Yamaha 425 XTO Offshore
Yamaha's flagship 5.6L V8. Strong and well-supported, but a maintenance-cost premium over the 300-class and a 100-hour service interval that owners skip at their peril. Common on triples/quads where total service cost multiplies.
Service and what to check
100-hour service is mandatory; the electric steering and integrated rigging are dealer-serviced. Verify warranty status (typically 5 yr) and what transfers.
Watch usage: above roughly 175 hours/year, this family starts losing reliability points — always weigh total hours against the boat's age, and on any outboard or I/O over a few years old, insist on a compression or leak-down test before money moves.
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