357 Alpha 4V

275 Crankshaft Horsepower

Don't just repower--power up! The world famous 357 Alpha will breathe new life into your runabout, sport boat or pontoon boat when replacing a 4.3L, 5.0L, or 5.7L engine.

1-Year Factory Warranty

Available when purchased through any Mercury/MerCruiser authorized dealer

2 Additional Years of Coverage

Available from Mercury Product Protection



Part Number 865108R88
Horsepower @ flywheel 275
Kilowatts @ flywheel 205
Maximum RPM (WOT) 4400-4800
Cylinders V-8 Remanufactured Iron Marine Block
Displacement (CID/L) 357 / 5.8
Bore & Stroke (in/mm) 4.04 x 3.48in
103 x 88mm
Compression Ratio 9.4:1
Fuel / Ethanol Tolerance 87 octane / up to 10% ethanol
Engine Control System Thunderbolt V w/Knock Control
Fuel Delivery System 4V carburetor and mechanical fuel pump
Fuel Injection System / Carburetor Type 750 cfm Weber 4V with electric choke
Induction System Dual plane aluminum intake manifold with brass water crossover
Charging alternator amp 65
Charging alternator watt 917
Water drain system Multi-point drain
Exhaust System Electro-deposition paint coated warm iron manifold with wet joint elbow
Cooling System 160F Raw Water Alpha
Accessory Drive System Serpentine belt
Lubrication System High Flow 60 psi Oil Pump
Recommended Oil Mercury MerCruiser Synthetic Blend 25W-40, NMMA FC-W rated
Pistons Cast Hypereutectic Alloy
Cranktrain Powder Metal Rods and Nodular Iron Crankshaft
Rocker Arms 1.5:1 Stamped Steel
Length (in/mm) 32in / 814mm
Width (in/mm) 30in / 740mm
Height (in/mm) 22in / 559mm
Weight (lbs/kg) 871lbs / 395kg
Features & Related Products Analog Controls
Analog Gauges
Full closed cooling (KIT)
Hydraulic / Power steering
Remote Oil filter
Compatible Drives (Application Dependant - Contact Sales or Service) Alpha 1.47:1
Alpha 1.81:1

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