Equipos 793 gy 1 01, 2010 pagos KENR8392 September 2009 Systems Operation 793F Off-Highway ruck Power Train SSPI -Up (Machine) SAFETY. CAT. COM i03684547 Important Safety Information Most accidents that involve product operation, maintenance and repair are caused by failure to observe basic safety rules or precautions. An accident can often be avaided by recognizing potentially hazardou cident occurs. A oro person must be alert p % is person should S»ipe also have the necess nd Ols to perform these functions properly.
I ation, maintenance or repair of this prod d could result in injury or death. Do not operate or perform any lubrication, maintenance or repair on this product, until you have read and understood the operation, lubrication, maintenance and repair information. Safety precautions and warnings are provided in this manual and on the product. Ifthese hazard warnings are not heeded, bodily injury or death could occur to you or to other persons. The hazards are identified by the «Safety Alert Symbol» and fonowed by a «Signal Word» such as «DANGER», ‘WARNING» or «‘CAUTION».
The Safety Alert «WARNING» label is shown below. The meaning of this safety alert symbol is as follows: Attention! Become Alert! Your Safety is Involved. The message that appears under the warnlng explains the hazard and can be either written or pictonally presented. A non-exhaustive list of operations that «NOTICE» labels on the product and in this publication. Caterpillar cannot anticipate every possble circumstance that might involve a potential hazard. The warnings in this publication and on the product are, therefore, not all inclusive.
You must not use this product in any manner different from that considered by this manual without first satisfying yourself that you have considered all safety rules and precautions applicable to the operation of he product in the location of use, including site-specific rules and precautions applicable to the worksite. If a tool, procedure, work method or operating technique that is not specifically recommended by Caterpillar is used, you must satisfy yourself that it is safe for you and for others.
You should also ensure that the product WII not be damaged or became unsafe by the operation, lubrication, maintenance or repair procedures that you intend to use. The information, specifications, and illustrations in this publication are on the basis of information that was available t the time that the publication was written. The specifications, torques, pressures, measurements, adjustments, illustrations, and other items can change at any time. These changes can affect the service that is given to the product. Obtain the complete and most current informaticn before you start any job.
Caterpillar dealers have the most current information available. When replacement parts are required for this product Caterpillar recommends using Caterpillar replacement parts or parts with equivalent specifications including, but not limited to, physical dimensions, type, strength and materi OF dimensions, type, strength and material. Failure to heed this warning can lead to premature failures, product damage, personal injury or death. In the Unlted States, the maintenance, replacement, or repair of the emission control devices and systems may be performed by any repair establishment or individual of the owner’s choosing.
KENR8392 3 Table of Contents Table of Contents Systems Operation Section General Information Electronic Control Module (Power Train) Transmission Control Speedometer/Tachometer Module (Transmission Gear Indicator) Position Sensor (Hoist Control) Sensor (Dump Body) . Speed Sensor Modulating Valve (Transmisslon (Transmission) . Hydraulic Control) Modulating Valve (Torque Converter Lockup Clutch) . Torque Converter Sump . Gear Pump (Torque Converter and Transmission) Magnetic Screen (Transmission) Oil Filter (Torque Converter) „ 011 Filter (Transmission Charging) . Screen (Torque . Oil Cooler (Torque Converter Converter) .
Screen (Torque Converter) 011 Cooler (Torque Converter and Transmission) „ Torque Converter Inlet and Outlet ReliefValves Torque Converter Transfer Gears — Transmission Hydraulic Control . Lubrication Relief Valve (Transmission) Transmission Planetary Pump . . Rear Axle and D nve • • • • • • • • • • • Final Drive System Gear Pump (Rear Mie Oil) . . . Oil Filter (Rear Axle Lubrication) Temperature Sensor (Rear Axle 011) — Flow Control and Relief Valve (Rear Axle Differential and Bevel Gear Oil) Final Drive . 4610111 112121415 16 16 18 18 19 19 20 20 21 25 26 27 28 35 37 38 3940 40 4244 Index Section Index . 5 4 Systems Operation Section i03605641 SMCS code: 3000; 3100; 4000 Illustration 1 Basic diagram for the power train systems gol 930555 The power train is made u systems. The following ystems are the four syste Gears and Transmission • Differential and Final Drives The four basic systems have a hydraulic connection, an electrical connection, a magnetic connection, or a mechanical connection. 5 Systems Operation Section The chassis electronic control module (chassis ECM) matches the transmission Speed to the selected Speed of the transmission shift lever.
The chassis ECM gets information of the selected Speed of operation through the electrical system. The chassis ECM activates the transmission hydraulic system and the torque converter hydraulic systems through the modulating valve olenoids for the transmission, and the modulating Valve solenoid for the torque converter lockup clutch. The torque converter has a lockup clutch for direct drive and a one-way clutch for torque converter drive. The torque converter is fastened directly to the flw•heel ofthe engine. The torque converter drives the transmission hydraulically, unless the lockup clutch is activated.
When the lockup solenoid is activated, the lockup clutch is hydraulically engaged. The torque converter rotating housing is novv mechanically connected to the output shaft of the torque converter. The drive shaft mechanically connects the torque onverter to the transfer gears. The transfer gears are fastened directly to the transmission. The modulating valve solenoids for the transmission hydraulically activate the transmission hydraulic control valves. The control valves activate the transmission clutches which cause the mechanical connection to the transmission output shaft.
The clutches in the transmisslon Will not drive the transmission s OF to the transmission output shaft. The clutches in the transmission Will not drive the transmission output shaft unless the torque converter is activated hydraulically or the torque converter is ctivated mechanically. The transmission has seven forward speeds and one reverse speed. The selection of Speed is done manually in REVERSE, in NEUTRAL and in FIRST. The selection of SECOND through SIXTH speeds is done automatically. Power is sent through the REVERSE gear in torque converter drive only. FIRST has both a torque converter drive and a direct drive.
SECOND through SIXTH speeds are direct drive only with a very short time of converter drive during transmission clutch engagement in order to enable smoother shifts. The transmission is fastened directly to the differential and bevel gear. The differential and bevel gear are fastened directly to the rear axle housing_ After the transmission is connected to the torque converter, power flows from the engine through the torque converter and the transmission to the differential. The rear axles mechanically connect the differential to the final drives. The final drives are connected to the rear wheels. Power is then sent to the tires. 03604701 SMCS code: 31 68; 4020; 4800 Illustration 2 g00527172 The Power Train Electronic ule (Power Train ECM) is the main component in th electrical system. The Power Train ECM has several input signals and output signals. Refer to Illustration 2 for the Input signals and the output signals. The Power Train ECM receives current through a fuse on the fuse block. This current is used to activate the modulating Valve (torque converter lockup clutch), and the modulating valve (transmission hydraulic control). These modulating valves control the option of torque converter drive or the option of direct drive.
These modulating valves also control the direction and the Speed The Power Train ECM also controls the electrical system for the hoist. Illustration 3 Location of the Power Train Electronic Control Module gol 929798 Systems Operation Section The Cat Data Link is used to share information with other systems such as the Brake Electronic Control Module (Brake ECM), the Engine Electronic Control Module (Engine ECM), and the Advisor panel. Signals that are sent to the Engine ECM result in reduced engine Speed during upshifts and increased engine Speed during downshifts.
The grake ECM controls the following items: System Operation Table 1 Operation of the Torque Converter For Transrmssion Speed Transmission Speed Torque Converter Drive Direct Drive with an Engaged Lockup Clutch • Traction Control System etarder Control • Rear axle ooling Body up gear limit • Protection for starter • Body hoist control • Speed limiter • Shift control • Neutral start • Backup alarm • Overspeed protection • Controlled Throttle Shift (CTS) • Engine prelube • Directlonal shift management • Autolube Neutral (Torque Converter Drive) With the shift lever switch in the NEUTRAL position, current flows from the Chassis ECM through the shift lever switch to machine ground.
The Chassis ECM then sends a signal to the Transmission ECM. The Transmission ECM uses this signal in arder to deactivate the supply solenoids for the transmission clutches. This keeps the transmission in the NEUTRAL position. Note: The second transmission clutch remains engaged while the transmission is in the NEUTRAL position. First (Torque Converter Drive or Direct Drive) When the transmission control is moved to the FIRST position, the shift lever switch moves to the FIRST position. Current then flows from the Chassis ECM through the shift lever switch to machine ground. The Chassis ECM analyzes this signal in order to understand that the shift lever switch is in FIRST position.
The Chassis ECM sends a command for the position of the shlft lever to the Transmission ECM. The Transmission ECM then sends a calibrated current to the correct supply solenoids for the transmission clutches. The transmission clutches for FIRST gear are novv engaged. The machine is now in FIRST gear and the machine is in torque converter drive. 8 Systems Operation Section FIRST gear is torque converter drive at Iower ground speeds. First gear is direct drive at higher ground speed. There are two t drive at Iower ground speeds. First gear is direct drive at higher ground speed. There are two transmission Speed sensors that transmit a signal to the Transmission ECM.
There is also a torque onverter output Speed sensor that transmits a signal to the Transmission ECM. When the Transmission ECM is receiving a valid signal from of these three sensors, the Transmission ECM Will allow the transmission to shift. These signals tell the Transmission ECM the ground Speed ofthe machine. When the ground Speed reaches approximately 6 km/h (4 mph), the Transmission ECM sends a calibrated current to the lockup clutch solenoid. When the lockup clutch solenoid is activated, hydraulic oil pressure goes to the lockup clutch. The machine is in FIRST gear and the machine is in direct drive. The lockup clutch Will stay activated until there is an upshift, a downshift, or a decrease in ground speed.
If there is a suficient decrease in ground Speed and the machine is Still in FIRST, the Transmission ECM Will stop current to the lockup solenoid. The lockup solenoid Will deactivate. Hydraulic oil pressure to the lockup clutch Will stop and the machine Will return to torque converter drive. The Power Train ECM determines that FOURTH gear is needed. When the transmission gear swltch is in the FOI_JRTH position, current flows from the Power Train ECM through the transmission ear switch to machine ground. The Power Train ECM determines that the shift is complete. The machine is now in FOURTH gear and the machine is in direct drive. Shifting Procedures The following sections Will explain the operations of automatic upshi upshifts and downshifts.
Except for different electrical wires that must be grounded or activated, the shifting sequence is basically identical for all speeds. Typical Automatic Upshift (SECOND to THIRD) When the transmission control is put in THIRD Speed position, the shift lever switch is turned to the THIRD Speed position. Current goes from the Chassis ECM through the shift lever switch to machine ground. The Chassis ECM analyzes this signal in arder to understand that the shift lever switch is in the THIRD Speed position. The Chassis ECM sends a command for the position of the shift lever to the Transmission ECM. The command for the shlft lever switch and a Slgnal from the Speed sensors for the torque converter and for the transmission Will inform the Transmission ECM that an upshift is needed.
The upshift to THIRD Speed position from SECOND Speed position is automatic when the correct ground Speed signal from the Speed sensors for the torque converter and for the transmission is sent to the Transmission ECM. Aso, the transmission control must be in THIRD Speed position or above THIRD Speed position. The Transmission ECM stops current flow to the lockup clutch solenoid when a shift is necessary. The lockup clutch solenoid deactivates. Hydraulic oil to the lockup clutch stops and the machine is in torque converter drive for a moment. Aso, the Transmission ECM stops current flow to the two supply solenoids for the transmission clutches that are engaged. Hydraulic oil to the transmission clutches stops and the clutches 63