Upgrade Your Outboard with the Sierra 18-3316 Water Pump Kit

Keep your Mercury outboard running cool and efficient with the Sierra 18-3316 water pump kit, a direct replacement for Mercury Marine part 46-96148A 8. Designed for boaters who demand reliability on the water, this kit delivers OEM-level performance without the premium price tag. Whether you're prepping for a long fishing trip or routine maintenance, installing this water pump ensures optimal cooling to protect your engine from overheating.

Perfect Fit for Mercury 75-125 HP 4-Cylinder Engines

This water pump kit is engineered specifically for Mercury and Mariner 75-125 HP 4-cylinder 2-stroke outboards, covering popular models from the late 1990s through mid-2000s. It matches the exact specifications of the original MC#46-96148A 8 assembly, including the impeller, housing, wear plate, and all necessary seals and gaskets. Boaters report seamless bolt-on installation, saving hours compared to mismatched aftermarket parts.

• Compatible with gearcase lower units on select 75, 90, 115, and 125 HP models
• Restores factory water flow for peak engine temperatures
• Prevents cavitation and impeller spin-out during high-RPM operation

Built to Last with Premium Materials

Sierra stands out in the marine aftermarket by using bronze housing for corrosion resistance in saltwater environments and a high-durometer neoprene impeller that resists deformation under heat and pressure. Every kit undergoes rigorous testing to exceed industry standards, ensuring years of trouble-free service. Unlike generic rebuild kits, the 18-3316 includes everything needed for a complete refresh—no hunting for missing o-rings or gaskets.

Key Components Included

Easy DIY Installation Tips

Swapping out your water pump doesn't have to be a weekend project. Start by flushing the cooling system, then remove the lower gearcase bolts and inspect the driveshaft splines. Lubricate the new impeller with marine grease during install to ease startup. Most users complete the job in under two hours with basic tools—a must-have skill for any serious angler or weekend warrior.

1. Drain gear lube and separate lower unit
2. Remove old pump assembly carefully
3. Align new impeller and key precisely
4. Torque to spec and test flush before trailering

Pro tip: Replace the water pump every 2-3 years or 300 hours, especially if you notice reduced pee stream from the tell-tale.

Why Sierra Over OEM?

Sierra's reputation for quality control shines through in real-world use. Independent tests show their impellers outlast competitors by 20-30%, thanks to advanced molding techniques. Save on rebuilds while gaining peace of mind—thousands of satisfied boaters swear by Sierra for everything from bass boats to offshore rigs.

Frequently Asked Questions

Equip your Mercury outboard with proven reliability. The Sierra 18-3316 water pump kit keeps you on the water, not in the shop.