Piston Kit (+0.50mm) – Fits Yamaha 9.9/15HP 2-Stroke Outboards (Replaces 6E7-11636-00)

Product Details

This is an aftermarket Piston Kit (+0.50mm) for Yamaha 9.9/15HP 2-Stroke Outboards, designed for engine models from 1984–2006 and later. It is specifically intended for use in engine cylinders that have been machined 0.50mm over the standard bore diameter.

This kit serves as a direct replacement for Yamaha OEM part number 6E7-11636-00-00 and aftermarket interchange part 6E71163600.

• Installs in the engine cylinder block as part of a powerhead rebuild or repair.
• Engineered for 2-stroke gasoline outboard motors.
• Complete kit includes one piston, one piston pin, and two circlips for a full assembly.

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 piston kit is confirmed to fit a wide range of Yamaha 9.9HP and 15HP 2-stroke models manufactured from 1984 through 2006 and later. While this kit may fit some Chinese-made clone engines (like Parsun or Hidea) that use a 56.5mm cylinder, fitment for those brands is not guaranteed. Please verify your engine's specifications before ordering.

Technical Specs

Product Type

Oversize Piston Kit (+0.50mm)

Installation Location

Engine cylinder/powerhead

Compatible Fuel

Gasoline (2-stroke)

Material

Aluminum alloy

Piston Diameter

56.5mm (oversized +0.50mm from standard)

Piston Ring Width

1.96mm

Product Dimensions

Length: 7.8, Width: 5.5, Height: 5.5

Box Dimensions

Length: 7.8, Width: 5.5, Height: 5.5

What’s in the Box

• 1 x Piston (+0.50mm oversize) (Replaces 6E7-11636-00)
• 1 x Piston Pin
• 2 x Circlips

Installation Notes

1. Before ordering, use a caliper to precisely measure your cylinder bore. This oversize piston is only for cylinders machined to 56.5mm.
2. Carefully remove the old piston, pin, and rings from the connecting rod.
3. Thoroughly clean the cylinder walls and connecting rod of any carbon buildup or debris.
4. Lightly lubricate the new piston, pin, and cylinder wall with fresh 2-stroke engine oil before assembly.
5. Install your new piston rings (sold separately) onto the piston, ensuring the ring gaps are correctly positioned per your engine's service manual.
6. Install one circlip, then insert the piston pin through the piston and connecting rod, and secure with the second circlip.
7. Use a piston ring compressor tool to gently and evenly guide the piston assembly back into the cylinder.
8. Always refer to your outboard's official service manual for detailed procedures, torque specifications, and safety precautions.

Troubleshooting & FAQ

Safety & Important Info

• Verify images and specifications against your original part before purchase. If anything differs—even if your model appears compatible—do not order.
• This is an aftermarket replacement component, not an OEM part.
• Professional installation is recommended for safety and performance.

About Sea Sierra

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