Water Pump Impeller Housing – Fits Mercury/Mariner 40-60 HP (Replaces 14334A3)

Water Pump Impeller Housing – Fits Mercury/Mariner 40-60 HP (Replaces 14334A3)

This water pump impeller housing is a direct replacement for Mercury and Mariner 40-60 HP outboard engines, covering a wide range of 2-stroke and 4-stroke models from 1991 to the present. Engineered to meet or exceed original equipment standards, it ensures reliable cooling system performance.

It serves as a direct replacement for Mercury part numbers 14334A3 and 812966A12, Quicksilver 14334A3, and Sierra 18-3578, providing a precise fit for straightforward installation.

• Installation Method: Direct OEM replacement
• Housing Material: High-strength cast metal alloy for durability and corrosion resistance.
• Manufacturing Standard: Produced in an ISO9002-certified facility to guarantee quality and consistency.

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

When purchased as housing-only part number 14334A3:

• 1 x Water Pump Impeller Housing (Replaces 14334A3)

When purchased as complete kit 46-812966A12:

• 1 x Impeller (47-19453T)
• 1 x Plate (19700A2)
• 1 x Housing (14334A3)
• 1 x Base (46-812966A7)
• 1 x Coupler/Guide Tube (859770/859770-1/893857)
• 2 x Washer (12-858234)
• 1 x Gasket Upper (27-822189)
• 1 x Gasket Lower (27-19701)
• 1 x Impeller Key
• 1 x O-Ring

Installation Guide

1. Disconnect the negative battery cable for safety.
2. Place a drain pan under the lower unit and remove the gear lube drain/vent screws to empty the oil.
3. Remove the bolts securing the lower unit (gearcase) to the outboard's upper leg section. Carefully lower and separate the unit.
4. Locate the water pump assembly on top of the gearcase. Remove the bolts holding the pump housing in place.
5. Slide the old housing off the driveshaft, being careful not to lose the impeller key. Remove the old impeller and wear plate.
6. Clean the mounting surface on the gearcase base thoroughly, removing any old gasket material or sealant.
7. Install the new lower gasket, wear plate, and impeller key. Slide the new impeller onto the driveshaft, rotating it in a clockwise direction.
8. Apply a light coat of marine grease or soap to the inside of the new housing.
9. Press the new housing down over the impeller while turning the driveshaft clockwise to seat the vanes correctly.
10. Install the new upper gasket and secure the housing with its bolts, tightening them to the manufacturer's specified torque.
11. Reinstall the lower unit, ensuring the driveshaft, shift shaft, and water tube align correctly.
12. Refill the gearcase with fresh lubricant, reinstall the battery cable, and test the engine's cooling stream in water.

Troubleshooting & FAQ

Q: How do I confirm this housing fits my specific engine?
A: The most reliable method is to find your engine's serial number, which is typically on a tag on the transom bracket. Cross-reference this number with the ranges listed in our "Compatible Engine Models" table. For Mercury owners, our linked serial number guide can help you locate and understand your model information.

Q: What is the difference between purchasing part 14334A3 versus the complete kit?
A: Part number 14334A3 on its own includes only the metal water pump housing. The complete kit, 46-812966A12, is a full rebuild kit that includes the housing plus the impeller, wear plate, gaskets, o-rings, and other hardware needed for a comprehensive service.

Q: My engine is a 60 HP Mercury Bigfoot from 1994. Will this part fit?
A: No. The compatibility data clearly notes this part will NOT fit standard (non-Bigfoot) 60 HP 2-stroke models from 1991-1995 or Bigfoot models from 1998-2005. Always check the "Notes" column for specific exclusions.

Q: How often should the water pump housing be replaced?
A: While the flexible rubber impeller should be replaced every 1-2 years (or every 100-200 hours), the housing itself has a longer lifespan. You should inspect the housing for signs of scoring, warping, or corrosion during every impeller change. Replace it if any damage that could compromise the impeller's seal is visible.

Q: OEM vs. Aftermarket?
A: 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.

Q: How fast do you ship and how much does it cost?
A: 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.

Q: What is your warranty and return policy?
A: 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.