Case Wheel Loader 621E TIER 3 Service Manual PDF

This workshop manual covers the Case 621E Tier 3 wheel loader. It explains the machine’s main systems and provides service specifications, troubleshooting procedures, and step-by-step instructions for component removal and installation.

The manual is intended for qualified service personnel. Follow the manufacturer’s instructions and observe the specified service procedures and safety precautions when performing repairs and maintenance.

Service and Repair Coverage

The manual covers engine and radiator removal and installation, stall tests, electrical systems, starter and alternator replacement, batteries, and instrument cluster servicing. It also includes steering system repairs, pressure checks, steering cylinders, center pivot, and auxiliary steering components.

The power train section covers the transmission, front and rear axles, drive shafts, universal joints, wheels and tires, and the transmission control valve. Brake system information includes hydraulic brake troubleshooting, brake pump, brake accumulators, and parking brake servicing.

The hydraulic section explains how to read hydraulic schematics and includes hydraulic specifications, pressure checks, troubleshooting, system cleaning, loader control valve, cylinders, coupler solenoid locking valve, and ride control components.

Additional coverage includes air conditioning and heater systems, mounted equipment, loader components, ROPS and cab structural frame, cab glass installation, and electrical and hydraulic schematic foldouts.

521E Wheel Loader
Service Manual
84243970 (Replaces 87728450)

Table of Contents

Description
General
Section Index - General
Standard Torque Specifications
Fluids and Lubricants
Metric Conversion Chart

Engines
Section Index - Engines
Engine and Radiator Removal and Installation
Stall Tests
After Cooler
For Engine Repair, See the Engine Service Manual

Fuel System
Section Index - Fuel System
For Fuel System Repair, See the Engine Service Manual

Electrical
Section Index - Electrical
Removal and Installation of Starter and Alternator
Electrical Specifications and Troubleshooting
Batteries
Instrument Cluster

Steering
Section Index - Steering
Removal and Installation of Steering Components
Steering Specifications, Pressure Checks, and Troubleshooting
Steering Cylinders
Center Pivot
Auxiliary Steering Motor and Pump
Joystick Steering

Section Index - Power Train
Removal and Installation of Power Train Components
Transmission Specifications, Pressure Checks, and Troubleshooting
Transmission
Front Axle
Rear Axle
Drive Shafts, Center Bearing, and Universal Joints
Wheels and Tires
Transmission Control Valve

Brakes
Section Index - Brakes
Removal and Installation of Brake Components
Hydraulic Brake Troubleshooting
Brake Pump
Brake Accumulators
Parking Brake

Hydraulics
Section Index - Hydraulics
How to Read Hydraulic Schematics
Removal and Installation of Hydraulic Components
Hydraulic Specifications, Troubleshooting, and Pressure Checks
Cleaning the Hydraulic System
Loader Control Valve
Cylinders
Coupler Solenoid Locking Valve
Ride Control Accumulator
Ride Control Valve

Description
Mounted Equipment
Section Index - Mounted Equipment
Air Conditioning Troubleshooting and System Checks
Air Conditioner System Service
Removal And Installation Of Air Conditioning And Heater Components
Loader
Roll Over Protective Structure (ROPS), Cab Structural Frame (CSF)
Cab Glass Installation
Electrical Schematic Foldouts and Hydraulic Schematic Foldout

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Printing and Customer Support

The entire PDF manual is ready for printing, allowing you to print only the instructions relevant to your current task and keep them handy in your workshop.

If you have any questions about the manual or need assistance with your order, feel free to contact our support team. We provide after-sales support to help you with any issues.