Water Pump Base – Fits Mercury/Mariner 30-60 HP & Force 70-75 HP (Replaces 46-812966A7)

Water Pump Base – Fits Mercury/Mariner 30-60 HP & Force 70-75 HP (Replaces 46-812966A7)

This water pump base is a direct replacement for various Mercury, Mariner, and Force outboard engines. It is designed for 3 & 4 cylinder models, both 2-Stroke and 4-Stroke, from 1991 and newer, covering a horsepower range of 30-75 HP depending on the brand.

This component directly replaces OEM part numbers, including Mercury 46-812966A7, 46-812966A9, and 46-81266A3, as well as aftermarket equivalents from Sierra, GLM, and Mallory.

• Engineered for a direct OEM replacement fit.
• Constructed with a durable Stainless Steel housing.
• Manufactured to meet or exceed OEM specifications for reliable performance.

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.

Mercury/Mariner

Force

Technical Specifications

Package Contents

1 x Water Pump Base (46-812966A7)

Installation Guide

1. Disconnect Power: Start by disconnecting the battery terminals to prevent any electrical accidents.
2. Access Lower Unit: Remove the lower unit (gearcase) from the outboard motor. This typically involves removing several bolts connecting it to the midsection.
3. Remove Pump Housing: Unbolt and carefully lift the water pump housing to expose the impeller and the pump base.
4. Remove Old Base: Lift the old water pump base plate off the driveshaft and gearcase. Take note of any seals or gaskets underneath.
5. Clean Surfaces: Thoroughly clean the mounting surface on the gearcase where the new base will sit. Ensure it is free of old gasket material and corrosion.
6. Install New Base: Place the new water pump base into position, ensuring it is properly aligned with any guide pins or bolt holes.
7. Reassemble Pump: Install a new impeller, key, and gaskets. Re-attach the water pump housing and torque the bolts to the manufacturer's specification.
8. Re-attach Lower Unit: Slide the lower unit back into place, ensuring the driveshaft and water tube align correctly. Secure it with the mounting bolts.
9. Test Operation: Reconnect the battery. Start the engine using a water source (flushing muffs or in water) and check the tell-tale outlet for a strong, steady stream of water.

Troubleshooting & FAQ

Q: How can I confirm this base fits my specific engine?

A: Check your engine's model, year, and serial number against our compatibility tables. For Mercury models, you can use the provided serial number guide to verify your details. This base replaces OEM part number 46-812966A7 and others listed in the cross-reference table.

Q: What are the signs my water pump base needs replacement?

A: Common signs include engine overheating, a weak or inconsistent water stream from the tell-tale outlet, or visible cracks and corrosion on the existing base during a water pump service.

Q: How often should the water pump assembly, including the base, be inspected?

A: It is recommended to inspect the entire water pump assembly, including the impeller, housing, and base, every 100 hours of operation or at least once a year, whichever comes first. Replace components that show wear or damage.

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.