Piston Kit (STD) – Fits Yamaha 115HP-200HP V4/V6 Outboards (Replaces 6G5-11631-00-K)
Piston Kit (STD) – Fits Yamaha 115HP-200HP V4/V6 Outboards (Replaces 6G5-11631-00-K) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
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
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Product Details
This aftermarket Piston Kit (STD) – Fits Yamaha 115HP-200HP V4/V6 Outboards is designed for a range of Yamaha 2-Stroke 115HP, 140HP, 150HP, 175HP, and 200HP V4 & V6 outboard motors manufactured between 1984 and 1987. It serves as a reliable replacement for the original starboard-side piston assembly.
This kit is a direct replacement for Yamaha OEM part numbers 6G5-11631-00-K and 6G5-11631-00-93.
- Engineered for the starboard position in V4/V6 engine blocks.
- Manufactured from a high-grade aluminum alloy for durability.
- Includes the piston, rings, clips, and wrist pin for a complete installation.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Yamaha | 6G5-11631-00-K |
| Yamaha | 6G5-11631-00-93 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Yamaha | ETL | 115 | 2-Stroke | 1984–1987 | 6G5-11631-00 | Starboard |
| Yamaha | ETL-JD | 115 | 2-Stroke | 1987 | 6G5-11631-00 | Starboard |
| Yamaha | ETX | 115 | 2-Stroke | 1984–1987 | 6G5-11631-00 | Starboard |
| Yamaha | ETL | 150 | 2-Stroke | 1984–1987 | 6G5-11631-00 | Starboard |
| Yamaha | ETX | 150 | 2-Stroke | 1984–1987 | 6G5-11631-00 | Starboard |
| Yamaha | L-ETX | 150 | 2-Stroke | 1986–1987 | 6G5-11631-00 | Starboard |
| Yamaha | Pro-V | 150 | 2-Stroke | 1986–1987 | 6G5-11631-00 | Starboard |
| Yamaha | ETL | 175 | 2-Stroke | 1984–1987 | 6G5-11631-00 | Starboard |
| Yamaha | ETX | 175 | 2-Stroke | 1984–1987 | 6G5-11631-00 | Starboard |
| Yamaha | ETL | 200 | 2-Stroke | 1984–1987 | 6G5-11631-00 | Starboard |
| Yamaha | ETL-JD | 200 | 2-Stroke | 1987 | 6G5-11631-00 | Starboard |
| Yamaha | ETX | 200 | 2-Stroke | 1984–1987 | 6G5-11631-00 | Starboard |
| Yamaha | L-ETX | 200 | 2-Stroke | 1986–1987 | 6G5-11631-00 | Starboard |
Technical Specs
- Product Type
- Piston Kit
- Material
- High-grade aluminum alloy
- Piston Diameter
- 90mm
- Piston Height
- 3.75 in
- Wrist Pin Diameter
- 21.5mm
- Engine Type
- 2-Stroke
- Position
- Starboard
- Weight
- 0.68 kg (1.5 lbs)
- Dimensions
- 3.75" L x 4.0" W x 3.75" H
- Warranty
- 1 year (aftermarket)
What’s in the Box
- 1 x Piston
- 1 x Set of Piston Rings
- 2 x Piston Clips
- 1 x Wrist Pin
Installation Notes
- Disconnect the battery and ensure the engine is cool. Drain the engine coolant and oil.
- Remove the cylinder head and any interfering components to access the old piston.
- Carefully remove the old piston, wrist pin, and clips. Clean the cylinder wall and connecting rod thoroughly.
- Install one wrist pin clip into the new piston. Lubricate the new wrist pin and slide it through the piston and connecting rod.
- Secure the second wrist pin clip. Ensure both clips are fully seated in their grooves.
- Install the new piston rings onto the piston according to the manufacturer's guide.
- Lubricate the piston, rings, and cylinder wall with 2-stroke engine oil.
- Using a ring compressor, carefully slide the piston assembly into the cylinder.
- Reassemble the cylinder head and all other components, torquing bolts to factory specifications.
- Refill engine fluids, reconnect the battery, and check for leaks before starting.
Troubleshooting & FAQ
How do I know if I need to replace my piston?
Common signs of a failing piston include loss of compression, excessive smoke from the exhaust, a knocking sound from the engine, or metal shavings found in the engine oil. Performing a compression test is the most definitive way to diagnose piston or ring issues.
Is this piston for the port or starboard side?
This specific kit (replaces 6G5-11631-00-K) is designed for the starboard (STB) side of the engine. Please ensure you are ordering the correct piston for the cylinder you are servicing.
What is the break-in procedure for a new piston?
For a new piston, it's recommended to follow a gentle break-in period. Avoid running the engine at full throttle for extended periods for the first 10-15 hours of operation. Vary the RPMs and avoid sustained high or low speeds to allow the new rings to seat properly against the cylinder wall.
Can I reuse my old piston rings or wrist pin?
No. This kit includes all necessary new components (piston, rings, wrist pin, and clips). You should never reuse old rings, clips, or pins, as they are wear items and critical for proper engine function and longevity.
What's the difference between OEM and this aftermarket piston?
This listing is an aftermarket replacement (not OEM). It's built to OEM-level specifications with comparable high-grade aluminum alloys. Our parts are manufactured in an ISO 9002 certified facility and are batch-inspected for quality and consistency to ensure reliable performance.
How fast do you ship and what are the costs?
We ship worldwide quickly—typical transit is 5–15 days. Standard shipping is free to most locations, with expedited options available at checkout if applicable to your region.
What is the warranty and return policy?
This product is covered by a 1-year warranty against manufacturing defects under normal use. If you encounter any issues, please contact our support team with your order details. Returns are accepted within our standard window for unused items in their 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.
Payment & Security
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