Yamaha 4X8-11630-10-00 - Piston Kit (1ST O-S) is a genuine Yamaha part. It is an internal engine component built to Yamaha's specification. Ordering by part number 4X8-11630-10-00 ensures you receive the exact component Yamaha lists for its location.

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Key Features & Benefits

• Replaces worn, scored, or damaged engine components.
• Installs in the position shown in the Yamaha engine parts diagram.
• Built to Yamaha's specification for its engine location.
• Size designation 1ST O-S as listed by Yamaha; confirm the required size with service manual measurements.

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Frequently Asked Questions

What is the Yamaha Piston Kit (1ST O-S) (4X8-11630-10-00)?

The Piston Kit (1ST O-S) is a genuine Yamaha part sold under part number 4X8-11630-10-00. This engine part is one of the internal components that keep the engine running as designed.

What does the 1ST O-S size on part 4X8-11630-10-00 mean?

O-S marks an oversize part and U-S an undersize part. Yamaha lists 4X8-11630-10-00 as 1ST O-S, which is used when the mating part has been machined or worn to match. Measure and confirm the required size using the Yamaha service manual.

Where does the Piston Kit (1ST O-S), part 4X8-11630-10-00, fit in the engine?

The Piston Kit (1ST O-S) installs in the engine location shown for part 4X8-11630-10-00 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.