UANOFCN Water Pump Impeller Repair Kit for Mercury 4-Stroke 30-60 HP EFI — 3.44 in Torpedo, Long-Tube Seal

This UANOFCN kit bundles the parts required to restore cooling performance on compatible Mercury 4-stroke outboard motors. It’s built for engines that require a long-tube seal and a torpedo (drive shaft) diameter of 3.44 in (87.38 mm). The set contains the impeller, housing, wear plates, gaskets, seals and small hardware so you can do a thorough pump service in one visit.

Which Mercury models and part numbers does this kit replace?

This kit matches common Mercury 4-stroke EFI outboards in the 30–60 HP range and cross-references several OEM and aftermarket numbers. Use the part numbers below to confirm compatibility with your engine parts list.

• Direct OEM cross-reference: 46-812966A12
• Also compatible with: 46-14334A2, 46-14334A1, 46-812966A6, 46-812966A5, 46-812966A4
• Aftermarket equivalent: Sierra 18-3690

How do I know this is the correct torpedo size and seal length for my engine?

Measure the torpedo (drive shaft sleeve) diameter before ordering; this kit is for the 3.44 in (87.38 mm) size. The included long-tube seal is intended specifically for 4-stroke lower units—2-stroke engines normally require a short-tube seal.

• Torpedo diameter required: 3.44 in / 87.38 mm
• Includes a long tube seal suitable for 4-stroke lower units
• Not suitable if your engine specification calls for a short-tube seal

What parts are included and what will I need to complete the repair?

The package contains all the primary components needed to rebuild the water pump assembly so you can replace worn parts and restore proper coolant flow. You may still need basic tools and marine-grade lubricant for installation and sealing surfaces.

• Water pump impeller and impeller key
• Pump housing, base, wear plate and lower wear plate gasket
• Upper gasket, tube seal, O-rings, plastic washer, metal seal and stainless washers

When should I replace the entire water pump assembly instead of just the impeller?

Replace the full kit when you find hardened or badly eroded impeller blades, corroded housings, or leaking seals. A complete repair kit reduces the chance of repeated failures and addresses both rotating and sealing surfaces at once.

• Replace when impeller rubber is brittle, torn or warped
• Replace if pump housing or wear plate is scored or corroded
• Replace if you detect coolant leaks around the tube seal or gaskets

Who is this for: Boaters, marine mechanics and DIY enthusiasts who own Mercury 4-stroke 30–60 HP EFI outboards needing a full water pump rebuild will benefit from this UANOFCN kit. It’s aimed at users who prefer to replace all relevant parts at once—impeller, seals, gaskets and hardware—especially when the torpedo diameter is 3.44 in and a long tube seal is specified for the lower unit. Verify your engine model and torpedo measurement before ordering to ensure a correct fit.