🏷️ Basic Information Identification Make: Mercury Mercruiser Model: Number 4 Stern Drive Units Years Covered: 1978, 1979, 1980, 1981, 1982 Generation: Early MCM Series 📋 Manual Details Documentation Manual Type: Workshop Service Repair Manual Language: English Format: PDF Delivery Method: Instant Download Compatibility: All Versions of Windows & Mac Required Software: Adobe PDF Reader ⚙️ Engine Specifications Model Range Covered Engine Models: MCM 120, MCM 140, MCM 165, MCM 470, MCM 485, MCM 898, MCM 228, MCM 260 Serial Number Range Serial Numbers: 4891650 to 6216686 Engine Type Engine Type: Marine Inboard/Outboard (Stern Drive) 🔧 Transmission Stern Drive Unit Type: Number 4 Stern Drive Gear Housing Gear Reduction Ratios: Varies by engine model, refer to manual 🔧 Maintenance General Maintenance Service Focus: Service and Repair Fluids Gear Lube Type: Refer to manual for specific type and viscosity Power Trim Fluid Type: Refer to manual for specific type 📄 Manual Content Repair Procedures Major Sections: General Information, Troubleshooting, Drive Unit, Drive Shaft Housing Assembly, Gear Housing Assembly, Transom Plate Assembly, Power Trim, Power Steering, Service Bulletins Diagrams Included: High Quality Target Audience: Do-It-Yourselfer 📄 Performance Engine Power Power Range: 120 HP to 260 HP 📄 Documentation Printability Print Capability: All pages are printable