MerCruiser 3.7 L 170 HP 470 4 Cyl Marine Engine

FOR SALE MerCruiser 3.7 L 170 HP 470 4 Cyl Marine Engine NO SALT Drop In Ready 461 HRS. Very excellent condition with low HOURS and great runs.

The MerCruiser 3.7 L (also known as the “470”) is a carbureted inline-4 marine engine that produces 170 HP. Known for its unique design, it features an aluminum engine block paired with a Ford 460 V8 cylinder head.

Core Specifications

• Engine Type : Inline 4-cylinder, 4-stroke
• Displacement : 3.7 L (224 cubic inches)
• Horsepower : 170 HP
• Cylinder Bore : 4.360 inches
• Stroke : 3.750 inches
• Compression Ratio : 8.2:1
• Fuel System : 2-barrel carburetor (typically a Mercarb or Rochester)
• Cooling System : Closed-loop liquid cooling system
• Ignition Timing : 8° Before Top Dead Center (BTDC) @ 650 RPM
• Idle Speed : 650–700 RPM in forward gear
• Spark Plug : CH-RV9YC/RBL9Y
• Spark Plug Gap : 0.035 inches

Fluid & Capacities

• Engine Oil Capacity : 4.5 Quarts (with filter)
• Recommended Oil : SAE 30 or SAE 25W-40 (Marine-grade)
• Coolant Capacity : ~12 Quarts (50/50 mixture of ethylene glycol and water)
• Firing Order : 1-3-4-2

Torque Specifications

• Cylinder Head Bolts : 130 ft-lbs (Must be torqued in a 3-stage sequence: first at 55 ft-lbs, second at 90 ft-lbs, and final at 130 ft-lbs)
• Rocker Arm Bolts : 20 ft-lbs (with valves completely closed)
• Intake Manifold Bolts : 25 ft-lbs.
• Exhaust Manifold/Elbow Bolts : 25 ft-lbs.
• Spark Plugs : 18–22 ft-lbs