Water Pump Impeller Kit – Fits Mercury/Mercruiser 65–225 HP (Replaces 47-89984T5)

Water Pump Impeller Kit – Fits Mercury/Mercruiser 65–225 HP (Replaces 47-89984T5)

This water pump impeller kit is designed for a wide range of Mercury/Mercruiser and Force/Chrysler outboard engines. It fits most 65–225 HP 2-stroke Mercury/Mercruiser models from the 1960s to the 1990s, as well as Alpha One, MR, and pre-Alpha sterndrive units (serial numbers 2495186–0D469858). It is also compatible with 65–225 HP Force/Chrysler outboards that use short-vane impellers.

This kit serves as a direct replacement for multiple OEM and aftermarket part numbers, including Mercury 47-89984T5, 47-89984T4, 47-89984T6, and 47-89984Q5, as well as Sierra 18-3517, GLM 12120, Mallory 9-48307, and Sierra 18-3017.

• Installation: Direct OEM replacement designed for a precise fit.
• Core Component: Features a durable 6-blade neoprene rubber impeller with a brass hub.
• Complete Kit: Includes the impeller, face plate, gaskets, drive key, seals, and O-rings for a comprehensive service.

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM and aftermarket brands.

Compatible Engine Models

Confirm your engine model/year in the table below. For Mercury owners, here’s a guide to help you identify your engine’s serial/model: Mercury Serial Number Guide. You can also review exploded diagrams to verify part numbers: Mercury Parts Diagrams & Catalog.

Technical Specifications

Package Contents

• 1 x Water Pump Impeller (Replaces 47-89984, 47-30221, 47-65960, 47-85460)
• 1 x Face Plate with Gaskets
• 1 x Drive Key or Pin (Replaces 28-56654)
• 1 x Water Tube Guide Sleeve
• Multiple "O" Rings (exact quantity may vary by kit)
• 2 x Gearlube Fill & Vent Screw Seals

Installation Guide

1. Disconnect the negative battery cable to prevent accidental starting.
2. Place a drain pan under the lower unit and remove the gearlube drain/vent screws to empty the gear oil.
3. Remove the bolts that attach the lower unit (gearcase) to the engine's upper housing.
4. Carefully separate the lower unit from the engine. You may need to disconnect the speedometer tube if equipped.
5. Locate the water pump assembly on top of the gearcase and remove the bolts securing its housing.
6. Lift the pump housing and slide the old impeller off the drive shaft. Take note of the rotational direction of the vanes.
7. Wipe the housing interior and face plate clean. Inspect for scoring, warping, or corrosion and replace if damaged.
8. Install the new drive key, gaskets, and seals from the kit onto the drive shaft and base plate.
9. Slide the new impeller onto the drive shaft, turning the shaft clockwise to bend the vanes into the correct orientation.
10. Reinstall the water pump housing and tighten the bolts to the manufacturer's specified torque.
11. Reattach the lower unit to the engine and refill the gearcase with fresh marine gear lubricant.
12. Reconnect the battery, start the engine in a water supply, and confirm a strong, steady stream from the tell-tale outlet.

Troubleshooting & FAQ

How do I confirm this impeller kit fits my Mercury engine?

This kit fits a wide range of Mercury/Mercruiser outboards (65–225 HP, '60s–'90s) and Alpha One/MR sterndrives (serial # 2495186–0D469858). The best method is to check your model, HP, and serial number against the detailed compatibility tables on this page. You can also cross-reference your existing part number with those listed, such as Mercury 47-89984T5.

What are the signs that my water pump impeller needs to be replaced?

Common signs of a failing impeller include a weak or non-existent water stream from the "tell-tale" outlet, the engine overheating at idle or low speeds, or a high-temperature alarm sounding. Visually, a worn impeller will have cracked, brittle, or permanently bent vanes.

How often should I replace the water pump impeller?

As a preventative maintenance item, it is generally recommended to inspect the impeller annually and replace it every 1-2 years or every 100-200 hours of use, depending on operating conditions. More frequent replacement may be needed if you operate in sandy, silty, or saltwater environments.

OEM vs. Aftermarket?

This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

How fast do you ship and how much does it cost?

We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

What is your warranty and return policy?

This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

Important Notes

• Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
• This product is an aftermarket replacement part and is not an OEM component.
• Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

• Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
• Fast Global Shipping: Free delivery worldwide in 5–15 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.