90-857138 Service Manual – Mercury/Mariner 4-5 HP 4-Stroke

90-857138 Service Manual Overview

The 90‑857138 Service Manual is the official factory-issued guide for Mercury/Mariner 4 and 5 HP 4‑Stroke outboard engines, beginning with serial numbers 0R000001 and above. Published in January 1999 by Mercury Marine, this OEM manual spans 8 detailed sections crafted to support both routine maintenance and complex repairs. It includes step-by-step instructions and exploded diagrams with no missing pages, delivering full coverage across all engine systems.

Models & Coverage

While focused on the 4 and 5 HP 4‑stroke models, this manual’s design also benefits similar small-engine platforms, providing versatile value to mechanics and DIYers alike.

Technical Features & Content

This comprehensive guide includes:

• Detailed exploded diagrams and system schematics

• Sequential service procedures covering powerhead, fuel system, ignition, electrical systems, carburetor, cylinder block, midsection, lower unit, and linkage

• Torque specifications, service intervals, and troubleshooting procedures designed for professional or hobbyist application

Condition & Format

Available as:

• A used printed manual, in good condition with complete content and intact visuals.

• Digital download (where available), offering instant, searchable access for convenience and long-term reference.

Arizona Outboard Dismantlers supplies authentic marine manuals trusted by professionals and DIY enthusiasts alike. The 90-857138 Service Manual delivers the factory-level clarity and systems detail you need to confidently tackle engine servicing.