Mercury – Water Pump Impeller | Cooling System Component | Marine-Grade Elastomer | 42038K02

Overview

Keeping your engine cool is one of the simplest ways to keep it alive. The Mercury Marine 42038K02 Impeller does that job perfectly. Built for Mercury and Mariner 6–15 horsepower outboards, it pulls water through the system and keeps temperatures steady from idle to wide-open throttle. The flexible rubber blades bend easily under pressure and spring back into shape, keeping water moving no matter how hard the engine is working. It’s a small part that carries a big load — steady cooling, dependable performance, and fewer worries every time you fire up your motor.

Key Features

• Purpose: Moves water through your engine’s cooling system to prevent overheating.
• Material: Made from marine-grade flexible elastomer designed to last through heat, wear, and vibration.
• Performance: Maintains strong, even water flow across a wide temperature range.
• Design: Precision-fit to Mercury OEM specs for smooth rotation and balanced flow.
• Durability: Resists cracking, swelling, and fatigue, even in rough or hot running conditions.

Engine & Boat Compatibility

• Mercury and Mariner 6–15HP TwoStroke outboards.
• 8–9.9HP FourStroke (2004 & earlier) and 15HP FourStroke (2008 & earlier).
• Great for small fishing rigs, inflatables, aluminum skiffs, and portable outboards.
• Performs reliably in both saltwater and freshwater environments.

Performance & Real-World Benefits

A strong impeller is the heart of your cooling system. The 42038K02 impeller ensures constant water flow to keep your outboard running at the right temperature. Its flexible blades hug the housing tightly, pushing water efficiently even at low speeds.

This simple part prevents costly overheating and helps your motor maintain consistent performance. When replaced regularly, it extends the life of your water pump, impeller housing, and overall cooling system. Reliable, quiet, and durable — it’s the kind of part you install and forget because it just works.

Why Buy OEM

Mercury’s 42038K02 impeller is a genuine OEM component, built exactly for the engines it serves. Aftermarket impellers might look the same, but even small differences in shape or stiffness can cause poor flow or faster wear.

Mercury tests every impeller design for pressure, temperature, and durability in real boating conditions. You get the right fit, the right flexibility, and a part that will last season after season. When you go OEM, you’re not guessing — you’re guaranteeing your cooling system works the way it should.

FAQ

Q1: What engines does this fit?
It fits Mercury and Mariner 6–15HP TwoStroke outboards, plus 8–9.9HP FourStroke (2004 & earlier) and 15HP FourStroke (2008 & earlier).

Q2: What’s it made from?
It’s crafted from marine-grade elastomer that flexes easily and resists heat and wear.

Q3: How often should I replace it?
Inspect yearly and replace every two seasons or 200 hours, depending on use and water quality.

Q4: Is it safe for saltwater?
Yes — it’s designed to perform in both fresh and saltwater conditions.

Q5: Why OEM instead of aftermarket?
OEM impellers ensure perfect fit, reliable cooling pressure, and long life — things generic versions often miss.