Mercury Marine manufactures MerCruiser 4.3L engines as well as the MerCruiser Alpha One sterndrive. A marine engine delivers power to the propeller by means of a sterndrive unit, which sits in the water attached to the aft end of the boat. When coupled together, a MerCruiser 4.3L engine and Alpha One sterndrive propel the vessel through the water.
MerCruiser 4.3L MPI Engine
The MerCruiser 4.3L MPI engine is a multi-point, fuel injected engine. This V6, 262 cubic inch (4.3-liter) motor delivers 220 horsepower (HP) to the sterndrive at 4,400 to 4,800 RPM at WOT (wide open throttle). With a compression ratio of 9.4:1, it runs on 87 octane gasoline. Electrical components are powered by a 65 amp, 917 watt alternator. The engine connects to the MerCruiser Alpha One sterndrive with drive ratios of 1.47:1, 1.62:1 and 1.81:1. These varying ratios are achieved by means of the transmission integrated into the sterndrive, indicating the number of revolutions of the propeller per one revolution of the engine. The ratios vary according to which gear the transmission is in. The engine and stern drive weigh 865 lbs. when coupled together.
MerCruiser 4.3L TKS Engine
The MerCruiser 4.3L TKS engine is a 190 HP, 262 cubic inch (4.3-liter) V6 engine with a 2-barrel carburetor instead of fuel injections like its MFI cousin. It uses 87 octane fuel to turn the engine to a maximum of 4,400 to 4,800 RPM at WOT. It also uses a 65 amp, 917 watt alternator. It connects to the Alpha One sterndrive with drive ratios of 1.62:1, 1.81:1 and 2.0:1. The total weight of the engine and stern drive is 848 lbs.
The MerCruiser Alpha One Sterndrive
The MerCruiser Alpha One sterndrive has a maximum power capacity of 300 HP, a maximum propeller size of 15 inches, and a top speed of 65 MPH. Its transmission is forward, reverse and neutral selectable. The Alpha One has a maintenance free U-joint, adjustable power trim, 56-degree steering range and a total weight of 85 lbs. The mechanics of the unit are housed in a corrosion resistant, aluminum low-copper alloy, which is triple painted.
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