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Piston Ring Set – Fits Yamaha F9.9/F15 4-Stroke Outboard Engines (Replaces 66N-11603-00-00)

Sale price $37.50 Regular price $60.00
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Worry-free returns

You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).

You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).

If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.

Delivery and Shipping

Free standard shipping on all orders under 1 KG

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 standard size Piston Ring Set – Fits Yamaha F9.9/F15 4-Stroke Outboard Engines is designed for Yamaha and Parsun 4-stroke outboards from 9.9 to 15 HP (model years 1998–2007). It provides a reliable OEM-quality solution for single-cylinder engine rebuilds, ensuring proper compression and oil control.

This set is a direct replacement for Yamaha part numbers 66N-11603-00-00, 66M-11603-00-00, and aftermarket equivalent Parsun F15-07020002.

  • Engineered for standard bore size (not for oversized pistons).
  • Installation is identical to standard OEM replacement procedures.
  • Includes a complete ring set for a single cylinder.

Part Number Matrix

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

Brand Part Number
Yamaha 66N-11603-00-00
Yamaha 66M-11603-00-00
Parsun F15-07020002

Engine & Model Compatibility

Confirm your engine model and year in the tables below to ensure correct fitment.

This part is compatible with a range of Yamaha 4-stroke outboard models from 9.9 HP to 15 HP, including high-thrust variants.

Brand Model Rated HP Stroke Years OEM Part No. Notes
Yamaha F9.9C/CE/CMH/CWH/D 9.9 4-Stroke 1998–2008 66N-11603-00-00
Yamaha F13.5AMH/AEH/AEP 13.5 4-Stroke 2000–2007 66N-11603-00-00
Yamaha F15A/PR/PLR/AEP/ELH/MH/AE/AM 15 4-Stroke 2000–2007 66N-11603-00-00
Yamaha F15ESHD 15 4-Stroke 2005 66N-11603-00-00
Yamaha F15MSHD 15 4-Stroke 2005 66N-11603-00-00
Yamaha F15ELHD 15 4-Stroke 2005 66N-11603-00-00
Yamaha F15MLH 15 4-Stroke 2004–2005 66N-11603-00-00
Yamaha F15MLHD 15 4-Stroke 2005 66N-11603-00-00
Yamaha F15PLRK 15 4-Stroke 2004–2006 66N-11603-00-00
Yamaha F15PLR 15 4-Stroke 2004–2006 66N-11603-00-00
Yamaha F9.9ELR2D 9.9 4-Stroke 2005 66N-11603-00-00
Yamaha F9.9MSH2D 9.9 4-Stroke 2005 66N-11603-00-00
Yamaha F9.9MSH2 9.9 4-Stroke 2004–2006 66N-11603-00-00
Yamaha F9.9ELR2K 9.9 4-Stroke 2004–2006 66N-11603-00-00
Yamaha F9.9MLH2K 9.9 4-Stroke 2004–2006 66N-11603-00-00
Yamaha F9.9MLH2D 9.9 4-Stroke 2005 66N-11603-00-00
Yamaha T9.9ELH2 9.9 4-Stroke 2004–2006 66N-11603-00-00 High thrust model
Yamaha T9.9ELR2K 9.9 4-Stroke 2004–2006 66N-11603-00-00 High thrust model
Yamaha T9.9ELH2K 9.9 4-Stroke 2004–2006 66N-11603-00-00 High thrust model
Yamaha T9.9ELH2D 9.9 4-Stroke 2005 66N-11603-00-00 High thrust model
Yamaha T9.9EXH2D 9.9 4-Stroke 2005 66N-11603-00-00 High thrust model
Yamaha T9.9EXH2K 9.9 4-Stroke 2004–2006 66N-11603-00-00 High thrust model
Yamaha T9.9ELR2 9.9 4-Stroke 2004–2006 66N-11603-00-00 High thrust model

This part is a direct cross-reference for several Parsun 4-stroke outboard models.

Brand Model Rated HP Stroke Years OEM Part No.
Parsun F9.9 9.9 4-Stroke 2004–2006 F15-07020002
Parsun F13.5 13.5 4-Stroke 2003–2006 F15-07020002
Parsun F15 15 4-Stroke 2003–2007 F15-07020002

Technical Specs

Product Type
Piston Ring Set
Installation
Standard OEM replacement
Dimensions (L x W x H)
11.0 x 10.5 x 0.4
Material
Steel
Application
Single cylinder
Ring Set Type
Complete set
Bore Size
Standard (not for oversized pistons)
OEM Interchange
66N-11603-00-00, 66M-11603-00-00
Aftermarket Interchange
Parsun F15-07020002

What’s in the Box

  • 1 x Piston Ring Set (replaces 66N-11603-00-00)

Installation Notes

  1. Always consult your engine’s official service manual for detailed instructions and safety precautions.
  2. Disconnect the battery and spark plug wires before beginning work.
  3. Carefully remove the cylinder head and piston assembly as per the manual's procedure.
  4. Use a ring expander tool to safely remove the old piston rings.
  5. Thoroughly clean the piston's ring grooves, removing all carbon deposits and oil residue.
  6. Install the new rings in the correct order and orientation, ensuring the ring gaps are staggered according to the manual.
  7. Generously lubricate the piston, new rings, and cylinder wall with fresh engine oil before reassembly.
  8. Reassemble all components, ensuring all bolts are torqued to the manufacturer's specified values.

Troubleshooting & FAQ

How do I know if this piston ring set will fit my engine?

This set is specifically for certain Yamaha and Parsun 4-stroke models from 9.9 HP to 15 HP, generally manufactured between 1998 and 2007. To guarantee fitment, please verify your engine's exact model and year against our compatibility tables before purchasing.

Is this for a standard or oversized piston?

This is a standard size (STD) ring set intended for a standard, non-modified cylinder bore. It is not suitable for oversized pistons or cylinders that have been bored out.

What are the common signs of failing piston rings?

Typical symptoms of worn piston rings include excessive blue or white smoke from the exhaust, unusually high oil consumption, loss of engine compression (leading to poor performance), and blow-by gases escaping from the crankcase.

My engine is a T9.9 "High Thrust" model. Will this fit?

Yes, this set is confirmed to be compatible with several Yamaha T9.9 High Thrust models manufactured between 2004 and 2006. Please see the detailed Yamaha compatibility chart above to confirm your specific model number.

The part number on my old part is 66M-11603-00-00. Is this correct?

Yes, this part directly replaces and interchanges with both Yamaha part numbers 66N-11603-00-00 and its predecessor, 66M-11603-00-00.

OEM vs. Aftermarket?

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

Shipping speed & cost

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

Warranty & returns

This product is covered by a 1-year warranty against manufacturing defects under normal marine use. If issues arise, contact our support team with your order details. Returns are accepted within our standard window for unused items in their original condition. Please see our policy page or reach out for instructions.

Safety & Important Info

  • Verify images and specifications against your original part before ordering. If any detail differs—even if your model appears on our compatibility list—do not purchase.
  • This is an aftermarket replacement component, not an Original Equipment Manufacturer (OEM) part.
  • Professional installation is strongly recommended for safety, proper function, and to prevent engine damage.

About Sea Sierra

  • Pro-Grade Standards — We supply marine parts engineered to strict OEM-level tolerances and rigorously tested for real-world conditions.
  • Fast Global Fulfillment — We offer free standard delivery to most regions worldwide, with typical transit times of 5–15 days.
  • Manufacturer-Direct Value — By working directly with our manufacturing partners, we provide fair pricing without ever compromising on materials or quality control.

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