Yamaha 4JT-11631-31-C0 - Piston (Std) is a genuine Yamaha part. It replaces a worn or damaged engine component with the specified Yamaha part. Confirm part number 4JT-11631-31-C0 against your Yamaha parts diagram before ordering.

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Key Features & Benefits

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

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Frequently Asked Questions

What part does Yamaha number 4JT-11631-31-C0 refer to?

Yamaha number 4JT-11631-31-C0 identifies the Piston (Std), a genuine Yamaha part. It is an internal engine component built to Yamaha's specification.

What does the Std size on part 4JT-11631-31-C0 mean?

STD indicates the standard-size version of part 4JT-11631-31-C0. 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.

Where does the Piston (Std), part 4JT-11631-31-C0, fit in the engine?

The Piston (Std) installs in the engine location shown for part 4JT-11631-31-C0 in the Yamaha parts diagram for your model.

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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.