Yamaha YF1-56942-39-40 - Crankshaft Metal (2ND U-S) is a genuine Yamaha part. It replaces a worn or damaged engine component with the specified Yamaha part. Ordering by part number YF1-56942-39-40 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 2ND U-S as listed by Yamaha; confirm the required size with service manual measurements.
• Sold under Yamaha part number YF1-56942-39-40.

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Frequently Asked Questions

What part does Yamaha number YF1-56942-39-40 refer to?

Yamaha number YF1-56942-39-40 identifies the Crankshaft Metal (2ND U-S), a genuine Yamaha part. It is an internal engine component built to Yamaha's specification.

What does the 2ND U-S size on part YF1-56942-39-40 mean?

O-S marks an oversize part and U-S an undersize part. Yamaha lists YF1-56942-39-40 as 2ND U-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 Crankshaft Metal (2ND U-S), part YF1-56942-39-40?

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 YF1-56942-39-40.

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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.