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Caterpillar hydraulic excavators serie D
SERV1852-02 October 2008 GLOBAL SERVICE LEARNING TECHNICAL PRESENTATION 320D-336D HYDRAULIC EXCAVATORS TIER III ENGINES DEMAND FAN SYSTEMS Service Training Meeting Guide (STMG) 320D-336D HYDRAULIC EXCAVATORS TIER III ENGINES DEMAND FAN SYSTEMS AUDIENCE Level II - Service personnel who understand the principles of machine systems operation, diagnostic equipment, and procedures for testing and adjusting CONTENT This presentation provides an introduction and describes the components and systems operation of the 320D-336D hydraulic excavator demand fan systems Additional presentations will cover the machine walkaround, engines, pilot system, main control valve group, implements, swing system, travel system, and tool control systems in more detail This presentation may be used for self-paced and self-directed training OBJECTIVES After learning the information in this presentation, the technician will be able to: identify the correct operation of the demand fan systems used on the 300D Series hydraulic excavators for engine cooling, and diagnose problems in the fan systems REFERENCES 320D Hydraulic Excavator Specalog 323D L and 323D LN Hydraulic Excavators 324D Hydraulic Excavator Specalog 325D Hydraulic Excavator Specalog 328D Hydraulic Excavator Specalog 330D Hydraulic Excavator Specalog Machine Monitoring System - Systems Operation Self-study "300D Series Hydraulic Excavators, 345C Hydraulic Excavator, and 365C & 385C Large Hydraulic Excavators iTIM " '300C' Series Hydraulic Excavators-Electronic Control Systems" iTIM "325C Hydraulic Excavators-Hydraulic Systems" 325D Hydraulic Schematic Estimated Time: Hour Illustrations: 41 Form: SERV1852-02 Date: September 2008 © 2008 Caterpillar AEHQ5856 HEHH3327 AEHQ5663 AEHQ5665 AEHQ5706 AEHQ5667 RENR8068 SERV7032 SERV2693 SERV2701 KENR6157 SERV1852-02 10/01 -3- Text Reference Demand Fan Systems TABLE OF CONTENTS INTRODUCTION HYDRAULIC DEMAND FAN SYSTEM Cat ET Screens for the Hydraulic Cooling Demand Fan .19 Monitor Screens for the Hydraulic Cooling Demand Fan 20 VISCONIC DEMAND FAN SYSTEM (ATTACHMENT) .33 Cat ET Screens for the Visconic Cooling Demand Fan .46 Monitor Screens for the Visconic Cooling Demand Fan .51 CONCLUSION 52 SERV1852-02 10/01 -4- Text Reference Demand Fan Systems PREREQUISITES "Fundamentals of Mobile Hydraulics Self Study Course" "Fundamentals of Power Train Self Study Course" "Fundamentals of Electrical Systems Self Study Course" "Fundamentals of Engines Self Study Course" TEMV3002 TEMV3003 TEMV3004 TEMV3001 NOTES Nomenclature Change: During the fourth quarter of 2008, the 325D and 330D nomenclature changed The 325D became the 329D and the 330D became the 336D for most arrangements The exceptions are as follows: - The nomenclature for the 325D MH and 330D MH did not change - The nomenclature for the 325D FM and 330D FM did not change - The 325D HD HW did not change into 329D HD HW This model is being discontinued However, the 330D HD HW changed to the 336D HD HW SERV1852-02 10/01 -5- Text Reference Demand Fan Systems 320D - 336D EXCAVATORS - TIER III ENGINES DEMAND FAN SYSTEMS © 2008 Caterpillar INTRODUCTION There are two types of demand systems used on the 320D-336D Hydraulic Excavator to control the cooling fan for the engine: - Hydraulic demand fan system (330D/336D Only): The hydraulic demand fan system is made up of a fan motor and fan pump to cool the hydraulic oil, engine radiator, fuel cooler, and the ATAAC A reversing fan attachment is available for the hydraulic demand fan system - Visconic demand fan system (320D, 321D, 323D, 324D, 325D, 328D and 329D): The visconic demand fan system uses a viscous coupling between the engine mounted, belt driven fan drive hub and the fan assembly NOTE: The cooling fan viscous coupling is sometimes called the fan clutch A fan clutch is a thermostatically-controlled device When the engine is cool or even at normal operating temperature, the fan clutch partially disengages the engine's mechanically-driven cooling fan This decoupling saves power since the engine does not have to fully drive the fan If engine temperature rises above the fan clutch's engagement temperature setting, the fan becomes fully engaged, When the fan clutch is fully engaged, the fan draws a higher volume of ambient air through the radiator, which in turn serves to maintain or lower the engine coolant temperature to an acceptable level SERV1852-02 10/01 -6- Text Reference Demand Fan Systems Coolant Temp Sensor Fill Cap Coolant Expansion Tank Radiator Intake Manifold Air Temperature Sensor Thermostat Housing To Cylinder Block Coolant Bypass Tube Water Pump ATAAC Top Tank Cab Heater Fan Motor Hottest > 92 C Increasing Coolant Temperature 87 C Coldest < 81 C Engine Oil Cooler Engine ECM Monitor Machine ECM CAN Data Link Hydraulic Oil Cooler Slow Return Check Valve CDL Case Drain Filter Fan Drive Pump OK Main Return Filter Hydraulic Oil Temp Sender Hydraulic Circuits 330D/336D HYDRAULIC DEMAND FAN COOLING SYSTEM ENGINE AT OPERATING TEMPERATURE HYDRAULIC DEMAND FAN SYSTEM The hydraulic demand fan system is made up of a fan motor and fan pump to cool the hydraulic oil, engine radiator, fuel cooler, and the ATAAC The electronically controlled, variable displacement, piston fan pump is driven off of the main hydraulic system drive pump The fan pump flow output is controlled by the angle of the swashplate A solenoid on the fan pump receives a PWM signal from the Machine ECM to control the pump swashplate When the machine is running, the hydraulic oil temperature sender and the engine coolant temperature sensor sends signals to the Engine ECM The Engine ECM then sends this information to the Machine ECM The Machine ECM picks up the hydraulic temperature through the monitor SERV1852-02 10/01 -7- Text Reference Demand Fan Systems The Machine ECMs interpret the information from these inputs to send a PWM signal to the fan pump solenoid to control the angle of the pump swashplate to control the pump flow A higher temperature input will cause the Machine ECM to send a reduced PWM signal to the fan pump solenoid The reduced signal causes the pump to upstroke to increase pump flow, which increases the speed of the fan for more cooling capacity SERV1852-02 10/01 -8- Text Reference Demand Fan Systems The variable displacement fan pump is driven off of the drive pump, which is part of the main pump group (2) The pump control valve group (3) features a pressure control solenoid (4), which is controlled by the Engine ECM The pump control valve group has two adjustment screws: - The upper screw, next to the pump control solenoid, is below the cap (5) This screw is used to adjust the pump control spool - The lower screw (6), below the pump control valve group, is used to adjust the pressure control spool The reservoir supply line (7) is below the fan pump housing, while the pump supply line (8) to the motor is above the housing NOTE: In most cases, the two adjustment screws should not be used The solenoid can be calibrated through Cat ET or the monitor to correctly set the fan pump control SERV1852-02 10/01 -9- Text Reference Demand Fan Systems The 330D/336D engine fan (1) is hydraulically driven by a fixed displacement motor (2) The variable displacement fan pump supplies oil to rotate the fan motor Fan speed is varied to provide optimized cooling The optimum fan speed is calculated using engine coolant temperature and hydraulic oil temperature Case drain oil from the fan motor is combined with the case drain oil from the swing and travel motors Return oil from the fan motor is sent to the return filters and into the hydraulic tank An internal makeup valve in the fan motor is used to prevent cavitation when flow from the fan pump stops The direction of the engine fan can be reversed on machines equipped with the reversible fan option The fan motor rotation can be changed with the monitor The reversal of the fan motor is used to clear debris and dust from the radiator and hydraulic oil cooler SERV1852-02 10/01 - 10 - Text Reference Demand Fan Systems The radiator access compartment is located in front of the counterweight The door is hinged on the right and has a locking latch on the left side to keep it closed This door provides access for cleaning some of the cooling system components as servicing some of the fuel system and cooling system components - hydraulic oil cooler (1) - Air to Air After Cooler (ATAAC) (2) - radiator (3) - engine coolant overflow bottle (4) ... change - The nomenclature for the 32 5D FM and 33 0D FM did not change - The 32 5D HD HW did not change into 32 9D HD HW This model is being discontinued However, the 33 0D HD HW changed to the 33 6D HD... SERV185 2-0 2 10/01 -5 - Text Reference Demand Fan Systems 32 0D - 33 6D EXCAVATORS - TIER III ENGINES DEMAND FAN SYSTEMS © 2008 Caterpillar INTRODUCTION There are two types of demand systems used on... 32 5D and 33 0D nomenclature changed The 32 5D became the 32 9D and the 33 0D became the 33 6D for most arrangements The exceptions are as follows: - The nomenclature for the 32 5D MH and 33 0D MH did