663-W006A-00 Maintenance Kit for Yamaha 55HP BET | JLM Marine

Maintenance Kit for Yamaha 55HP BET – Complete Service Package (663-W006A-00)

This comprehensive maintenance kit is designed for Yamaha 55HP 2-Stroke BET models (1995-1997), providing all essential components for routine servicing in one convenient package. Whether you're performing seasonal maintenance or a complete tune-up, this kit ensures your engine runs smoothly and reliably.

Directly replaces OEM part number 663-W006A-00, offering a complete solution that includes gaskets, impeller, thermostat, fuel filter, fasteners, and gear oil pump—eliminating the need to source individual components separately.

• Includes 15 components covering water pump, fuel system, and cooling system maintenance
• Features genuine-specification impeller, thermostat, and fuel filter for optimal performance
• All necessary gaskets, fasteners, and hardware included for complete installation

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM and aftermarket 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 maintenance kit includes the following 15 components for complete engine servicing:

• 663-44315-A0 – Gasket × 1
• 663-44322-00 – Cup, Insert × 1
• 663-44323-00 – Plate, Wear × 1
• 663-44324-A0 – Gasket × 1
• 663-44366-00 – Grommet × 1
• 6H3-44352-00 – Impeller × 1
• 90280-03M03 – Key × 1
• 97095-08055 – Bolt × 2
• 97095-08045 – Bolt × 2
• 61N-24560-00 – Fuel Filter × 1
• 6F5-12411-30 – Thermostat × 1
• 663-12414 – Thermostat Gasket × 1
• 90430-08020 – Drain Gasket × 4
• 91490-30025 – Cotter Pin × 1
• 24OP149 – Gear Oil Pump × 1

Installation Guide

1. Disconnect the fuel line and remove the engine cowling to access internal components. Ensure the engine is cool and tilted properly for safe access.
2. Remove the water pump housing by loosening the mounting bolts with the appropriate socket. Set aside the old impeller, wear plate, and gaskets.
3. Clean the water pump cavity thoroughly, removing any debris or old gasket material. Inspect for corrosion or damage that may require additional service.
4. Install the new wear plate (663-44323-00) and insert cup (663-44322-00) into the housing. Apply a thin layer of marine grease to ease impeller installation.
5. Lubricate the new impeller (6H3-44352-00) with glycerin or soapy water, then carefully insert it into the housing with blades oriented correctly. Install the key (90280-03M03) into the drive shaft slot.
6. Position the new gaskets (663-44315-A0 and 663-44324-A0) onto the pump housing, ensuring proper alignment. Apply a small amount of sealant if recommended by service manual.
7. Reinstall the water pump housing and secure with the provided bolts (97095-08055 and 97095-08045), tightening in a criss-cross pattern to manufacturer torque specifications.
8. Replace the fuel filter (61N-24560-00) by disconnecting fuel lines and swapping the old filter with the new unit. Ensure hose clamps are secure to prevent leaks.
9. Remove the old thermostat and install the new thermostat (6F5-12411-30) with its gasket (663-12414) into the cooling system housing. Verify proper seating before tightening the cover.
10. Replace all drain gaskets (90430-08020) on oil drain plugs and install the cotter pin (91490-30025) as needed for lower unit assembly. Check that all fasteners are secure.
11. Use the gear oil pump (24OP149) to refill the lower unit with fresh gear oil per manufacturer recommendations. Monitor for proper level and absence of leaks.
12. Reconnect all fuel lines, reinstall the cowling, and run the engine to verify water pump flow and proper operating temperature. Check all service points for leaks before returning to service.

Troubleshooting & FAQ

Q: How do I confirm this maintenance kit fits my Yamaha engine?
A: This kit is designed specifically for Yamaha 55HP 2-Stroke BET models from 1995 to 1997. Verify your engine model designation (stamped on the mounting bracket or transom clamp) and cross-reference the OEM part number 663-W006A-00 with your service manual or parts diagram.

Q: How often should I perform maintenance using this kit?
A: Yamaha recommends annual maintenance or every 100 hours of operation, whichever comes first. If you operate in sandy, silty, or saltwater conditions, consider servicing more frequently—every 50 hours or mid-season—to prevent premature wear.

Q: What are the signs that my water pump impeller needs replacement?
A: Look for weak water flow from the tell-tale (pilot hole), engine overheating, steam from the cowling, or alarm activation. A damaged impeller may also cause erratic temperature readings or reduced performance under load.

Q: Can I reuse the old gaskets if they appear undamaged?
A: No, always install new gaskets included in this kit to ensure proper sealing and prevent leaks. Reusing old gaskets—even if they look intact—can lead to cooling system failures or water intrusion into the powerhead.

Q: Does this kit include everything I need for a complete service?
A: This kit covers water pump, fuel filter, thermostat, and lower unit drain gaskets, plus a gear oil pump for fluid changes. You will need to supply fresh gear oil, engine oil (if applicable), and basic hand tools separately.

Q: What's the difference between OEM and aftermarket maintenance kits?
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.