676-44315-00 Water Pump Impeller Gasket for Yamaha OMC C40 235 240 | JLM Marine

Water Pump Impeller Gasket – Fits Yamaha 2-Stroke 40 HP & OMC 235/240 Stern Drive

This water pump impeller gasket is engineered to fit Yamaha 2-stroke 40 HP C40 outboard motors (1990–1997) and OMC Cobra stern drive models 235 (1971, 1975–1977) and 240 (1978). It provides a reliable seal for your water pump housing, ensuring proper cooling system performance and preventing leaks.

This gasket directly replaces OEM part numbers 676-44315-00, 676-44315-A0, and 676-44315-A1 across multiple Yamaha and OMC applications, offering broad compatibility for your maintenance and repair needs.

• Direct replacement for Yamaha and OMC water pump assemblies
• Precision-cut design for secure sealing and easy installation
• Essential component for water pump service and overhaul

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM brands.

Compatible Engine Models

Confirm your engine model/year in the table below. For Yamaha owners, here's a guide to help you identify your engine's serial/model: Yamaha Serial Number Guide. You can also review exploded diagrams to verify part numbers: Yamaha Parts Diagrams & Catalog.

Technical Specifications

Package Contents

This kit includes the following component:

• 1 × Water Pump Impeller Gasket (676-44315-00)

Installation Guide

1. Disconnect the battery and flush the cooling system before beginning work. Ensure the engine is completely cool.
2. Remove the lower unit from the outboard or stern drive according to your service manual. Locate the water pump housing assembly.
3. Disassemble the water pump housing and remove the old impeller gasket. Clean all mating surfaces thoroughly to remove debris, old gasket material, and residue.
4. Inspect the water pump housing and impeller for wear, cracks, or damage. Replace worn components as needed.
5. Position the new gasket (676-44315-00) onto the water pump housing, aligning all mounting holes and ports. Ensure proper orientation.
6. Reinstall the impeller and upper housing components per your service manual specifications. Torque all fasteners to manufacturer recommendations.
7. Reassemble the lower unit and reattach it to the motor. Double-check all connections and fasteners.
8. Reconnect the battery and test the cooling system by running the engine in a test tank or on muffs. Verify proper water flow and check for leaks around the gasket.

Troubleshooting & FAQ

Q: How do I confirm this gasket fits my specific engine?
A: Cross-reference your engine model and year with the compatibility table above. Verify your current gasket matches part number 676-44315-00, 676-44315-A0, or 676-44315-A1 to ensure proper fit.

Q: How often should I replace the water pump impeller gasket?
A: Replace the gasket every time you service or rebuild your water pump assembly. Most manufacturers recommend water pump service every 2–3 years or 200–300 hours of operation, whichever comes first.

Q: What are the signs that my water pump gasket has failed?
A: Common symptoms include overheating, reduced water flow from the tell-tale, visible coolant leaks around the lower unit, or steam from the engine. If you notice any of these signs, inspect and replace the gasket immediately.

Q: Can I reuse the old gasket during water pump service?
A: No, gaskets are designed for single use and compress to form a seal. Reusing an old gasket can result in leaks, poor sealing, and potential engine damage from overheating.

Q: Is this an OEM gasket or an aftermarket replacement?
A: This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

Q: How fast do you ship and how much does it cost?
A: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

Q: What is your warranty and return policy?
A: This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

Important Notes

• Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
• This product is an aftermarket replacement part and is not an OEM component.
• Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

• Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
• Fast Global Shipping: Free delivery worldwide in 5–15 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.