM 12051 and SEI Marine 96-261-01K. All components are designed to meet or exceed original equipment specifications.

For use with standard gear cases only (Non-Bigfoot models).
Includes the essential impeller, housing, wear plate, gaskets, and seals for a complete overhaul.
Constructed from high-quality metal alloy aund durable neoprene rubber for a long service life.

Part Number Matrix

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

Brand	Part Number	Notes
Mercury	46-42089A5	Current part number. Supersedes 46-42089A4 and 46-42089A3.
Mercury	46-42089A4	Superseded by 46-42089A5.
Mercury	46-42089A3	Superseded by 46-42089A4.
GLM	12051	Aftermarket cross-reference.
SEI Marine	96-261-01K	Aftermarket cross-reference.

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Mercury and Mariner engines, verifying the serial number (S/N) is crucial for ensuring the correct fit. This kit is not compatible with Bigfoot models.

For Force and Sears engines, compatibility is currently verified for the 1998 model year. Other years may be compatible but are unconfirmed.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
Mercury/Mariner	Standard	6	2-Stroke	1986–up	46-42089A5	S/N 0A197112 and up
Mercury/Mariner	Standard	8	2-Stroke	1986–up	46-42089A5	S/N 0A197112 and up
Mercury/Mariner	Standard	9.9	2-Stroke	1986–up	46-42089A5	S/N 0A197112 and up
Mercury/Mariner	Standard	10	2-Stroke	1986–up	46-42089A5	XR10 models
Mercury/Mariner	Standard	15	2-Stroke	1988–up	46-42089A5	S/N 0B292414 and up
Mercury/Mariner	232CC	8	4-Stroke	1995–2004	46-42089A5	S/N 0G760300-0T178499
Mercury/Mariner	Non-Bigfoot	9.9	4-Stroke	1999–2004	46-42089A5	S/N 0G760300-0T979999
Mercury/Mariner	Non-Bigfoot	15	4-Stroke	1998–2004	46-42089A5	323CC, S/N 0G590000-1B727495
Force	Standard	9.9	2-Stroke	1998	46-42089A5	Also fits Sears models
Force	Standard	15	2-Stroke	1998	46-42089A5	Also fits Sears models
Sears	Standard	9.9	2-Stroke	1998	46-42089A5	Force-based models
Sears	Standard	15	2-Stroke	1998	46-42089A5	Force-based models

Technical Specs

Product Type: Water Pump Impeller Repair Kit
Installation: Standard Gear Case (Non-Bigfoot)
Material: Metal alloy and neoprene rubber
Housing Material: Finest quality metal alloy
Impeller Material: Neoprene rubber
Dimensions: 152 × 102 × 12.7 mm (6 × 4 × 0.5 in)
Weight: 0.3 kg (10.5 ounces)
OEM Application: Mercury/Mariner/MerCruiser/Force/Sears Outboard Motors
Package Type: Rebuild kit with multiple components
Other Technical Attributes: Compatible with standard gear cases only (Non-Bigfoot models)

What’s in the Box

1 x Impeller (47-42038-2)
1 x Wear Plate (42200)
1 x Gasket (27-19202)
1 x Gasket (27-19204-3)
1 x Gasket (12-19183)
1 x Gasket (19643)
1 x Pump Base (46-420T5)
1 x Pump Housing (46-42089A2)
1 x Retainer (42375)
2 x Oil Seal (26-41365-1)
2 x Seal (26-33613/26-42133)
1 x Screw (10-48408)
2 x Washer (12-16448)
1 x Quad Ring (25-822236)

Installation Notes

Disconnect the negative battery cable and shift linkage.
Remove the lower unit mounting bolts and carefully lower the gearcase to access the water pump.
Unbolt and remove the old water pump housing assembly, taking note of component orientation.
Thoroughly clean all mating surfaces, removing any old gasket residue.
Install the new seals, wear plate, gaskets, and impeller into the new housing. Lubricate new seals as needed.
Carefully assemble the new pump housing and secure it with the provided hardware to the recommended torque.
Reinstall the lower unit, ensuring the driveshaft, shift shaft, and water tube align correctly.
Reattach linkages, tighten all bolts to manufacturer specifications, and reconnect the battery. Test run the engine with a water supply.

Troubleshooting & FAQ

How do I confirm this kit fits my specific engine?

Your engine must be listed in the compatibility tables. For Mercury and Mariner models, it is critical to verify that your engine's serial number falls within the specified range. This kit is only compatible with standard gear cases and will not fit Bigfoot models.

What are the signs of a failing water pump impeller?

Common symptoms include the engine overheating, especially at idle or low speeds, a weak or intermittent water stream from the tell-tale outlet, or finding brittle, cracked, or melted blades on the old impeller during an inspection.

How often should I replace my water pump impeller?

As a crucial part of preventative maintenance, we recommend inspecting the impeller annually and replacing it every 1-2 years or 100-200 hours of use, whichever comes first. Replacement intervals should be shorter if operating in saltwater or debris-heavy water.

Is this a complete kit, or do I need other parts?

This is a comprehensive kit that includes all the standard wear parts for a water pump rebuild: the impeller, housing, base, wear plate, gaskets, seals, and associated hardware. No other components are typically needed for a standard service.

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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