Yamaha 7UD-E1635-00-00 - Piston (0.25MM O-S) is a genuine Yamaha part. This engine part is one of the internal components that keep the engine running as designed. Use part number 7UD-E1635-00-00 to confirm it matches the component shown in your model's Yamaha parts diagram.

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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 0.25MM O-S as listed by Yamaha; confirm the required size with service manual measurements.

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Frequently Asked Questions

What is Yamaha part 7UD-E1635-00-00?

7UD-E1635-00-00 is the Yamaha part number for the Piston (0.25MM O-S), a genuine Yamaha part. It replaces a worn or damaged engine component with the specified Yamaha part.

What does the 0.25MM O-S size on part 7UD-E1635-00-00 mean?

O-S marks an oversize part and U-S an undersize part. Yamaha lists 7UD-E1635-00-00 as 0.25MM 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.

Should related parts be replaced with the Piston (0.25MM O-S), part 7UD-E1635-00-00?

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 7UD-E1635-00-00.

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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.