SIERRA 18-3087 Water Pump Impeller Inboard Outboard Inboard/outboard 47-59362

( Brand: Sierra ), ( Manufacturer Part Number: 18-3087 ), ( Bundle Description: Sierra Water Pump Impeller Replaces Mercruiser Inboard/outboard 4 ), ( Compatible Product: Other Compatible Product ), ( Custom Bundle: No ), ( Type: Outboard ), ( Size: Medium )

Review SIERRA Water Pump Impeller Replaces Inboard/outboard fits MERCRUISER

The **Mercruiser Sierra 18-3087 Water Pump Impeller** (part number **47-59362**) is a precision-engineered marine component designed to deliver reliable hydraulic performance for inboard and outboard propulsion systems manufactured by Mercruiser, particularly those found in mid-sized to larger recreational and performance boats. Crafted from high-grade, corrosion-resistant materials, this impeller is built to withstand the demanding conditions of saltwater environments while maintaining optimal efficiency in fluid circulation. Its unique design features a **three-blade configuration**, which ensures smooth water flow and minimizes turbulence, thereby reducing wear on the water pump and engine components over time. The impeller s **balanced construction** helps mitigate vibration, contributing to quieter operation and prolonged longevity of the associated cooling system. Whether installed in a **Mercruiser Alpha, Beta, or Bravo series engine**, this impeller is engineered to handle the rigorous demands of marine applications, including high-speed cruising, towing, and heavy-duty recreational use. Its compatibility with **Mercruiser s 47-series water pump assemblies** makes it an essential replacement part for maintaining peak cooling efficiency, preventing overheating, and ensuring the overall reliability of your propulsion system. Built to meet OEM specifications, this impeller is a direct-fit solution that restores factory performance, making it an ideal choice for boat owners seeking durability, performance, and long-term dependability in their marine engine systems.

### **Pros and Cons of buying a Sierra 18-3087 Water Pump Impeller (Mercruiser Inboard/Outboard 47-59362)**

1. **Compatibility** This impeller is specifically designed for Mercruiser inboard/outboard engines from the 47-59362 series, ensuring a proper fit without modification. This reduces the risk of improper installation, which can lead to leaks or damage.

2. **Performance Reliability** A high-quality impeller like the Sierra brand is engineered to maintain optimal water flow, preventing overheating and ensuring efficient cooling for the engine. Proper water circulation is critical for long-term engine health.

3. **Durability** Sierra is a reputable manufacturer known for producing durable marine components. The impeller is likely made from corrosion-resistant materials, which is essential for saltwater and freshwater environments.

4. **Easy Replacement** Since this is an OEM or high-quality aftermarket part, replacing it is straightforward if the original fails. Many mechanics and boat owners report that aftermarket impellers from trusted brands fit seamlessly.

5. **Prevents Engine Damage** A failing water pump impeller can lead to catastrophic engine failure due to overheating. Replacing it proactively can save thousands in repair costs.

6. **Warranty Coverage** Some aftermarket brands, including Sierra, offer warranties on their products, providing peace of mind against defects.

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1. **Cost** While not excessively expensive, aftermarket impellers may be slightly more costly than generic or lower-quality alternatives. However, the price difference is often justified by performance and longevity.

2. **Potential Mix-Ups with OEM Parts** If the original impeller was a specific model (e.g., a different material or design), there is a small risk of confusion, though the 47-59362 designation minimizes this.

3. **Installation Requires Basic Mechanical Skill** While not overly complex, replacing an impeller requires draining the water, removing the old impeller, and ensuring the new one is properly seated. Those without mechanical experience may need professional assistance.

4. **Availability** Depending on location, this part may not be stocked at every marine supply store. Online retailers (e.g., Amazon, West Marine, or specialty marine parts suppliers) are more likely to carry it.

5. **Potential for Counterfeit Parts** As with any aftermarket component, there is a risk of purchasing a knockoff. Buying from a trusted dealer or directly from the manufacturer reduces this risk.

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### **Conclusion**

The **Sierra 18-3087 water pump impeller (Mercruiser 47-59362)** is a solid choice for boat owners needing a reliable replacement. Its **compatibility, durability, and performance benefits** far outweigh the minor drawbacks, such as cost and installation requirements. The most significant advantage is **preventing engine damage**, which is far more costly than the part itself.

If your engine is showing signs of poor cooling (e.g., overheating, reduced performance, or unusual noises from the water pump), replacing the impeller is a **proactive and cost-effective solution**. For those comfortable with basic DIY repairs, this is an excellent aftermarket option. If unsure, consulting a marine mechanic ensures proper installation.

### **Recommendation**

- You need a **direct replacement** for your Mercruiser 47-59362 engine.

- You prioritize **quality, longevity, and performance** over the lowest price.

- You are willing to **install it yourself** or have a mechanic do it.

**Avoid generic or unknown brands** unless you are certain of their quality, as a failed impeller can lead to **expensive engine repairs**. Always verify the part number and source it from a **reputable dealer** to ensure authenticity.

Details:

Sierra 18-7891 Oil Drain Kit -1/2. Westinghouse 4LB25AH4BC Battery OPE, with 2.5 Ah, Blue. This platform is now integrated and seamless. Sierra Carburetor Repair Kit Yamaha Outboard Motors 6L2-W0093-00-00 18-7739.

part #: 183087 prices

• $5.00-$40.00

specifications ignitionstartin:

• for models: Mercruiser
• brand: Sierra
• mpn: 18-3087
• bundle description: Sierra Water Pump Impeller Replaces Mercruiser Inboard/outboard 4
• compatible product: Other Compatible Product
• custom bundle: No
• type: Outboard
• size: Medium

offer ignitionstartin:

• sold: 0
• availability: In Stock
• options: Ship-to-home
• started: June 8, 2026

payments ignitionstartin:

• wallet: Paypal
• credit card: Mastercard
• other

general ignitionstartin:

• Boat Parts > Inboard Engines Components > Ignition Starting Systems
• condition: New

seller ignitionstartin:

• rating: 99.0%
• city: Wheeling, Illinois
• # reviews: 113218

shipping ignitionstartin:

• type: Fixed
• transit: 4-12 Days
• class: Economy
• cost: $0.00
• service: Economy

returns ignitionstartin:

• paid by: Seller
• time: 30 Days
• policy: Returns Accepted

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