Service Training SERV2717 November 2001
STUDENT MATERIALS
740
PART OF TECHNICAL INSTRUCTION MODULE SERV2717
740 ARTICULATED TRUCK POWER TRAIN
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Student Materials
MODULE OBJECTIVES All the following objectives require a Caterpillar 740 Articulated Truck. At the completion of this module, you will be able to: 1. Given the the appropriat appropriatee service service manual manual module, module, locate locate and identif identify y the power train hydraulic system components and record the answers on the Lab A Worksheet. 2. Given the the appropriat appropriatee service service manual manual module, module, perform perform the the power train hydraulic system tests on the machine and an d record the results on the Lab B Worksheets. 3. Given a machine, machine, perform perform the torque torque convert converter er stall stall test test during during a lab exercise. 4. Given class class notes notes and reference reference material material,, explain explain the functions functions of the power train hydraulic components during a posttest. 5. Given class class notes notes and reference reference material material,, identify identify the the selector selector and pressure control valve components on a graphic cutaway during a posttest. 6. Given class class notes notes and reference reference material material,, correctly correctly answer answer power power train train hydraulic system operation multiple choice questions on a posttest. 7. Given a 740 Articul Articulated ated Truck, Truck, the appropri appropriate ate service service manual module, class notes, and the case study worksheets, list the possible answers during each step of the troubleshooting process.
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Student Materials
Lab A: Power Train Hydraulic System Component Identification BACKGROUND INFORMATION
MATERIALS NEEDED
This lab measures your ability to identify the Power Train Hydraulic System components for the 740 Articulated Truck.
______Class notes ______Lab A Worksheets ______740 Articulated Truck ______Mechanic's tool box with hand tools ______Pen or pencil
INDIVIDUAL EXERCISE
Use the "Lab A: Power Train Hydraulic System Component Identification Worksheet No. 1" during the presentation to take notes on the location and function of each component. In the lab, use Lab A Worksheet No. 1 to identify the power train system components by matching the lettered or numbered tags on the components with the names on the worksheet. Use Worksheet No. 2 during the presentation to take notes on the function of the transmission control valve components. During the lab exercise, fill in the blanks with the correct letter from the g raphic and write the function for each component.
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Lab A: Power Train Hydraulic System Component Identification Worksheet No. 1 Directions: Use this worksheet during the presentation to take n otes on the location and function of each component. During the lab exercise, match the tag attached to the component with the correct name. Tag No.
___
Component
Transmission Pump Suction Screen Location: Function:
___
Transmission Pump Location: Function:
___
Transmission Oil Filter Location: Function:
___
Transmission Control Lever Location: Function:
___
Torque Converter Location: Function:
___
Transmission Location: Function:
___
Transfer Gear Location: Function:
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Lab A: Power Train Hydraulic System Component Identification Worksheet No. 1 (continued)
Tag No.
___
Component
Drive Shafts (6) Location: Function:
___
Final Drives (3) Location: Function:
___
Differential and Bevel Gear Cases (3) Location: Function:
___
Transmission Actual Gear Switch Location: Function:
___
Transmission Oil Cooler Location: Function:
___
Transmission/Chassis ECM Location: Function:
___
Transmission Oil Filter Bypass Valve Location: Function:
___
Solenoid and Relief Valve Group Location: Function:
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Lab A: Power Train Hydraulic System Component Identification Worksheet No. 1 (continued)
Tag No.
Component
___
Transfer Gear Pump Location: Function:
___
Transfer Gear Oil Filter Location: Function:
___
Transfer Gear Magnetic Screen Location: Function:
___
Upshift Solenoid Location: Function:
___
Downshift Solenoid Location: Function:
___
Torque Converter Lockup Clutch Solenoid Location: Function:
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Student Materials
Lab A: Power Train Hydraulic System Component Identification Worksheet No. 2 Directions: Use this worksheet during the presentation to take n otes on the function of the transmission control valve components. During the lab exercise, use the illustrations on the next page and fill in the blanks with the correct letter for each component.
Pressure Control Valve Function:
Selector and Pressure Control Valve Function:
Torque Converter Lockup Clutch Modulating Valve Function:
Rotary Actuator Function:
Torque Converter Inlet Relief Valve Function:
Pilot Pressure Test Location Function:
Load Piston Body (Station A) Function:
Load Piston Body (Station B) Function:
Load Piston Body (Station C) Function:
Load Piston Body (Station E) Function:
Load Piston Body (Station F) Function:
Load Piston Body (Station G) Function:
Load Piston Body (Station H) Function:
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Student Materials
Lab A: Power Train Hydraulic System Component Identification Worksheet No. 2 (continued)
H
G
C
D
B
A
K
J
E
F
M
G I
M
L
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Student Materials
Lab B: Power Train Hydraulic System Testing and Adjusting BACKGROUND INFORMATION
INDIVIDUAL EXERCISE
This lab measures your ability to perform various testing and adjusting procedures on 740 Articulated Truck Power Train Hydraulic System.
Using the procedures in the 740 Articulated Truck Systems Operation, Testing and Adjusting module (Form RENR5134) and the Lab B Handout, locate the power train hydraulic system test point locations and specifications and record on the Lab B Worksheets.
GROUP EXERCISE
Demonstrate the power train hydraulic system pressure tests using the procedures in the 740 Articulated Truck Systems Operation, Testing and Adjusting module (Form RENR5134) and record the results on the Lab B Worksheets.
MATERIALS NEEDED
______Class notes ______Lab B Worksheets ______Lab B Handout ______740 Power Train Systems Operation, Testing and Adjusting Service Manual module (Form RENR5134) ______740 Articulated Truck ______Mechanic's tools ______1U5481 Pressure Gauge Group ______1U5482 Pressure Adapter Group (for 1U5481) ______8T5200 Generator and Counter Signal Group ______FT2796 Connector Harness ______6V6064 Transmission Test Cover
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Student Materials
Lab B: Transmission Hydraulic System Pressure Tests Worksheet Machine Model________________________
Date_____________________
Serial Number_________________________
S.M.H.___________________
VISUAL CHECKS:
Oil level______________
Oil leaks?____________
Air/water in oil?____________
Pressure Tests
TEST POINT
TEST Pilot Torque Converter Lockup Clutch
Low Initial Idle Max
Torque Converter Inlet Relief Valve
High Idle
Transmission Pump
High Idle
Low Idle
Low Idle
Transmission Pilot Pressure Upshift Pressure Downshift Pressure Transmission Lube
High Idle Low Idle
SPECIFICATIONS
ACTUAL
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Student Materials
Lab B: Transmission Hydraulic System Pressure Tests Worksheet (continued)
740 TRUCK CLUTCH CHART CLUTCHES SPEED ENGAGED
INITIAL CLUTCH PRESSURE Load Piston Plug Removed STATION
CLUTCH
R
1
A
3
N
3 and 7
B
1
1
2 and 6
C
2
2
1 and 6
E
5
3
3 and 6
F
4
4
1 and 5
G
6
5
3 and 5
H
7
6
1 and 4
7
3 and 4
SPECS CLUTCH
A
3
B
1
C
2
E
5
F
4
G
6
H
7
ACTUAL
MAXIMUM CLUTCH PRESSURE Load Piston Plug Installed
740 TRUCK CLUTCH CHART
STATION
SPECS
LOW IDLE
HIGH IDLE
ACTUAL LOW IDLE
HIGH IDLE
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Lab B: Transmission Shift Points Worksheet
MODIFIED SHIFT POINTS AT NOMINAL ENGINE SPEED UPSHIFT
SPEC
ACTUAL
SPEC
ACTUAL
1C to 1L 1 to 2 2 to 3 3 to 4 4 to 5 5 to 6 6 to 7 DOWNSHIFT 7 to 6 6 to 5 5 to 4 4 to 3 3 to 2 2 to 1 1L to 1T
SHIFT POINT AT NOMINAL ENGINE SPEED UPSHIFT
SPEC
ACTUAL
SPEC
ACTUAL
1C to 1L 1 to 2 2 to 3 3 to 4 4 to 5 5 to 6 6 to 7 DOWNSHIFT 7 to 6 6 to 5 5 to 4 4 to 3 3 to 2 2 to 1 1L to 1T
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Student Materials
Lab B: Transfer Gear Hydraulic System Pressure Tests Worksheet
TEST POINT
TEST Transfer Gear Lubrication Pressure Low Idle
Axle Differential Locks
13
Supply
13
Front Axle
15
Center Axle
17
Rear Axle
16
SPECIFICATIONS
ACTUAL
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Lab B: Transmission Hydraulic System Testing Locations Handout
E
A B
8
F
G
C D
Clutch pressures
8. Transmission pilot pressure A. B. C. D.
Clutch No. 3 Clutch No. 1 Clutch No. 2 Lockup clutch
1 10
11
1. 7. 10. 11.
H
7
Torque converter lockup clutch pilot pressure Transmission pump pressure Upshift pressure Downshift pressure
E. F. G. H
Clutch No. 5 Clutch No. 4 Clutch No. 6 Clutch No. 7
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Lab B: Transmission Hydraulic System Testing Locations Handout (continued)
12
6
6. Torque converter inlet relief pressure 12. Transmission lubrication pressure
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Lab B: Transfer Gear Hydraulic System Testing Locations Handout
13
15
13. Transfer gear lubrication pressure
15. Front axle differential lock test point
17 16
16. Rear axle differential lock test point
17. Center axle differential lock test point
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Student Materials
Lab C: Torque Converter Stall Test BACKGROUND INFORMATION
MATERIALS NEEDED
This lab measures your ability to perform torque converter stall test on the 740 Articulated Truck Power Train Hydraulic System.
______Lab C Worksheet ______740 Articulated Truck ______725/730/735/740 Articulated Trucks Power Train Electronic Control Systems Operation, Troubleshooting, Testing and Adjusting module (Form RENR3442).
INDIVIDUAL OR GROUP EXERCISE
Following the procedures in the 725/730/735/740 Articulated Trucks Power Train Electronic Control Systems Operation, Troubleshooting, Testing and Adjusting module (Form RENR3442), perform the torque converter stall test procedure using the Caterpillar Monitoring System. Answer the worksheet questions after completing the test procedure.
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Lab C: Torque Converter Stall Test Worksheet 1. What Caterpillar Monitoring System submode is used to perform the Torque Converter Stall test?
2. What does "Sc E08" indicate on the Caterpillar Monitoring System, if displayed during the Torque Converter Stall test?
3 If no errors are detected during the Torque Converter Stall test, what value will the Caterpillar Monitoring System display?
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Student Materials
740 Articulated Truck Power Train Hydraulic System Case Study DIRECTIONS
You may use the service manual and class notes to complete the exercise. Answer the questions on the Case Study Worksheet. Discuss the exercise with the instructor after you have answered the case study questions. The following case study is based on a possible field complaint.
SITUATION
The operator of a 740 Articulated Truck reported to his supervisor that the transmission was slipping in third and fifth gear. He told the supervisor that the problem had been present for a couple of days.
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Student Materials
Power Train Hydraulic System Troubleshooting Worksheet ISOLATE PROBLEM Gather Information
Verify
Perform Visual Inspection
State Problem
The first step in in a troubleshooting process is to gather information before starting any work on the machine. If possible talk to the operator. Also, check the repair history of the machine and the Caterpillar Service Information System (SIS). List at list three questions you would ask an operator to help in identifying that a problem exists. Possible answers:
Verify the problem exists. Operate the machine to duplicate the problem, preferably under similar operating conditions. Compare the operation to a known good machine. Perform sensory checks such as looking, listening, touching, and smelling to verify a problem exists.
When troubleshooting always perform a visual inspection first. Look for the obvious. List at least three typical items that should be inspected during a visual inspection. Possible answers:
After verifying a problem exists, state in your own words what the problem is. Caution: Do not identify the solution. Possible answer:
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Power Train Hydraulic System Troubleshooting Worksheet (continued) LIST POSSIBLE FAULTS
The next step in the process is to list all of the possible causes of the problem. Identify all systems and components that could be causing the problem, including the least obvious. List at least three things that could be causing the problem. Possible answers:
Devise tests and determine root cause
Now, create a list of tests that should be performed and describe what the tests would determine. Prioritize the tests as to which sequence they should be performed in. As a general rule, always do the easiest tests first. Also, list diagnostic tooling required. Identify at least four tests to perform. (NOTE: the rankings are only suggested.)
Tooling needed:
Tooling needed:
Tooling needed:
Tooling needed:
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Power Train Hydraulic System Troubleshooting Worksheet (continued)
Tooling needed:
REPAIR FAULT
After isolating the component, which you suspect from your test results is causing the problem, either adjust or replace the component.
Circle the best response:
If the modulating valve initial pressure is too low and the load piston spring rates are correct what step would you perform next? 1. Add shims behind the load piston spring 2. Remove shims from behind the load piston spring 3. Turn the load piston adjustment screw clockwise 4. Turn the load piston adjustment screw counterclockwise
VERIFY REPAIR
After completing the repair, always verify the machine is operating correctly. List at least three things you would do to make sure the repair was done correctly. 1. 2. 3. 4. Complete the service report after finishing the job.
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Student Materials
740 Articulated Truck Power Train System Components and Functions Posttest BACKGROUND INFORMATION
Course materials and class notes may be used when taking the posttest. Do not consult with others during the posttest.
MATERIALS NEEDED
EXERCISE
______740 Articulated Truck Power Train System Components and Functions Posttest
Follow the instructions on the posttest.
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Student Materials
735 Articulated Truck Power Train System Components and Functions Posttest
Directions: Match the component with the function by placing the letter next to the component.
1. Transmission Oil Filter Bypass Valve
2. Rotary Actuator
A. Controls transmission hydraulic system pressure B. Controls oil flow to the transmission clutches
3. Torque Converter Lockup Clutch Solenoid Valve
C. Opens when the transmission oil filter is plugged and allows oil from the pump to bypass the filter
4. Torque Converter Inlet Relief Valve
D. Directs oil from the transfer gear pump to the transfer gear and the axle differentials
5. Pressure Control Valve
E. Controls the modulation of lockup clutch engagement F. Controls the position of the selector spool
6. Solenoid and Relief Valve Group
7. Selector and Pressure Control Valve
8. Upshift Solenoid
G. Ensures sufficient oil pressure in the torque converter H. Directs oil to the rotary actuator
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Student Materials
740 Articulated Truck Selector and Pressure Control Valve Component Identification Posttest BACKGROUND INFORMATION
Course materials and class notes may be used when taking the posttest. Do not consult with others during the posttest.
MATERIALS NEEDED
EXERCISE
______740 Articulated Truck Selector and Pressure Control Valve Component Identification Posttest
Identify the Selector and Pressure Control Valve components by listing the letter designation of the components next to the appropriate component names on the posttest.
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Student Materials
740 Articulated Truck Selector and Pressure Control Valve Component Identification Posttest
740 TRANSMISSION SELECTOR VALVE GROUP NEUTRAL A B
C
D
E
F
Directions: Fill in the blanks next to the terms with the correct letter.
Main relief valve Rotary selector spool Priority reduction valve Torque converter inlet relief valve Neutralizer valve Pilot oil pressure tap Lubrication pressure tap
G
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Student Materials
740 Articulated Truck Pressure Control Valve Operation Posttest BACKGROUND INFORMATION
Course materials and class notes may be used when taking the posttest. Do not consult with others during the posttest.
MATERIALS NEEDED
EXERCISE
______740 Articulated Truck Pressure Control Valve Operation Posttest
Follow the instructions on the posttest.
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Student Materials
740 Articulated Truck Pressure Control Valve Operation Posttest Directions: Multiple Choice. Refer to the pressure control valve station graphic to answer the following questions. Circle the correct letter(s) indicating the best answer(s) for each question. TRANSMISSION PLANETARY VALVE STATION 1
2
3
4
5
10
9
6 7
1. When a shift is started, pilot oil from the rotary selector spool flows through which passage. A. 1 B 2 C. 3 D. 8 2. When the clutch begins to fill, the oil pressure in the clutch is balanced against ____________________. A. Pilot pressure at the load piston (4) B. Force of spring (9) C. Force of springs (5) D. Slug (10) 3. The force of springs (5) and ___________________ control the amount of time for the clutch to reach maximum pressure. A. Pilot pressure B. Pump pressure C. Force of spring (9) D. Size of the load piston orifice (7) 4. What controls the amount of time necessary for the clutch to release? A. Force of springs (5) B. Decay orifice (6) C. Force of spring (9) D. Load piston orifice (7)
