This comprehensive MerCruiser 4 cylinder engine service repair manual covers models manufactured between 1985 and 1989, providing detailed information for servicing and overhauling these engines. The manual includes specific instructions for the following models: * MCM 170 MR Serial Numbers 6916779 to 0A475151 * MCM 170 Alpha One Serial Numbers 0A475152 to 0B434940 * MCM 165 Alpha One Serial Numbers 0B424941 to 0B774251 * MCM 3.7L Alpha One Serial Numbers 0B774252 and Above * MCM 190 MR Serial Numbers 6917368 to 0A475551 * MCM 190 Alpha One Serial Numbers 0A475552 to 0B436390 * MCM 180 Alpha One Serial Numbers 0B436391 to 0B775248 * MCM 3.7 Liter LX Alpha One Serial Numbers 0B775249 and Above. The manual's content is designed for technicians familiar with MerCruiser motors and components, covering a wide range of repair tasks from basic maintenance to complete engine overhaul. Detailed descriptions, illustrations, diagrams, troubleshooting guides, and specifications are included to ensure a thorough understanding of each procedure.

The 1985-1989 MerCruiser 4 Cylinder Engine Service Repair Manual is an indispensable resource for boat owners and mechanics seeking comprehensive guidance on maintaining and repairing MerCruiser's popular four-cylinder engines. This manual covers a wide range of models produced during this era, including the renowned 140, 170, and 188 horsepower options. It is a treasure trove of technical information, offering detailed instructions, schematics, and troubleshooting tips to ensure safe and efficient operation of these powerful marine engines. From basic maintenance tasks like oil changes and spark plug replacements to complex repairs involving fuel systems, electrical components, and engine overhauls, this manual provides step-by-step procedures and illustrations that simplify even the most challenging tasks. The manual's value lies in its ability to empower owners and mechanics alike. It serves as a comprehensive guide to understanding the inner workings of MerCruiser 4-cylinder engines, enabling informed decision-making during maintenance and repair processes. Its detailed diagrams and specifications provide a clear visual representation of engine components, facilitating accurate diagnosis and troubleshooting of issues. By offering practical advice and preventative measures, the manual fosters a proactive approach to engine care, ensuring longevity and optimal performance. Whether you're a seasoned boat owner or a novice mechanic, this service repair manual is an essential tool for ensuring the reliable and enjoyable operation of your MerCruiser 4-cylinder engine for years to come.