🏷️ Basic Information Identification Make: MerCruiser Engine Family: GM 4 Cylinder Product Type: Service Manual 📋 Manual Details Documentation Manual Type: Factory Service Manual Language: English Format: PDF Delivery Delivery Method: Download Features Repair Instruction Style: Step-by-step Content Illustrations: Photos and Illustrations Purpose: Overhaul and Repair Guide ⚙️ Engine Specifications General Engine Configuration: Inline 4-Cylinder Displacement Displacement Liters: 3.0 Displacement Cid: 181 Power Horsepower Mcm 120: 120 Horsepower Mcm 140: 140 Horsepower Sea Ray 3.0 Later: 130 Compression Ratio Sea Ray 3.0L Later Models: 9.2:1 🔧 Maintenance General Maintenance Specifications Provided: True Disassembly Procedures Covered: True Assembly Procedures Covered: True Inspection Adjustment Procedures Covered: True Troubleshooting Section Included: True 📄 Model Coverage Engine Models Mcm 120 Mr: S/N: 6853914-0A492055 Mcm 120 Alpha I: S/N: OA492056-08531853 Mcm 2.5L: S/N: OC856450 and Above Mcm 140 Mr: S/N: 6852270-0A484072 Mcm 140 Alpha I: S/N: OA484073-08450800 Mcm 3.0L: S/N: OC856450 and Above Sea Ray 3.0L: S/N: 08787205-8917530 Notes Mcm 2.5L Mcm 3.0L Relation: Same as MCM 120 Sea Ray 3.0L Relation: Same as MCM 140 (Later Models are rated at 130 HP) 📄 Service Manual Outline Section 1 Title: Important Information Subsections: • Important Information • Maintenance • Troubleshooting Section 2 Title: Removal & Installation Subsections: • 4 Cyl. 153-181 CID (2.5-3.0L) • Driveshaft Extension Models Section 3 Title: Engine Mechanical Subsections: • G.M. In-Line Section 4 Title: Electrical Systems Subsections: • Starting System • Ignition System • Charging Systems • Instrumentation • Electrical Kits • Wiring Diagrams Section 5 Title: Fuel Systems Subsections: • Fuel Delivery System • Fuel Pump • MerCarb 2-Barrel Section 6 Title: Cooling & Exhaust Subsections: • Seawater Cooled Models • Closed Cooled Models • Exhaust Manifolds/Elbows Section 7 Title: Power Steering Subsections: • Power Steering