MerCruiser sterndrive (gas, 4.5L–6.2L)
The most common inboard/outboard in US bowriders and cruisers. The engine itself (GM-based) is reliable; the maintenance burden is the drive and exhaust. Bellows, gimbal bearing, U-joints, and — in any saltwater service — exhaust manifolds and risers are the recurring costs.
Service and what to check
Bellows/gimbal every ~5 years; manifolds/risers every ~6–8 years (or 3–4 in salt) at $2.5–4K. Pull the drive on inspection — deferred drive service is the classic hidden cost.
Watch usage: above roughly 100 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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