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FLASHSALE26

Water Pump Impeller – Fits Yamaha 2.5HP, 3HP Outboard Motors (Replaces 6L5-44352-00-00, 18-8911)

Regular price $13.00

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Orders are typically processed within 1–2 business days.


U.S. orders usually arrive within 6–15 days, depending on stock location and destination.


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If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This is a direct replacement Water Pump Impeller – Fits Yamaha 2.5HP, 3HP Outboard Motors (Replaces 6L5-44352-00-00). It is designed for a precise fit on Yamaha 2.5HP & 3HP 4-Stroke outboards from 2003–2022 and 3HP 2-Stroke outboards from 1988–2002, ensuring reliable cooling performance for your engine's water pump system.

This impeller directly interchanges with Yamaha 6L5-44352-00-00, Sierra 18-8911, Mallory Marine 9-45615, and CEF 500322 for a perfect fit and function.

  • Engineered for direct-fit installation.
  • Constructed from durable neoprene and hardened nylon for longevity.
  • Includes the necessary drive pin for a complete replacement.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand Part Number
Yamaha 6L5-44352-00-00
Sierra 18-8911
Mallory Marine 9-45615
CEF 500322

Engine & Model Compatibility

Confirm your engine model/year in the table below.

This part is designed exclusively for specific Yamaha outboard engines. Please verify your exact model and year before ordering.

Brand Model Rated HP Stroke Years OEM Part No. Notes
Yamaha F2.5A/F2.5 2.5 4-Stroke 2003–2022 6L5-44352-00-00
Yamaha F2.5LMHA 2.5 4-Stroke 2013–2015 6L5-44352-00-00
Yamaha F2.5LMHB 2.5 4-Stroke 2015–2022 6L5-44352-00-00
Yamaha F2.5MSH 2.5 4-Stroke 2005–2010 6L5-44352-00-00
Yamaha F2.5MSHB 2.5 4-Stroke 2003 6L5-44352-00-00
Yamaha F2.5MSHC 2.5 4-Stroke 2004 6L5-44352-00-00
Yamaha F2.5MSHD 2.5 4-Stroke 2005 6L5-44352-00-00
Yamaha F2.5SMHA 2.5 4-Stroke 2011–2015 6L5-44352-00-00
Yamaha F2.5SMHB 2.5 4-Stroke 2015–2022 6L5-44352-00-00
Yamaha 3MLHP 3 2-Stroke 1991 6L5-44352-00-00
Yamaha 3MLHQ 3 2-Stroke 1992 6L5-44352-00-00
Yamaha 3MLHR 3 2-Stroke 1993 6L5-44352-00-00
Yamaha 3MLHS 3 2-Stroke 1994 6L5-44352-00-00
Yamaha 3MLHT 3 2-Stroke 1995 6L5-44352-00-00
Yamaha 3MLHU 3 2-Stroke 1996 6L5-44352-00-00
Yamaha 3MLHV 3 2-Stroke 1997 6L5-44352-00-00
Yamaha 3MLHW 3 2-Stroke 1998 6L5-44352-00-00
Yamaha 3MLHX 3 2-Stroke 1999 6L5-44352-00-00
Yamaha 3MLHY 3 2-Stroke 2000 6L5-44352-00-00
Yamaha 3MSHP 3 2-Stroke 1991 6L5-44352-00-00
Yamaha 3MSHQ 3 2-Stroke 1992 6L5-44352-00-00
Yamaha 3MSHR 3 2-Stroke 1993 6L5-44352-00-00
Yamaha 3MSHS 3 2-Stroke 1994 6L5-44352-00-00
Yamaha 3MSHT 3 2-Stroke 1995 6L5-44352-00-00
Yamaha 3MSHU 3 2-Stroke 1996 6L5-44352-00-00
Yamaha 3MSHV 3 2-Stroke 1997 6L5-44352-00-00
Yamaha 3MSHW 3 2-Stroke 1998 6L5-44352-00-00
Yamaha 3MSHX 3 2-Stroke 1999 6L5-44352-00-00
Yamaha 3MSHY 3 2-Stroke 2000 6L5-44352-00-00
Yamaha 3MSHZ 3 2-Stroke 2001 6L5-44352-00-00
Yamaha 3MSHA 3 2-Stroke 2002 6L5-44352-00-00
Yamaha 3MSHKZ 3 2-Stroke 2001 6L5-44352-00-00
Yamaha 3LF 3 2-Stroke 1989 6L5-44352-00-00
Yamaha 3SF 3 2-Stroke 1989 6L5-44352-00-00
Yamaha 3LD 3 2-Stroke 1990 6L5-44352-00-00
Yamaha 3SD 3 2-Stroke 1990 6L5-44352-00-00
Yamaha 3LG 3 2-Stroke 1988 6L5-44352-00-00
Yamaha 3SG 3 2-Stroke 1988 6L5-44352-00-00

Technical Specs

Product Type
Water Pump Impeller
Installation
Direct Replacement
Material
Neoprene and Hardened Nylon
Number of Blades
6
Dimensions
Height: 14.5mm (0.57 in), Diameter: 36mm (1.42 in), Hub Shaft Diameter: 9.9mm (0.39 in)
Weight
10g (0.35 oz)
Color
Black
OEM Part Number
Yamaha 6L5-44352-00-00
Other Technical Attributes
Includes drive pin

What’s in the Box

  • 1 x Water Pump Impeller (6L5-44352-00-00)
  • 1 x Drive Pin

Installation Notes

  1. Disconnect the negative battery cable for safety.
  2. Remove the lower unit (gearcase) from the outboard motor.
  3. Locate and unbolt the water pump housing to access the impeller.
  4. Remove the old impeller, taking note of the blade direction, and remove the drive key.
  5. Clean the inside of the pump housing and inspect it for scoring or corrosion. Replace if damaged.
  6. Place the new drive key in the shaft slot.
  7. Slide the new impeller onto the driveshaft, turning the shaft clockwise to help fold the blades into the housing correctly.
  8. Re-install the water pump housing with a new gasket and torque bolts to manufacturer specifications.
  9. Re-attach the lower unit to the outboard motor.
  10. Test the cooling system by running the engine in water and ensuring a steady stream of water from the tell-tale port.

Troubleshooting & FAQ

How do I know if this impeller will fit my Yamaha outboard?

This impeller is designed for specific Yamaha models. Please check the comprehensive "Engine & Model Compatibility" table on this page. Verify your engine's model number, horsepower, and year range to ensure a correct match.

What are the signs of a failing water pump impeller?

Common symptoms include a weak or non-existent water stream from the "tell-tale" outlet, engine overheating alarms, or a noticeable decrease in engine performance. A physically brittle, cracked, or deformed impeller upon inspection also indicates it's time for replacement.

How often should I replace my impeller?

As a best practice, impellers should be inspected annually and replaced every 1-2 years or every 100-200 hours of operation, depending on usage conditions (freshwater vs. saltwater). This preventative maintenance can prevent unexpected engine overheating.

What is the difference between this impeller and the OEM part?

This is a high-quality aftermarket part designed to meet or exceed original equipment manufacturer (OEM) specifications for fit, form, and function. It offers comparable performance and material quality at a better value.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

  • Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
  • This is an aftermarket replacement, not an OEM component.
  • Professional installation is recommended for safety and performance.

About Sea Sierra

  • Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
  • Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
  • Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.

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