Hyundai Robex 55-3, R55-3 Crawler Excavator - Comprehensive Service & Repair Manual, covers 1997-2002

Hyundai Robex 55-3 R55-3 Crawler Excavator Service Manual - 1997-2002

Engineering and maintenance personnel require exact technical data to ensure the structural integrity and operational efficiency of the Robex 55-3 series. This manual provides the factory-sanctioned procedures for complex system overhauls, including high-precision settings for the variable displacement double-piston main pump and 9-spool control valves. Utilizing the specific ISO VG 46 hydraulic oil grade is critical for maintaining system viscosity between 15 and 150 mm²/s, preventing cavitation and ensuring the responsive actuation of the 10 rpm swing motor under heavy load.

Dynamic Infrastructure: Models & Components Covered

• Manufacturer: Hyundai Heavy Industries Co., Ltd.
• Model Series: Robex 55-3 (R55-3) Crawler Excavator
• Production Range: Covers machine serial numbers up to #1539 and above.
• System Architecture: Detailed coverage for Yanmar 4TNE94 diesel engines, variable displacement piston pumps, and 2-stage planetary reduction gears.

Operational Advantage: Safety and System Longevity

• Performance Restoration: Periodic testing protocols using "Service Limits" allow technicians to identify component deterioration before catastrophic failure occurs.
• Hydraulic Integrity: Precise relief valve settings—210 kgf/cm² for main relief and 230 kgf/cm² for overload—protect the system from pressure surges during intense digging cycles.
• Safety Compliance: Integrated safety hints and "Do Not Operate" tagging procedures ensure a secure workspace during pressurized system maintenance.

Documentation Specifications: Technical Metadata

• Manual Type: Service / Workshop Manual
• Language: US English
• Total Volume: 328 Pages
• Reference Codes: R55NM-series technical identifiers.

Technical Depth & Factory Benchmarks

Diagnostic procedures are anchored by rigorous standard specifications, such as the 18:1 compression ratio of the Yanmar 4TNE94 engine and its rated gross power of 58.5 Ps at 2500 rpm. Performance evaluation requires high idling speeds set at 2600 ± 50 rpm, while hydraulic cylinder cycle times for boom raising are benchmarked at 2.4 ± 0.4 seconds to ensure factory-level productivity.

Visual Navigation Aids & System Mapping

• Hydraulic Schematics: Comprehensive circuit diagrams segmented by serial number ranges (e.g., up to #374 and #0617 and up) facilitate rapid troubleshooting of the RCV levers and travel motors.
• Exploded Assembly Views: Disassembly guides for the main pump and travel motors illustrate every snap ring, friction plate, and planetary gear to prevent assembly errors.
• Component Location Matrix: Electrical system maps identify hour meters, battery relays, and sensor locations (e.g., water temperature switches) for efficient electrical tracing.

Table of Contents

• Section 1: General: Safety Hints and Major Component Specifications.
• Section 2: Structure and Function: In-depth analysis of Pump, MCV, and Power Train.
• Section 3: Testing and Adjusting: Operational Performance and Pressure Testing.
• Section 4: Electrical System: Circuit Diagrams, Operation, and Monitoring.
• Section 5: Troubleshooting: Logic trees for Electrical and Hydraulic Failures.
• Section 6: Maintenance Standard: Wear Limits and Repair Criteria for Under Carriage and Work Equipment.
• Section 7: Disassembly and Assembly: Step-by-step Overhaul Procedures for all major assemblies.

Operational Limits & Engineering Specifications

• Torque Sequences: Main pump cover bolts require 10–12.5 kgf·m, while travel motor machine installation bolts must be torqued to 25.7 ± 4.0 kgf·m.
• Wear Limits: Track shoe link pitch repair limit is set at 138 mm (from a standard 135 mm), and idler guide vertical width must be rebuilt if it reaches 86 mm.
• Fluid Capacities: Engine oil pan (9.7 liters), Hydraulic tank (80 liters), and Final drive (1.7 liters per side).