John Deere 644K Loader Operation and Test Technical Manual

TABLE OF CONTENTS

General Information
Safety
Recognize Safety Information
Follow Safety Instructions
Operate Only If Qualified
Wear Protective Equipment
Avoid Unauthorized Machine Modifications
Inspect Machine
Stay Clear of Moving Parts
Avoid High-Pressure Fluids
Avoid High-Pressure Oils
Beware of Exhaust Fumes
Prevent Fires
Prevent Battery Explosions
Handle Chemical Products Safely
Dispose of Waste Properly
Prepare for Emergencies
Add Cab Guarding For Special Uses
Start Only From Operator’s Seat
Prevent Unintended Machine Movement

Diagnostic Trouble Codes (DTC)
Operational Checkout Procedure
Engine
Electrical System
Hydraulic System
Hydrostatic System
Theory of Operation
Hydrostatic System
Transmission Control Circuit—Flow Chart
Charge Pump Operation
Hydrostatic Filter Operation
Neutral Charge Relief Valve Operation
Park Brake Operation
Multi-Function Valve Operation
Oil Cooler Bypass Valve Operation
Pump Pressure Control Pilot (PCP) Operation
Pump Displacement Control Valve (PDCV) Operation
Hydrostatic Pump Operation
Flushing Valve and Operating Charge Relief Valve Operation