Water Pump Repair Kit – Fits Mercury/Mariner 3.9-9.8 HP Outboards (Replaces 47-89980T1, 89980Q1)

$27.99 $44.00

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Water Pump Repair Kit – Fits Mercury/Mariner 3.9-9.8 HP Outboards (Replaces 47-89980T1, 89980Q1) is backordered and will ship as soon as it is back in stock.

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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 aftermarket Water Pump Repair Kit is designed for a range of Mercury and Mariner outboard motors from 3.9 HP to 9.8 HP (model years 1979–1986). It is specifically engineered for engines equipped with a 0.438-inch impeller shaft, providing a reliable solution for restoring cooling system performance.

This kit serves as a direct replacement for Mercury part numbers 47-89980T1, 47-89980Q1, 89980T1, 89980Q1, and GLM 12271, ensuring a proper fit and function for routine maintenance or repair.

Installs in the lower unit gearcase assembly.
Features a durable CR Neoprene rubber impeller for longevity.
Includes all necessary seals, O-rings, and hardware for a complete service.

Part Number Matrix

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

Brand	Part Number
Mercury	47-89980T1
Mercury	47-89980Q1
Mercury	89980T1
Mercury	89980Q1
GLM	12271

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Mercury/Mariner models, compatibility is determined by model, year, and serial number. Always verify your specific serial number against the ranges provided in the table to ensure an exact match.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
Mercury/Mariner	Made in USA	4 (1-Cyl)	2-Stroke	1982–1986	47-89980T1	Serial Range: 5595532-0A809600
Mercury/Mariner	Made in USA	4.5 (1-Cyl)	2-Stroke	1980–1985	47-89980T1	Serial Range: 5595532 & Up
Mercury/Mariner	Made in USA	7.5	2-Stroke	1979–1986	47-89980T1	Serial Range: 5206550 & Up
Mercury/Mariner	Made in USA	9.8	2-Stroke	1979–1985	47-89980T1	Serial Range: 5206550 & Up
Mercury/Mariner	Made in CAN	4 (1-Cyl)	2-Stroke	1982–1986	47-89980T1	Serial Range: 7143688 & Up
Mercury/Mariner	Made in CAN	4.5 (1-Cyl)	2-Stroke	1980–1985	47-89980T1	Serial Range: 7147238 & Up
Mercury/Mariner	Made in CAN	7.5	2-Stroke	1979–1986	47-89980T1	Serial Range: 7125388 & Up
Mercury/Mariner	Made in CAN	9.8	2-Stroke	1979–1985	47-89980T1	Serial Range: 7125388 & Up
Mercury/Mariner	Made in BEL	4 (1-Cyl)	2-Stroke	1982–1986	47-89980T1	Serial Range: 9258281-9477829
Mercury/Mariner	Made in BEL	4.5 (1-Cyl)	2-Stroke	1980–1985	47-89980T1	Serial Range: 9258281 & Up
Mercury/Mariner	Made in BEL	7.5	2-Stroke	1979–1986	47-89980T1	Serial Range: 9217756 & Up
Mercury/Mariner	Made in BEL	9.8	2-Stroke	1979–1985	47-89980T1	Serial Range: 9217756 & Up
Mercury/Mariner	Made in AUS	4 (1-Cyl)	2-Stroke	1982–1986	47-89980T1	Serial Range: 8068065 & Up
Mercury/Mariner	Made in AUS	4.5 (1-Cyl)	2-Stroke	1980–1985	47-89980T1	Serial Range: 8068065 & Up
Mercury/Mariner	Made in AUS	7.5	2-Stroke	1979–1986	47-89980T1	Serial Range: 8057545 & Up
Mercury/Mariner	Made in AUS	9.8	2-Stroke	1979–1985	47-89980T1	Serial Range: 8057545 & Up

Technical Specs

Product Type: Water Pump Repair Kit
Installation: Lower Unit Gearcase
Impeller Material: CR Neoprene Rubber
Impeller Insert Size: 0.438 inch (11.13 mm)
Housing Material: Marine Grade Components
Dimensions: 10.5" L × 8.5" W × 1.5" H (package dimensions)
Weight: 62g (package weight)
Warranty: Varies by manufacturer (see source)
Other Technical Attributes: Aftermarket replacement for OEM Mercury/Mariner parts

What’s in the Box

1 x Impeller with 0.438" insert size (47-89980)
1 x Cartridge/Wear Plate (700-12560)
1 x Key, Woodruff Impeller
1 x Sleeve, guide water inlet tube (700-12963)
1 x Seal (700-85651)
2 x O-rings (700-81230, 700-81090)

Installation Notes

Disconnect the spark plug leads and battery for safety.
Place a drain pan under the gearcase and remove drain/fill screws to empty the oil.
Unbolt and carefully lower the gearcase from the driveshaft housing.
Remove the water pump housing bolts to access the impeller assembly.
Take note of the old impeller vane direction before removing it, along with the key, wear plate, and seals.
Clean all mating surfaces thoroughly, removing any old gasket material or corrosion.
Install the new components from the kit. Lightly grease the housing interior and ensure the impeller vanes are oriented correctly during insertion.
Reassemble the pump housing, torque bolts to manufacturer specifications, and reinstall the lower unit.
Refill the gearcase with fresh marine lubricant before starting the engine.
Test operation in water (submerged or with a flush attachment) to confirm steady water flow from the tell-tale port.

Troubleshooting & FAQ

How do I know if this kit fits my outboard?

This kit fits specific Mercury/Mariner 3.9-9.8 HP models from 1979–1986. The most critical factor is the impeller driveshaft diameter, which must be 0.438 inches. Please use the compatibility table and verify your engine's model, year, and serial number range before ordering.

What are the signs of a failing water pump impeller?

Common symptoms include the engine overheating at idle or low speeds, a weak or non-existent water stream from the "tell-tale" outlet port, and in some cases, a high engine temperature alarm. An impeller that is cracked, brittle, or has missing vanes cannot provide adequate cooling pressure.

How often should a water pump impeller be replaced?

As a general maintenance guideline, it is recommended to inspect and likely replace the impeller every 1-2 years or every 100-200 hours of use, whichever comes first. This interval can be shorter if you operate frequently in sandy, silty, or saltwater conditions.

What is the difference between part numbers 47-89980T1 and 47-89980Q1?

These are part numbers for the same kit. The "T" and "Q" suffixes often indicate revisions, packaging changes, or supersede an older part number. They are fully interchangeable, and this aftermarket kit is designed to replace all listed equivalents.

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

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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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