QUICKMARINER outboard water pump impeller rebuild kit Mercury 30-70 HP complete parts for cooling restoration

This kit supplies the parts you'll need to replace a worn impeller and related components on many Mercury/Mariner outboard lower units. It includes the impeller, wear plate, housing components, gaskets and small hardware so you can return the water pump to reliable operation without sourcing multiple parts separately. Note: this service kit is intended to be paired with the separate 26-38452 / 26-38453 water pump housing seal kit for a full seal replacement when required.

Which engines and part numbers is this compatible with?

The QUICKMARINER 77177A3 kit fits a range of Mercury/Mariner 30 JET and 35–70 HP lower unit gearcases. It is designed to match OEM cross-references and common aftermarket equivalents, making it suitable for many routine rebuilds.

• Compatible Mercury/Mariner references: 46-73640A2, 46-77516A3, 46-77177A3.
• Replaces Sierra: 18-3322, 18-3323, 18-3324.
• Replaces GLM and Mallory aftermarket numbers listed in the product features.

What parts are included and why they matter?

The kit arrives as a ready-to-use service package so you can complete the impeller repair in one session. It covers all the wear items in the water pump assembly that commonly fail with age or debris exposure.

• Impeller and wear plate to restore impeller-to-housing clearance and pump efficiency.
• Housing, base, and gaskets to reseal the assembly and prevent leaks.
• Key, O-ring, drain screw gasket and rubber washer for proper alignment and sealing.

How do I know when to install this kit?

Install this kit when you observe reduced cooling flow, overheating, or after the engine has run with cavitation or debris ingestion. Routine preventive replacement every few seasons or at the first sign of impeller blade cracking, missing fins, or rubber hardening will avoid on-water breakdowns.

• Replace if impeller blades are torn, compressed, or brittle.
• Service when cooling passages show decreased flow or inconsistent temperature.
• Use as a scheduled maintenance spare before long trips or racing seasons.

Is installation difficult and what should I prepare?

Installation is straightforward for someone comfortable with lower-unit service procedures, basic hand tools, and following torque specs. If you’re not experienced with lower-unit removal or internal seals, have the 26-38452 / 26-38453 housing seal kit on hand or consult a technician to ensure a complete repair.

• Prepare a clean work area, appropriate hand tools, and a service manual for torque and sequence.
• Inspect the driveshaft, bearings, and cooling passages while the unit is open.
• Replace the housing seal kit when seals show wear or during multi-year rebuilds.

This QUICKMARINER 77177A3 kit is for boat owners, mechanics, and marinas that maintain Mercury/Mariner 30–70 HP outboards and prefer an all-in-one aftermarket service pack. It’s ideal as a preventive spare to carry on longer trips, a cost-effective rebuild option for routine maintenance, or a parts consolidation solution for shops that want compatible replacements to match OEM cross-references. If you need guaranteed OEM numbers or a full lower-unit overhaul, pair this kit with the recommended water pump housing seal kit or request professional installation.