Yamaha 4NX-11631-00-00 - Piston (Std) is a genuine Yamaha part. It is an internal engine component built to Yamaha's specification. Confirm part number 4NX-11631-00-00 against your Yamaha parts diagram before ordering.

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Key Features & Benefits

• Built to Yamaha's specification for its engine location.
• Replaces worn, scored, or damaged engine components.
• Installs in the position shown in the Yamaha engine parts diagram.
• Size designation Std as listed by Yamaha; confirm the required size with service manual measurements.

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Frequently Asked Questions

Is 4NX-11631-00-00 a genuine Yamaha part?

Yes. 4NX-11631-00-00 is the Yamaha part number for the Piston (Std). This engine part is one of the internal components that keep the engine running as designed.

What does the Std size on part 4NX-11631-00-00 mean?

STD indicates the standard-size version of part 4NX-11631-00-00. Oversize or undersize versions are listed separately for use after machining or when wear calls for them; confirm the size you need using the Yamaha service manual.

Should related parts be replaced with the Piston (Std), part 4NX-11631-00-00?

When replacing engine internals, inspect mating parts and replace gaskets and seals disturbed during disassembly. Refer to the Yamaha service manual for your model when installing 4NX-11631-00-00.

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WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer, birth defects or other reproductive harm. For more information go to P65Warnings.ca.gov.