Replacing a marine engine is a big decision. You need a powerplant that fits your boat's existing mounts, wiring, and drive system-and you don't want to spend weeks chasing missing parts. If you're shopping for a proven small-block V8, the MerCruiser Marine 5.7L 350 V8 reman inboard engine often shows up as a "drop in ready" solution. But what exactly does that include? Let's look at what this engine actually offers and who it makes sense for.
Quick verdict
The MerCruiser Marine 5.7L 350 V8 reman inboard engine is aimed at boat owners replacing a small-block V8 with a fresh-water, clockwise-rotation powerplant. At $4,999, it's a straightforward buy if you already have a transmission, coupler, and supporting accessories-because this engine ships without the transmission, and you'll need to transfer or source one separately.
Who it suits
This engine fits DIY repower projects where the boat's existing transmission, bell housing, and engine mounts are still usable. Because it's described as "drop in ready," it should align with existing motor mounts and stringers, though you'll still need to connect cooling, fuel, and electrical systems. It's also a reasonable option if you know your boat requires a CW (right-hand) rotation engine-this one is specifically configured that way.
What stands out from the listed details
The engine is described as a fresh-water unit, which is good news if your boating is exclusively in lakes or rivers. The 5.7L 350 V8 is a familiar small-block design with aftermarket and OEM support, so replacement parts and service information are easy to find. The "reman" status suggests a rebuilt unit rather than a new crate engine, and the phrase "runs great" in the description indicates it's been checked and prepared for installation. Another helpful detail: the bell housing is still attached, which is one less component you'll need to source when replacing your old engine.
The $4,999.00 price point puts this in a specific range for a rebuilt small-block marine engine. At that price, you're not paying for a full package of manifolds, risers, and a transmission-you're paying for the base engine with the bell housing mounted.
Meaningful trade-offs
The most obvious omission is the transmission. The description explicitly says the transmission is removed and not included. If you plan to reuse your old transmission, make sure its input shaft, mounting pattern, and rotation direction match this engine's output. The engine is CW rotation-most MerCruiser inboards use right-hand rotation when viewed from the rear-but you should confirm your drive and prop are set up for that direction. Also, because this is a used reman unit, you'll want to inspect the engine's condition beyond the description. The $4,999 price covers the engine as described, but you may want to budget for gaskets, fluids, or a new intake gasket set depending on how long it's been sitting. Freshwater use typically means less corrosion, but a pre-installation inspection is still a prudent step.
Product note
MerCruiser Marine 5.7L 350 V8 Reman Inboard Engine
The listed price for this fresh-water drop-in-ready engine is $4,999.00. It's described as running great and being ready to drop into your boat. The bell housing is included, but the transmission is not. This is a CW (right-hand) rotation engine, so it should match standard inboard setups that use clockwise rotation when viewed from behind. Choose this if you already have a transmission and want a well-known small-block V8 that's ready to install. Skip it if you need a complete drivetrain-you'll have to source the transmission separately, which adds time and cost.
Bottom line
If your boat is already set up for a small-block V8 with a separate transmission, the MerCruiser Marine 5.7L 350 V8 reman inboard engine offers a well-known, easily supported platform at a concrete $4,999 price point. It's not a complete repower kit-the transmission is your responsibility-but it is a credible choice for an experienced boat owner or shop that wants a fresh-water, clockwise-rotation engine ready to drop into a clean installation.
