Piston Kit – Fits Yamaha Outboard 9.9/15HP 2-Stroke (Replaces 6E7-11631-00-97)

Product Details

This high-quality Piston Kit is designed for Yamaha 9.9/15HP 2-Stroke outboard engines manufactured between 1984 and 2002. It serves as a reliable replacement to restore compression and performance, ensuring your motor runs smoothly.

It directly replaces Yamaha part numbers 6E7-11631-00-97 and 6E7-11631-00, and provides an aftermarket interchange for various Mercruiser and Sierra part numbers.

• Complete assembly includes the piston, rings, wrist pin, and circlips for a full top-end rebuild.
• Manufactured from a durable aluminum alloy to meet or exceed OEM specifications.
• Installation requires engine disassembly and should be performed by an experienced technician.

Part Number Matrix

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

Engine & Model Compatibility

Confirm your engine model/year in the table below.

This part is compatible with a wide range of Yamaha 9.9HP, 13.5HP, and 15HP 2-stroke outboard models.

Technical Specs

Product Type

Piston Kit with Rings

Bore Size

56mm (Standard)

Engine Type

2-Stroke

Material

Aluminum Alloy

Piston Type

Flat Top

Product Dimensions

8.0" L x 6.5" W x 6.5" H

OEM Reference

6E7-11631-00-97, 6E7-11631-00

Fuel Type

Gasoline

Max Horsepower

15HP

What’s in the Box

• 1 x Piston (6E7-11631-00-97)
• 2 x Piston Ring (682-11610-01)
• 2 x Circlip (93450-15023)
• 1 x Piston Pin (634-11633-00)

Installation Notes

Proper installation is critical for engine safety and performance. These are general guidelines; always refer to your engine’s specific service manual for detailed instructions.

1. Disconnect the battery and fuel lines to ensure safety.
2. Remove the engine cover and disassemble the powerhead to access the cylinders.
3. Carefully remove the old piston, wrist pin, and circlips.
4. Clean the cylinder bore and inspect for wear or damage. Hone if necessary.
5. Install the new piston rings onto the new piston, ensuring correct orientation.
6. Attach the piston to the connecting rod using the new wrist pin and circlips.
7. Use a piston ring compressor to carefully guide the piston assembly into the cylinder.
8. Reassemble the engine components in reverse order, torquing all bolts to manufacturer specifications.

Troubleshooting & FAQ

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 with an average transit time of 5–15 days.
• Manufacturer-Direct Value — Fair pricing on reliable parts without compromising on materials or quality control.