TRANSMISION D6D

Cerrar SIS

Pantalla anterior

Producto: TRACK-TYPE TRACTOR

Modelo: D6D TRACK-TYPE TRACTOR 9FK

Configuracin: D6D TRACTOR / POWER SHIFT / 9FK00001-UP (MACHINE) POWERED BY 3306 ENGINE

Operacin de SistemasD6D TRACTOR POWER TRAIN

Nmero de medio-SENR7439-00 Fecha de publicacin -01/05/1977 Fecha de actualizacin -12/10/2001

Systems Operation

Pgina 1 de 72D6D TRACTOR / POWER SHIFT / 9FK00001-UP (MACHINE) POWERED BY 330...

11/06/2012https://sis.cat.com/sisweb/sisweb/techdoc/techdoc_print_page.jsp?returnurl=/sisweb/sisw...

General Information - (Power Shift)

LOCATION OF COMPONENTS

1. Transmission hydraulic controls. 2. Universal joint. 3. Diesel engine. 4. Steering clutches. 5. Final drive. 6. Range

transmission. 7. Torque divider.

Power from diesel engine (3) is sent through the engine flywheel and torque divider (7) to universal joint (2). The universal joint drives sun gears and planet gears in the transmission.

Five planetary gear trains, each with its own clutch, give the tractor three speeds in either FORWARD or REVERSE. The selection of the desired tractor speed is done manually by the operator but hydraulic oil, directed by the transmission hydraulic controls (1), engages the clutches in the transmission.

A bevel pinion in the transmission group, sends power from transmission (6) to the bevel gear. Thepower is sent through steering clutches (4) into final drives (5), to the sprockets which drive the tracks.



The steering clutch and bevel gear case houses the bevel gear, steering clutches and brakes.

The steering clutches are used to turn the tractor. The brakes are used to stop the tractor and giveassistance to the action of the steering clutches.

General Information - (Direct Drive)

LOCATION OF COMPONENTS

1. Transmission. 2. Flywheel clutch. 3. Diesel engine. 4. Steering clutch. 5. Final drive. 6. Universal joint.

Power from diesel engine (3) is sent from the engine to flywheel clutch (2). The flywheel clutch is engaged and disengaged manually. The output shaft of the flywheel clutch drives the upper shaft in transmission (1) through a universal joint (6).

The transmission has five FORWARD and four REVERSE speeds. The selection of these speeds is done manually. The bevel pinion, at the rear of the transmission, sends the power to the bevel gear. The power is then sent through steering clutches (4) into final drives (5), to the sprockets which drive the tracks.



The steering clutch and bevel gear case houses the bevel gear, steering clutches and brakes.

The steering clutches are used to turn the tractor. The brakes are used to stop the tractor and give assistance to the action of the steering clutches.

Hydraulic System - (Power Shift)

TRANSMISSION AND STEERING CLUTCH OIL SYSTEM SCHEMATIC (POWER SHIFT)

1. Hydraulic control mechanism for left brake.

2. Hydraulic control valve for the steering clutches and brakes.

3. Oil filter.

4. Vent line from pump.

5. Oil pump.

6. Magnetic screen.

7. Oil cooler (air to oil).

8. Pressure control valve.

9. Relief valve for torque converter outlet.

10. Hydraulic control mechanism for right brake.



11. Temperature bypass valve.

12. Transmission.

13. Reservoir in steering clutch and bevel gear case.

14. Transmission lubrication relief valve.

15. Pressure relief valve.

16. Scavenge pump.

17. Relief valve for torque converter inlet.

18. Torque converter housing.

19. Oil cooler (oil to water).

Introduction

The hydraulic system has a common reservoir. It gives lubrication oil for the bevel gear and pinion, transmission and torque divider. It also gives cooling oil for the torque converter, steering clutches and brakes. Pressure oil from the oil pump is for operation of the hydraulic controls for the steering clutches and brakes, the hydraulic controls of the transmission and the torque converter.

Operation

Oil is pulled from reservoir (13) through magnetic screen (6) by oil pump (5). Vent line (4) goes from pump (5) and makes a connection with a line from inlet relief valve (9) for the torque converter. When the engine is first started, this line lets any air in the suction section of the pump go out of the pump. The operation of the pump starts faster. After the engine is running, this oil line lets a specific amount of oil go to the torque converter.

Pump (5) sends pressure oil to oil filter (3). The oil goes through the filter. If the oil filter element has restrictions, a bypass valve in the filter lets the oil go around the filter.

From the filter the oil goes to pressure relief valve (14), to hydraulic control valve (2) for the steering clutches and brakes. This oil is used for the operation of the steering clutches and hydraulic control mechanisms (1) and (1) for the brakes.

A small amount of oil goes from control valve (2) through an orifice. This oil is for the lubrication of the control valve, bevel gear and the bearings for the bevel gear shaft.

The oil to pressure control valve (8) is for the clutches of the transmission.

Pressure relief valve (15) prevents the pressure in the system from going over approximately 375 psi (2600 kPa). If the pressure in the systems gets too high, the relief valve opens and lets the extra oil go to inlet relief valve (17) for the torque converter. An orifice in the body of pressure relief valve (15) lets oil go to the inlet relief valve for the torque converter at all times.

Inlet relief valve (17) for the torque converter controls the inlet pressure to the torque converter. Leakage of oil inside the torque converter is for lubrication of the torque divider components. After lubrication of the components, the oil goes to the bottom of torque converter housing (18).



Scavenge pump (16) takes the oil from the torque converter housing. The pump sends the oil to the reservoir in the transmission case. From there, the oil goes to reservoir (13) in the differential and bevel gear case.

Outlet oil from the torque converter goes to outlet relief valve (9) for the torque converter. The outlet relief valve controls the pressure inside the torque converter. From the outlet relief valve the oil goes to temperature bypass valve (11).

Temperature bypass valve (11) controls the amount of oil that is sent through air-cooled oil cooler (7). When the temperature of the oil from the outlet relief valve reaches 135F (57C), the temperature bypass valve starts to close. This directs some of the oil through oil cooler (7) before it goes through oil cooler (19). When the temperature of the oil increases to a temperature of 170F (77C), bypass valve (11) will be completely closed, which forces the flow of oil through oil cooler (7) before itpasses through oil cooler (19).

After the oil is cooled, it goes to lubrication relief valve (14).

After the lubrication relief valve, the oil is sent to the front and rear of the transmission for component lubrication.

Hydraulic Pump

The location of the hydraulic pump is on the left rear face of the flywheel housing. It is a single section gear-type pump driven by the engine flywheel.



COMPONENTS OF HYDRAULIC PUMP

1. Manifold assembly. 2. Body assembly. 3. Cover assembly. 4. O-ring seals. 5. Drive gear. 6. Bearings. 7. Lip-type seal.

8. Idler gear. 9. Passage. 10. Bearings.

Drive gear (5) has splines and is driven by a gear in the flywheel housing. Gear (5) turns idler gear (8). During operation, oil from the steering clutch and bevel gear case goes into the lower part of the pump through manifold assembly (1). The oil is then sent through a passage to the lower part of body assembly (2). The oil fills the space between the gear teeth. The gears turn, and the oil is sent outpassage (9) of manifold assembly (1) to provide pressure oil to the hydraulic system.

When the engine is not running, air is present in the pump. When the engine is started, air that is with the oil is sent from the pump through a line to the torque converter. This keeps the air out of the oil that is sent to the hydraulic system.

Magnetic Screen

The location of the magnetic screen is between the reservoir in the steering clutch and bevel gear case and the inlet to the hydraulic oil pump.

MAGNETIC SCREEN CONSTRUCTION

1. O-ring seal. 2. Cover. 3. Wave washer. 4. Housing. 5. Outlet. 6. Magnets. 7. Screen. 8. Tube assembly. 9. O-ring sea.

Oil from the reservoir comes into the magnetic screen through the bottom. As the oil flows through tube assembly (8) toward the top, it passes through the openings between magnets (6). The magnets are installed on the tube assembly so that the same magnetic ends are next to each other. As the oil



goes over the magnets, metal particles are stopped and held by the magnets. These magnets will not let the metal particles go with the oil through the hydraulic system.

The oil then goes through screen (7) on its way to outlet (5). As the oil goes through the screen, other foreign particles are stopped and can not go into the hydraulic system.

From outlet (5), the oil is sent to the inlet port of the hydraulic oil pump.

Oil Filter

Pressure oil from the hydraulic oil pump goes in filter housing (11) through an inlet passage near the top of the housing. Oil fills the space between filter element (7) and the inside wall of housing (11). During normal operation, the oil goes through element (7) and then goes out the bottom of the filter housing through an outlet tube. As the oil goes through the filter element, foreign particles are stopped and can not go through the hydraulic system.

If filter element (7) becomes full of debris (clogged), oil can not go through. At this time, pressure oil moves bypass valve (4) against the force of its spring and the valve will open. This lets the oil flow out the bottom of the filter housing through the outlet tube without restriction.

OIL FILTER CONSTRUCTION

1. Cover assembly. 2. Bolts. 3. O-ring seal. 4. Bypass valve. 5. Spring. 6. Washers. 7. Filter element. 8. Retainer. 9. Seal.

10. Spring. 11. Filter housing. 12. Plug.

Since the oil that goes through bypass valve (4) is not cleaned of debris, damage to other components in the hydraulic system will result.



Correct maintenance should be used to make sure that the filter element does not become full of debris and stop the flow of clean oil to the hydraulic oil system.

Transmission Oil Coolers

Transmission and hydraulic system oil is sent to the temperature bypass valve from the relief valve for the torque converter outlet. At this point, the oil is either sent through one or two oil coolers, according to the temperature of the oil. If the temperature of the oil is below 135F (57C), the bypass valve directs the oil through a water-cooled oil cooler. The water-cooled oil cooler uses coolant fromthe engines cooling system to take the heat away from the hydraulic oil.

TRANSMISSION OIL COOLER (SCHEMATIC)

1. Oil cooler.

Coolant from the engine comes in at the front end. The coolant goes through the many long tubes that are in the cooler. After the coolant goes through the tubes, it goes out through the other end of the cooler and returns to the engine cylinder block.

If the temperature of the oil increases to a temperature above 135F (57C), the bypass valve will begin to close and cause some of the oil to go through a second cooler. The second oil cooler is a air-cooled oil cooler. The air-cooled oil cooler uses air that goes through the fins of the cooler to remove the heat from the oil. After the oil leaves the air-cooled oil cooler, it is sent through the water-cooled oil cooler. When the temperature of the oil gets to 170F (77C), the bypass valves will be completely closed. This will cause all the oil from the relief valve for the torque converter outlet to go through both the air-cooled and water-cooled oil coolers. After the oil is cooled, it goes to the transmission lubrication relief valve, where it is sent to the front and rear of the transmission for lubrication of components.



Transmission Hydraulic Controls - (PowerShift)

HYDRAULIC CONTROLS (FIRST SPEED REVERSE)

1. Torque converter.

2. Body of relief valve for converter outlet.

3. Relief valve for converter outlet.


5. Water-cooled oil cooler.

6. Lubrication line to front of transmission.

7. Air-cooled oil cooler.

8. Lubrication relief valve.

9. Lubrication line to rear of transmission.



10. Scavenge oil pump.

11. Oil reservoir for torque converter.

12. Hydraulic controls for steering clutches and brakes.

13. Load piston.

14. Body of pressure control valve.

15. Check valve.

16. Flow control orifice.

17. Relief valve for converter inlet.

18. Body of sequence relief valve.

19. Modulating valve.

20. Pressure differential and safety valve.


22. Oil filter.

23. Bleed line for oil pump.

24. Body of selector valve.

25. Spool for direction selection.

26. Oil reservoir.

27. Magnetic screen.

28. Transmission oil pump.

29. Spool for speed selection.

A. Pressure tap for converter outlet.

B. Pressure tap for lubrication.

C. Pressure tap for converter inlet.

D. Pressure tap for sequence relief valve.

E. Pressure tap for speed clutches.

F. Pressure tap for direction clutches.

G. Pressure tap for transmission oil pump.



HYDRAULIC CONTROLS (FIRST SPEED FORWARD)













13. Load piston.




15. Check valve.







22. Oil filter.




26. Oil reservoir.













HYDRAULIC CONTROLS (NEUTRAL, ENGINE NOT RUNNING)















13. Load piston.


15. Check valve.







22. Oil filter.




26. Oil reservoir.











The transmission hydraulic controls are made up of a pump, filter, control valves, a selector lever and a linkage mechanism. The hydraulic controls send oil to the clutches in the transmission. Oil not used by the clutches is sent through pressure relief valve (21) to inlet relief valve (17) for the torque converter.



The location of transmission oil pump (28) is on the left rear face of the flywheel housing. The pump is driven by the engine flywheel. The pump pulls the oil from reservoir (26) and sends it to filter (22) on the left side of the engine. From the filter, the oil goes to pressure relief valve (21) on the torque divider housing and to the hydraulic controls (12) for the steering clutches. Relief valve (21) keeps the pressure of the oil to the hydraulic controls at approximately 375 psi (2600 kPa) maximum. The oil from relief valve (21) goes to pressure control valve body (14). The extra oil goes to the inlet relief valve (17) for the torque converter.

The pressure control valve is made up of two valves: modulating valve (19) and pressure differentialand safety valve (20). The modulating valve prevents sudden clutch engagement. The pressure differential valve keeps a difference in the pressure between the speed clutch and direction clutch. Both valves work in combination to engage a speed clutch before a direction clutch is engaged. This arrangement gives smooth engagement of the transmission and lets most of the load to be taken up by the direction clutches. The safety valve keeps the transmission from engaging when the engine is started with the transmission in a speed position.

Oil, at speed clutch pressure, goes from the pressure control valve body (14) through a passage to selector valve body (24). The oil goes through the selector valve body to speed selection spool (29). The speed selection spool is in a position to send oil to one of the three speed clutches. The speed selection spool is connected by linkage to the selection lever of the transmission. The position ofspeed selection spool (29) is controlled by the position of the selection lever.

Oil, at direction clutch pressure, goes through a passage in pressure control body (14) to selector valve body (24). The oil goes through the selector valve body to direction selection spool (25). The direction selection spool is in a position to send oil to one of the two direction clutches. The directionselection spool is connected by linkage to the selection lever of the transmission. The position of direction selection spool (25) is controlled by the position of the selection lever.

Operation

When the engine is started, with the selection lever in NEUTRAL, oil goes through a passage in valve body (14) to modulating valve (19). The oil goes around the modulating valve to differential and safety valve (20). The oil goes through a passage in the valve. Part of the oil goes out of valve body (14) to selection valve body (24). The position of speed selection spool (29) lets this oil start to fill the No. 3 clutch. Part of the oil opens the poppet valve in differential and safety valve (20). This oil goes into the chamber between valve (20) and the cover of valve body (14). Since valve (20) is against the cover, a passage is open from the chamber to the right end of speed selection spool (29). When speed selection spool (29) is in the NEUTRAL position, the passage is closed to reservoir (26). The pressure of the oil in the chamber increases. Valve (20) moves away from the cover of valve body (14).

When the area behind the piston in the No. 3 clutch is filled with oil, the pressure of the oil increases. The increase in pressure will move modulating valve (19) against the force of its spring. The movement of modulating valve (19) closes the passage from transmission oil filter (22). This stops theincrease in pressure in the speed clutch for a short period of time.

At the same time, the increase in the pressure in the speed clutch moves differential and safety valve (20) against the force of its spring. Differential and safety valve (20) moves until the orifices in the spool are opened to a passage that goes to selection valve body (24). The position of speed selection spool (29) keeps the oil from going to a direction clutch. The differential and safety valve also closes a passage from valve body (14) to the reservoir. The movement of the differential and safety valve lets oil go through the center of the differential and safety valve to check valve (15). The check valve



moves and closes a passage from valve body (14) to the reservoir. When both of the passages are closed, pressure oil goes through an orifice in check valve (15) to the chamber behind load piston (13).

As the pressure of the oil in the chamber behind load piston (13) increases, the load piston will move toward modulating valve (19). The pressure of the oil behind the load piston and the force of the spring will move modulating valve (19). The modulating valve opens the passage from the filter to differential and safety valve (20). The position of safety valve (20) lets the oil go from valve body (14) to selection body (24). This causes the pressure of the oil in the speed clutch to increase.

As the pressure in the speed clutch increases, modulating valve (19) moves and stops the oil to the speed clutch again. This causes differential and safety valve (20) to again move against the force of its spring. The oil can again go through the orifice in check valve (15) to the chamber behind load piston (13). The pressure of the oil behind the load piston and the force of the spring again move the modulating valve. The modulating valve again opens and lets oil go to the speed clutch. This cycle opens and lets oil go to the speed clutch. This cycle takes place again and again until the load piston moves completely against its stop. Speed clutch pressure is then at a maximum of approximately 375 psi (2600 kPa). The pressure stopped by direction selection spool (25) and felt on load piston (13), is approximately 55 psi (380 kPa) less than the speed clutch pressure. This gradual increase in pressure is called modulation. Modulating valve (19) gives modulation for all speed and directional clutches.

The force of the spring which is acting on the end of differential and safety valve (20), is approximately 55 psi (380 kPa) the same as the pressure acting on the opposite end. Thus, the valve will balance at a point where the pressure in the direction clutch is about 55 psi (380 kPa) less than the pressure in the speed clutch.

When the selection lever is moved from NEUTRAL to FIRST REVERSE, speed selection spool (29) moves to the left. The movement of spool (29) lets oil in the No. 3 clutch go to reservoir (26) and to the No. 5 clutch. At the same time, speed selection spool (29) opens a passage to direction spool (25).The direction selection spool is in a position to let oil go to the No. 2 clutch.

As the pressure in the No. 3 clutch decreases, the force of the spring moves differential and safety valve (20). Differential and safety valve (20) moves and opens a passage to reservoir (26). The pressure in the direction clutch circuit decreases.

The oil fills the No. 5 clutch. As the pressure in the piston behind the No. 5 clutch increases, the pressure is felt at the bottom of differential and safety valve (20). The differential and safety valve moves against the force of its spring and closes the passage to reservoir (26). Oil goes through the differential and safety valve and out valve body (14) to valve body (24). The oil goes through a passage in valve body (24) to the No. 2 clutch. The oil starts to fill the No. 2 clutch.

At this time, the modulating valve (19) and load piston (13) go through the modulation sequence until the full pressure of operation are reached in the speed and direction clutches. The hydraulic controls are now in the positions shown in the schematic, HYDRAULIC CONTROLS (FIRST SPEED REVERSE).

The same sequence is done for each shift. When the transmission selection lever is moved, speed selection spool (29) moves and decreases the pressure of the oil in the clutch circuits. At the same time, speed selection spool (29) opens passages for pressure oil to the clutches for the next speed. As the pressures in the clutch circuits increase, the speed clutch and then the direction clutch are engaged. When the full pressures of operation are reached, the machine will be in the next speed. The operation of the hydraulic controls is the same when both speed and direction are changed.



Safety Valve

The safety valve (20) prevents movement of the machine if the engine is started in a speed position or if the pressure in the hydraulic controls decreases.

When the machine is in operation, with the selection lever in a speed position, pressure oil in the chamber between valve (20) and the cover of valve body (14) keeps valve (20) away from the cover. The position of the spool lets oil go to the speed and direction clutches. The clutches for that speed are engaged and the operation of the transmission hydraulic controls is normal.

When the pressure of the oil in the chamber is low (engine stopped), valve (20) is all the way against the cover of valve body (14). Valve (20) will not move until the pressure in the chamber increases.

When the engine is started with the selection lever in a speed position, the oil from modulating relief valve (19) goes to valve (20). Since the pressure in the chamber is low, valve (20) is all the way against the cover. Oil goes through a passage in the valve. Part of the oil goes out of valve body (14) to selection valve body (24). This oil starts to fill a speed clutch. Part of the oil from modulating valve (19) opens the poppet valve in valve (20). This oil goes into the chamber between valve (20) and thecover of valve body (14). Since valve (20) is against the cover, a passage is open from the chamber to the right end of speed selection spool (29). When speed selection spool (29) is in a speed position, the right end is open to reservoir (26). The pressure of the oil in the chamber between valve (20) and valve body (14) does not increase. Valve (20) does not move and stops the oil to the direction clutch. Since both a speed and direction clutch must be engaged in the transmission, the machine will not move.

The poppet valve in valve (20) will not let the valve move all the way against the cover when the transmission makes a shift.

The selection lever must be moved to NEUTRAL before oil can go to the direction clutch circuit. When the selection lever is in NEUTRAL, speed selection spool (29) closes the passage at the right end of the spool to reservoir (26). The pressure in the chamber between valve (20) and the cover canincrease. Valve (20) moves and oil can go to the direction clutch circuit.

Relief Valve For Torque Converter Outlet

Relief valve (3) for the converter outlet controls the rate that oil is released from the torque converter and keeps the pressure in the torque converter constant.

Pressure oil from torque converter (1) goes into relief valve body (2) to relief valve (3). The oil goesthrough a passage in relief valve (3) to move the poppet against the force of its spring. When the poppet valve opens, the chamber between relief valve (3) and the cover of valve body (2) fills with pressure oil.

The pressure oil can now move the relief valve against the force of the spring. When the pressure ofthe oil in the chamber becomes higher than the force of the spring, the valve spool moves. The movement of the valve spool opens a passage to temperature bypass valve (5). The valve spool will move and release pressure oil from the torque converter until the pressure of the oil in the torque converter is approximately 42 psi (290 kPa).



Oil Temperature Bypass Valve

Oil temperature bypass valve (4) controls the amount of oil that can go through air-cooled oil cooler (7). The bypass valve is controlled by the temperature of the oil from torque converter outlet relief valve (3).

When the temperature of the oil is less than 135F (57C), valve (4) is open and lets all the oil from valve (3) go to water-cooled oil cooler (5). When the temperature of the oil reaches 135F (57C), valve (4) starts to close. Most of the oil continues to go through water-cooled oil cooler (5) but some of the oil will go through air-cooled oil cooler (7). As the temperature of the oil increases, valve (4) continues to close with more of the oil directed through air-cooled oil cooler (7) before it goes through water-cooled oil cooler (5). When the temperature of the oil reaches 170F (77C), valve (4) will be completely closed, this causes all the oil to go through air-cooled oil cooler (7) before it finally passes through water-cooled oil cooler (5).

From the water-cooled oil cooler the oil goes to lubrication relief valve (8) where it is directed to the front and rear parts of the transmission for component lubrication.

Torque Divider

TORQUE DIVIDER OPERATION

1. Torque divider housing. 2. Housing. 3. Diesel engine flywheel. 4. Ring gear. 5. Impeller. 6. Sun gear. 7. Outlet passage.

8. Turbine. 9. Output shaft. 10. Planetary carrier. 11. Inlet passage. 12. Planetary gears (three). 13. Carrier. 14. Stator.

The torque divider connects the engine to the planetary transmission. This connection is both a hydraulic connection and a mechanical connection. The hydraulic connectio is through a torque converter. The mechanical connection is through a planetary gear set.

The torque converter uses oil from the transmission hydraulic controls to multiply the torque to the transmission. When the machine is working against a low load, the torque multiplication is low. When



the machine is working against a high load, the torque multiplication is higher. A higher torque can then be sent to the transmission during high load conditions. The planetary gear set also multiplies the torque from the engine by making an increase in the mechanical advantage through its gears. This torque multiplication also makes an increase as the load on the machine becomes higher. During no load conditions, neither the torque converter or the planetary gear set can multiply the torque from the engine.

The torque divider is installed into the engine flywheel. The torque divider housing (1) is installed on the engine flywheel housing. Output shaft (9) is connected to the planetary transmission. A bearing at the rear of housing (1) holds the torque divider in alignment with the flywheel.

The components of the planetary gear set are: a sun gear (6), planetary carrier (10), planetary gears (12) and ring gear (4). Sun gear (6) is connected to flywheel by splines. Planetary carrier (10) is connected to output shaft by splines. Planetary gears (12) are held by planetary carrier (10) and are engaged with the sun gear (6) and ring gear (4).

The components of the torque converter are: housing (2), impeller (5), turbine (8) and stator (14). Housing (2) is connected to the flywheel by splines. Impeller (5) is connected to housing (2) by bolts. The turbine (8) is connected to ring gear (4) by splines. Stator (14) is connected to carrier (13) by bolts. Carrier (13) is connected to the torque divider housing (1) and can not turn.

Oil for the operation of the torque converter is from the transmission hydraulic controls. A relief valve for converter inlet controls the pressure of the oil to the torque converter. A relief valve for converter outlet controls the pressure of the oil in the converter.

Torque Divider Operation

The torque converter is driven by the engine through housing (2). The planetary gear set is driven bythe engine through sun gear (6). These connections let the torque output of the engine go in two separate directions. Because of the larger radius of ring gear (4), most of this torque is sent by the torque converter through the ring gear to planetary gears (12). The remainder of the torque is sent by sun gear (6) to planetary gears (12). If planetary carrier (10) has no resistance to rotation (no load), sun gear (6), planetary gears (12), planetary carrier (10) and ring gear (4) will turn at the same speed. The torque from the converter and from the planetary gear set is now through the planetary carrier to output shaft (9) and the planetary transmission. Neither the torque converter or the planetary gear set can multiply the torque from the engine when they are turning at the same speed.

When the machine has a load, planetary carrier (10) has a resistance to ratation. Since sun gear (6) is turning at the rpm of the engine, this resistance to rotation causes planetary gears (12) to turn on their shafts. Their rotation is opposite the rotation of ring gear (4). This causes a decrease in the speed of the ring gear. Since turbine (8) is connected to the ring gear, a decrease in speed will cause the torque converter to multiply the torque of the engine from housing (2). The torque multiplication is sent to planetary carrier (10) and the output shaft through the ring gear.

With the decrease in the speed of the ring gear, the torque of the engine through sun gear (6) and the planetary gear set also multiplies. This torque multiplication is also sent to planetary carrier (10) and the output shaft.

If the resistance to rotation of planetary carrier (10) becomes higher (more load on the machine), the speed of the ring gear will decrease more. The slower speed will let the torque multiplication through both the torque converter and the sun gear become higher. If the resistance to rotation of the planet



carrier becomes high enough, the ring gear will stop. During some very high load conditions, the rotation of the planetary carrier and the output shaft will also stop. This will cause the ring gear to turn slowly in the opposite direction. At this time the torque multiplication of the torque multiplication of the torque converter and the sun gear is at its maximum.

Torque Converter Operation

Oil for the operation of the torque converter goes through inlet passage (11) in carrier (13) to impeller (5). The rotation of the impeller gives force to the oil. The impeller sends the oil toward the outside of the impeller, around the inside of housing (2) to turbine (8). The force of the oil hitting the blades of the turbine causes the turbine to turn. Since the turbine is connected to ring gear (4), torque is sent to planetary gears (12). At this point in time, the torque given to the turbine by the force of the oil from the impeller can not be more than the torque output of the engine to the impeller.

As the oil goes from the turbine, it is moving in a direction opposite to the direction of impeller (5)rotation. Stator (14) causes the oil to change direction. Since the stator is connected to carrier (13) and can not turn, most of the oil is sent back to impeller (5). The remainder of the oil goes from the stator through outlet passage (7) to the oil cooler and the transmission lubrication system.

The force of the oil from the stator can now add to the torque output from the engine to the impeller. This extra force can give an increase to the torque output of the engine to the turbine. The larger the difference between the speeds of the impeller and the turbine, the larger the amount of force of the oil from the stator. Since it is the load on the machine that changes the speed of the turbine, the higher the load, the larger the difference in the speeds of the impeller and the turbine. It is then the different loads on the machine that control the amount of torque multiplication that the force of the oil from thestator can add.

FLOW OF OIL THROUGH TORQUE CONVERTER

2. Housing. 5. Impeller. 8. Turbine. 14. Stator.

Torque Divider Lubrication

Oil for the lubrication of the torque divider bearings and the planetary gear set is from the supply used for the operation of the torque converter. Bearings (2) are constantly running in oil. Bearings and gears in planetary gear set (5) and pilot bearing (3) get lubrication through passages in output shaft (1). Output shaft bearing (4) gets lubrication from normal oil leakage by a piston ring-type seal.



TORQUE DIVIDER LUBRICATION

1. Output shaft. 2. Bearings. 3. Pilot bearing. 4. Output shaft bearing. 5. Planetary gear set.

Transmission - (Power Shift)

The transmission has three speeds FORWARD and three speeds REVERSE. It has planetary gear systems and five hydraulic clutches.



CLUTCH OPERATION (Typical Example)

1. Piston. 2. Spring. 3. Plates. 4. Ring gear. 5. Discs. 6. Clutch housing.

The five transmission clutches are the disc type and in separate housings. Each clutch has discs (5)and plates (3). The inside teeth of discs (5) are engaged with the outside teeth of ring gear (4). Notches on the outside diameter of plates (3) are engaged with pins in the clutch housing. The pins keep the plates from turning.

In the example above, springs (2) are between clutch housing (6) and piston (1). The springs keep the clutches disengaged (not engaged). The clutches are engaged when oil is sent into the area behind piston (1). When the pressure of the oil in the area behind the piston increases, the piston moves to the right. The piston moves against the force of spring (2) and pushes the discs and plates together. The clutch is now engaged. The discs keep ring gear (4) from turning. When the clutch is released, the pressure in the area behind piston (1) decreases and the force of spring (2) moves the piston to the left. The discs and plates are now apart. The clutch is not engaged.

CLUTCH IDENTIFICATION

The two front clutches (No. 1 and No. 2) are direction clutches. The No. 1 clutch is the FORWARD direction clutch. The No. 2 clutch is the REVERSE direction clutch. The three rear clutches (No. 3,No. 4 and No. 5) are speed clutches.

A speed and a direction clutch must be engaged in the transmission before power goes through the transmission.

NOTE: In the drawings that follow, only the parts that are turning and sending power are a darker color.



COMPONENT LOCATION

1. No.5 planet gear

2. No.5 clutch ring gear.

3. No.4 inner planet gear.



6. No.4 clutch.

7. No.3 planet gear.

8. No.3 clutch.




10. No.2 clutch.


12. No.1 clutch.



15. No.2 carrier.

16. No.1 sun gear.

17. Transfer gear.

18. No.2 sun gear.

19. Input shaft.

20. Bevel pinion drive gear.

21. No.3 sun gear.

22. Bevel pinion.

23. No.1 carrier.

24. No.5 sun gear.

25. No.4 sun gear.

26. No.4 outer planet gear.

27. Output shaft.





Neutral

NEUTRAL (No. 3 Clutch Engaged)



3. No.5 clutch.



6. No.4 clutch.


8. No.3 clutch.


10. No.2 clutch.


12. No.1 clutch.



15. No.2 carrier.

16. No.1 sun gear.

17. Transfer gear.

18. No.2 sun gear.

19. Input shaft.




21. No.3 sun gear.

22. Bevel pinion.

23. No.1 carrier.

24. No.5 sun gear.

25. No.4 sun gear.


27. Output shaft.



When the transmission control lever is in the NEUTRAL slot, the No. 3 clutch is engaged. However, the construction of the selector control valve is such that pressure oil is not available to the directional valve spool. (A directional clutch and a speed clutch must be engaged to transmit torque to the bevel pinion.)

The No.3 clutch ring gear is held stationary by the engaged clutch. The ring gear is connected to the No.2 carrier (rear carrier); therefore, the No.2 carrier is held stationary. The power flow is transmitted through the input shaft which can be used as a power take-off.

First Speed Forward

POWER FLOW-FIRST SPEED FORWARD (No. 1 and No. 5 Clutches Engaged)



3. No.5 clutch.





12. No.1 clutch.


15. No.2 carrier.

16. No.1 sun gear.

17. Transfer gear.

19. Input shaft.


21. No.3 sun gear.

22. Bevel pinion.

23. No.1 carrier.

24. No.5 sun gear.

27. Output shaft.


When the transmission is in FIRST SPEED FORWARD, No. 1 clutch (12) and No. 5 clutch (3) are engaged. The No. 1 clutch holds ring gear (13) for the No. 1 clutch stationary. The No. 5 clutch holds ring gear (2) for the No. 5 clutch stationary. Input shaft (19) turns No. 1 sun gear (16). The No. 1 sun gear turns No. 1 planetary gears (29).

Since the ring gear for the No. 1 clutch is held by the No. 1 clutch, planetary gears (29) move around the inside of the ring gear. The movement of planetary gears (29) causes No. 1 carrier (23) to turn in the same direction as input shaft (19). No. 1 carrier (23), No. 2 carrier (15) and ring gear (9) for the No. 3 clutch are connected mechanically. As the No. 1 carrier turns, No. 3 planetary gears (7) turn. The No. 3 planetary gears turn ring gear (9) for the No. 3 clutch and No. 3 sun gear (21). The No. 3 sun gear turns output shaft (27). Ring gear (9) turns No. 2 carrier (15). The No. 2 carrier turns No. 5 planetary gears (1).

Since ring gear (2) for the No. 5 clutch is held by the No. 5 clutch, No. 5 planetary gears (1) move around the inside of ring gear (2). The movement of the planetary gears and the No. 2 carrier turns No. 5 sun gear (24). The No. 5 sun gear also turns output shaft (27). As a result, the application of torque to output shaft (27) is divided through No. 5 sun gear (24) and No. 3 sun gear (21). From the output shaft, the power goes through gears (17) and (20) to bevel pinion (22).



Second Speed Forward

POWER FLOW-SECOND SPEED FORWARD (No. 1 and No. 3 Clutches Engaged)


8. No.3 clutch.


12. No.1 clutch.


15. No.2 carrier.

16. No.1 sun gear.

19. Input shaft.

21. No.3 sun gear.

23. No.1 carrier.

27. Output shaft.


When the transmission is in SECOND SPEED FORWARD, No. 1 clutch (12) and No. 3 clutch (8) are engaged. The No. 1 clutch holds ring gear (13) for the No. 1 clutch stationary. The No. 3 clutch holds ring gear (9) for the No. 3 clutch stationary. Input shaft (19) turns No. 1 sun gear (16). The No. 1 sun gear turns No. 1 planetary gears (29).

Since the ring gear for the No. 1 clutch is held by the No. 1 clutch, the planetary gears move around the inside of ring gear (13). The movement of the planetary gears causes the No. 1 carrier (23) to turn in the same direction as input shaft (19). As the No. 1 carrier turns, No. 3 planetary gears (7) turn.

Since ring gear (9) for the No. 3 clutch is held by the No. 3 clutch, planetary gears (7) move around the inside of ring gear (9). The movement of planetary gears (7) causes No. 3 sun gear (21) to turn.



The No. 3 sun gear turns output shaft (27). From the output shaft, the power goes through the transfer gear and bevel pinion gear, to the bevel pinion.

Third Speed Forward

POWER FLOW-THIRD SPEED FORWARD (No. 1 and No. 4 Clutches Engaged)



6. No.4 clutch.



12. No.1 clutch.


15. No.2 carrier.

16. No.1 sun gear.

19. Input shaft.

21. No.3 sun gear.

23. No.1 carrier.

25. No.4 sun gear.


27. Output shaft.


When the transmission is in THIRD SPEED FORWARD, the No. 1 clutch (12) and the No. 4 clutch (6) are engaged. The No. 1 clutch holds ring gear (13) for No. 1 clutch stationary. The No. 4 clutch



holds ring gear (5) for the No. 4 clutch stationary. Input shaft (19) turns No. 1 sun gear (16). The No. 1 sun gear turns No. 1 planetary gears (29).

Since the ring gear for the No. 1 clutch is held by the No. 1 clutch, planetary gears (29) move around the inside of the ring gear. The movement of planetary gears (29) causes No. 1 carrier (23) to turn inthe same direction as input shaft (19). The No. 4 sun gear (25) is connected to the No. 1 carrier. The No. 1 carrier turns the No. 4 sun gear. The No. 4 sun gear turns No. 4 inner planetary gears (4). The planetary gears (4) turn No. 4 outer planetary gears (26).

Since ring gear (5) for the No. 4 clutch is held by the No. 4 clutch, planetary gears (26) move around the inside of the ring gear. The movement of planetary gears (26) causes No. 2 carrier (15) to turn inthe opposite direction as No. 1 carrier (23).

Since ring gear (9) for the No. 3 clutch is connected to the No. 2 carrier, the No. 2 carrier turns ring gear (9). The ring gear turns No. 3 planetary gears (7). The No. 3 planetary gears turn No. 3 sun gear (21) in the same direction as the No. 1 carrier and the input shaft. The No. 3 sun gear turns output shaft (27). From the output shaft the power goes through the transfer gear and bevel pinion gear, to the bevel pinion.

Second Speed Reverse

POWER FLOW-SECOND SPEED REVERSE (No. 2 and No. 3 Clutches Engaged)


8. No.3 clutch.


10. No.2 clutch.



15. No.2 carrier.

18. No.2 sun gear.



19. Input shaft.

21. No.3 sun gear.

23. No.1 carrier.

27. Output shaft.


When the transmission is in SECOND SPEED REVERSE, No. 2 clutch (10) and No. 3 clutch (8) are engaged. The No. 2 clutch holds ring gear (11) for the No. 2 clutch stationary. The No. 3 clutch holds ring gear (9) for the No. 3 clutch stationary. Input shaft (19) turns No. 2 sun gear (18). The No. 2 sun gear turns No. 2 inner planetary gears (14). Planetary gears (14) turn No. 2 outer planetary gears (28).

Since ring gear (11) for the No. 2 clutch is held by the No. 2 clutch, planetary gears (28) move around the inside of the ring gear. The movement of planetary gears (28) causes No. carrier (23) to turn in theopposite direction as input shaft (19). As the No. 1 carrier turns, No. 3 planetary gears (7) turn.

Since ring gear (9) for the No. 3 clutch is held by the No. 3 clutch, planetary gears (7) move around the inside of ring gear (9). The movement of planetary gears (7) causes No. 3 sun gear (21) to turn. The No. 3 sun gear turns output shaft (27) in the opposite direction of input shaft (19). From the output shaft, the power goes through transfer gear and bevel pinion gear, to the bevel pinion.

First And Third Speeds Reverse

For first speed reverse the No. 2 and No. 5 clutches are engaged. The operation is almost the same as first speed forward. The difference is that the No. 2 gear train is used instead of the No. 1. The extra set of planet gears in the No. 1 carrier causes the No. 1 carrier rotation, and therefore the output shaft rotation, to be reversed.

For third speed reverse the No. 2 and No. 4 clutches are engaged.



Transmission Lubrication

TRANSMISSION LUBRICATION

1. Passage in transfer gear case.

2. Bearing drain passage.

3. Passage in bearing cage.

4. Front bearing.

5. Passage through the clutch housing.

6. Passage in front bearing cage.

7. No. 1 carrier lubrication tube.

8. No. 2 carrier lubrication tube.

9. Transmission lubrication relief valve.

Oil from the oil cooler flows to the transmission lubrication relief valve, mounted on the front of thetransmission. From here is directed through two passages to the No. 1 and No. 2 planet carriers. The relief valve is a spring-loaded dump valve. When the pressure of the lubricating oil exceeds the force of the dump return spring, the valve moves against the spring allowing excess oil to flow through the orifices in the dump valve, returning to the sump.

The oil flows through the No. 1 and No. 2 carrier lubrication tubes.



The oil passing through the No. 1 carrier tube flows through a passage in the front bearing cage and lubricates the bearings. An oil manifold directs oil to the passages in the planet gear shafts to lubricate the planet gear shaft bearings in the No. 1 carrier.

LUBRICATION RELIEF VALVE

1. Port to No. 1 planet carrier. 2. Dump valve. 3. Dump valve return spring. 4. Dump chamber. 5. Port to No. 2 planet

carrier.

The oil passing through the No. 2 carrier lubrication tube flows through a passage in the clutch housings to a passage in the transfer gear case. The oil passes through the rear bearing cage and lubricates the No. 2 carrier planet gear shaft bearings. Lateral passages in the plate assembly between the No. 1 and No. 2 clutch housings direct some of the oil to spray on the clutch plates and discs for lubrication and cooling. The other components of the transmission and transfer drive are splash lubricated. The oil is then returned to the sump.



Hydraulic System - (Direct Drive)

TRANSMISSION AND STEERING CLUTCH OIL SYSTEM SCHEMATIC (Direct Drive)

1. Hydraulic control mechanism for left brake.

2. Relief valve for steering clutch controls.

3. Oil filter.

4. Oil pump.

5. Hydraulic control valve for the steering clutches.

6. Oil cooler.

7. Hydraulic control mechanism for right brake.

8. Transmission case.

9. Reservoir in steering clutch and bevel gear case.

10. Transmission lubrication regulation valve.




12. Scavenge pump.

13. Flywheel clutch housing.

A. Transmission oil pump.

B. Left steering clutch piston.

C. Right steering clutch piston.

D. Left brake booster.

E. Right brake booster.

F. Transmission lubrication.

G. Transmission oil pump.

Introduction

The hydraulic system has a common reservoir. It gives lubrication oil for the bevel gear and pinion and transmission. It also provides cooling oil for the flywheel clutch, steering clutches and brakes. It also gives pressure oil for the operation of the hydraulic controls for the steering clutches and brakes.

Operation

Oil is pulled from reservoir (9) through magnetic screen (11) by oil pump (4).

Pump (4) sends pressure oil to oil filter (3). The oil goes through the filter. If the oil filter element hasrestrictions, a bypass valve in the filter lets the oil go around the filter.

From filter (3), oil goes to relief valve (2) for the steering clutches and brakes.

Relief valve (2) sends pressure oil to hydraulic control valve (5) for the steering clutches and brakes. Any oil not used by the steering clutches or brakes is sent to flywheel clutch housing (13). If there are restrictions to the flow of oil, relief valve (2) will open and let the flow of oil go to the flywheel clutch housing.

The oil in flywheel housing (13) is used for lubrication of internal components. After the internal components are lubricated, the oil goes to the bottom of housing (13) where scavenge pump (12) pulls the oil through a screen in the bottom of the housing, and sends it to oil cooler (6).

After the oil is made cool at oil cooler (6), the oil is sent to transmission lubrication regulation valve (10). Regulation valve (10) limits the pressure of the lubricating oil and directs excess oil to the transmission sump.

Hydraulic Pump

The hydraulic pump is a single section gear-type pump located to the upper left rear side of the engineflywheel housing.

Drive gear (6) has splines and is driven by a gear in the flywheel housing. Gear (6) turns idler gear (9). During normal operation, oil from the steering clutch and bevel gear case goes into the lower part



of the pump through manifold assembly (5). The oil is then sent through a passage to the lower part of body (4). The oil fills the space between the gear teeth. The gears turn and the oil is sent out passage (12) of manifold assembly (5) to give pressure oil to the hydraulic system.

HYDRAULIC PUMP ASSEMBLY (VIEW FROM TOP)

1. Bolt. 2. Dowel. 3. Cover assembly. 4. Body. 5. Manifold assembly. 6. Drive gear. 7. Bearings. 8. Oil seal. 9. Idler gear.

10. O-ring seal. 11. O-ring seals. 12. Passage. 13. Bearings.

Magnetic Screen

The magnetic screen is located in the system between the reservoir in the steering clutch and bevel gear case and the inlet to the hydraulic oil pump.

Oil from the reservoir comes into the magnetic screen through the bottom. As the oil flows through tube assembly (8) toward the top, it goes through the openings between magnets (6). The magnets are installed on the tube assembly so that the same magnetic ends are next to each other.



MAGNETIC SCREEN CONSTRUCTION

1. O-ring seal. 2. Cover. 3. Wave washer. 4. Housing. 5. Outlet. 6. Magnets. 7. Screen. 8. Tube assembly. 9. O-ring seal.

As the oil goes over the magnets, metal particles are stopped and held by the magnets. These magnets will not let the metal particles go with the oil through the hydraulic system.

The oil then goes through screen (7) on its way to outlet (5). As the oil goes through the screen, other foreign particles are stopped and can not go into the hydraulic system.

From outlet (5), the oil is sent to the inlet port of the hydraulic oil pump.



Oil Filter

OIL FILTER CONSTRUCTION

1. Cover assembly. 2. Bolts. 3. O-ring seal. 4. Bypass valve. 5. Spring. 6. Washer. 7. Filter element. 8. Retainer. 9. Seal.

10. Spring. 11. Filter housing. 12. Plug.

Pressure oil from the hydraulic oil pump goes in filter housing (11) through an inlet passage near the top of the housing. Oil fills the space between filter element (7) and the inside wall of housing (11). During normal operation, the oil goes through element (7) and then goes out the bottom of the filter housing through an outlet tube. As the oil passes through the filter element, foreign particles are stopped and can not go through the hydraulic system.

If filter element (7) becomes full of debris (clogged), oil can not go through. At this time, pressure oil moves bypass valve (4) against the force of its spring and the valve will open.

This lets the oil flow out the bottom of the filter housing through the outlet tube without restriction.

Since the oil that goes through bypass valve (4) is not cleaned of debris, damage to other components in the hydraulic system will result.

Correct maintenance should be used to make sure that the filter element does not become full of debris (clogged) and stop the flow of clean oil to the hydraulic oil system.



Transmission Oil Cooler

Coolant from the engine comes in at the front end. The coolant goes through the many long tubes that are in the cooler. After the coolant goes through the tubes, it goes out through the other end of the cooler and returns to the engine cylinder block.

TRANSMISSION OIL COOLER (SCHEMATIC)

1. Oil cooler.

Transmission and hydraulic system oil comes from the torque converter outlet. This oil comes in to the rear of the cooler. The flow of oil is around and along the many tubes inside the cooler. In this procedure, heat is removed from the oil and is given to the coolant of the engine. The engine coolant goes through the tubes inside the cooler and takes the heat from the oil. The coolant is then cooled by the cooling system of the engine.

After the oil goes along the tubes in the cooler, it goes out through a passage at the front and has alower temperature. The colder oil then goes to the transmission for lubrication.

Flywheel Clutch - (Direct Drive)

The flywheel clutch is operated manually and is an oil-type. The flywheel clutch sends the torque from the engine through the universal joint to the transmission.

Three driven discs (12) and drive plates (4) sent torque through the flywheel clutch. The action of a cam link and roller assembly against a plate keeps the flywheel clutch engaged. A brake on the clutch shaft is activated when the clutch is released. When the flywheel clutch is fully released, the rotation of the clutch shaft and the upper shaft of the transmission is stopped.



FLYWHEEL CLUTCH

1. Clutch shaft brake drum. 2. Oil pump drive gear. 3. Sliding collar assembly. 4. Drive plates. 5. Plate. 6 Clutch hub. 7.

Cam link and roller assemblies (four). 8. Oil pump. 9. Clutch shaft. 10. Oil pump gear. 11. Yoke assembly. 12. Driven

discs.

Drives plates (4) have teeth on the outer edge. The teeth are engaged with teeth on the inside of the engine flywheel. Driven discs (12) have teeth on the inside edge. The teeth are engaged with teeth on the outside of hub (6). Splines connect hub (6) to clutch shaft (9). One end of clutch shaft (9) is a drive flange. The drive flange is connected to the universal joint. The universal joint is connected to the upper shaft of the transmission. Dirt is kept out of the clutch housing by a lip-type seal in theclutch housing. The seal also keeps oil in the clutch housing. The drive flange end of the clutch shaft is held by a bearing. Hub (6) is held in the center of the engine flywheel by a bearing.

Operation

When the flywheel clutch lever is moved to the ENGAGED position, yoke assembly (11) moves collar assembly (3) to the right. Collar assembly (3) is connected to cam link and roller assemblies(7). Cam link and roller assemblies (7) push against plate (5). Plate (5) pushes against driven discs (12) and drive plates (4). The driven discs (12) make contact with the drive plates (4). The friction



between drive plates (4) and driven discs (12) causes the driven discs to turn. The driven discs turn hub (6). Hub (6) turns clutch shaft (9). Clutch shaft (9) turns the universal joint. The clutch is held ENGAGED by the action of cam link and roller assemblies (7).

When the flywheel clutch lever is moved to the NOT ENGAGED position, yoke assembly (11) pulls collar assembly (3) to the left. The movement of collar assembly (3) releases the action of cam link and roller assemblies (7). Plate (5) no longer pushes against driven discs (12) and drive plates (4). Springs move plate (5) to the left. The driven discs are no longer in contact with the drive plates. The drive plates do not turn the driven discs. Power can not go through the flywheel clutch to the transmission.

After the flywheel clutch is NOT ENGAGED, the clutch shaft can be stopped by further movement of the clutch lever. At this time, the brake lining on the control lever makes contact with brake drum (1) on the clutch shaft. The movement of clutch shaft (9) is stopped.

Lubrication

Oil pump (8) is fastened to the clutch housing. When the engine is in operation, the flywheel turns plate (5). Plate (5) turns gear (2). Gear (2) turns gear (10). Gear (10) turns oil pump (8).

Oil pump (8) pulls oil from the reservoir in the bottom of the engine flywheel housing through a passage and screen. The oil is then sent to the transmission oil cooler.

Oil, from the steering clutch hydraulic control valve, goes into a passage in the flywheel clutch housing. The oil goes through the passage to the output bearing and the clutch shaft. The oil goes through passages in the clutch shaft for lubrication of the inside components. The driven discs and drive plates get lubrication from oil thrown by the clutch shaft and the clutch hub. Passages in clutch hub (6) let oil go to the pilot bearing in the flywheel.

Gearshift And Interlock Mechanism - (Direct

Drive)

There are two transmission shift levers and one flywheel clutch lever to control the gear shift and interlock mechanism. The two transmission shift levers are contained in one housing which is fastened to the right side of the transmission case. The flywheel clutch lever is on a bracket fastened to the left rear of the tractor frame assembly.



GEARSHIFT CONTROL GROUP (VIEWED FROM REAR)

1. Forward-reverse shift lever. 2. Speed selector lever. 3. Forward-reverse shifter fork. 4. Fifth speed shifter fork. 5. Third

and fourth speed shifter fork. 6. First and second speed shifter fork.

Movement of levers (1) and (2) to different positions will give a selection of five FORWARD and four REVERSE speeds. The forward or reverse direction selection is made by forward-reverse shift lever (1), while the desired speed selection is made with speed selector lever (2).



GEARSHIFT CONTROL GROUP (VIEWED FROM RIGHT)

1. Forward-reverse shift lever. 2. Speed selector lever. 7. Lever. 8. Housing. 9. Plunger (four). 10. Plate. 11. Spring (four).

12. Interlock shaft. 13. Shifter shafts (four).

Forward-reverse shifter fork (3) is controlled by lever (1). Shifter forks (4), (5) and (6) are controlled by lever (2).

When flywheel clutch lever (14) is moved to the ENGAGED POSITION, rod (16) pulls lever (7) on the interlock mechanism.

The interlock mechanism, attached to the gear shift housing, holds the shifter forks and transmission gears in position when the clutch is ENGAGED.



The interlock mechanism consists of spring-loaded plungers (9), which fit into notches on shifter shafts (13), and an interlock shaft (12) which is connected by a lever and rod to flywheel clutch control lever (14).

FLYWHEEL CLUTCH AND INTERLOCK LINKAGE

14. Flywheel clutch lever. 15. Rod. 16. Rod.



The cam on the interlock shaft locks the plungers in the notches on the shifter shafts when the flywheel clutch is ENGAGED, this holds the transmission gears so that they will not slide out of position. When the clutch is DISENGAGED, the interlock shaft is turned, and the plungers can thengo out of the notches as the gears are shifted. Only a small load, made by the spring-loaded plungers, is needed to make a shift change.

Transmission - (Direct Drive)

The direct drive transmission is a sliding gear type, enclosed in a case by itself. Two levers are provided in the operator's compartment to obtain the desired speed and direction. The transmission has five speeds FORWARD and four speeds REVERSE. One lever controls the forward-reverseshifter fork, while the other lever controls the speed selection shifter forks. See the subject "GEAR SHIFT AND INTERLOCK MECHANISM," for explanation of shifter fork and control levers operation.



TRANSMISSION GEAR ARRANGEMENT

1. Uppershaft.

2. Countershaft.

3. Bevel pinion shaft.

A. Forward and reverse sliding gear.

B. First speed gear.

C. Second speed gear.

D. Third speed gear.

E. Fourth speed gear.

F. Fifth speed gear.

G. Reverse drive gear.



H. First speed sliding gear.

I. Second speed sliding gear.

J. Third speed sliding gear.

K. Fourth speed sliding gear.

L. Fifth speed sliding gear.

M. Reverse idler gear.

The interlock mechanism, actuated by the flywheel clutch control lever, locks the sliding gears in position when the flywheel clutch is ENGAGED.

NOTE: Reverse gear (G) is always in mesh with reverse idler gear (M).

TRANSMISSION SHAFT LOCATIONS (FRONT VIEW)

1. Upper shaft. 2. Countershaft. 3. Bevel pinion shaft.



Transmission Lubrication

Lubrication oil from the oil cooler is sent through an inlet tube to oil manifold (1), which sprays oil down and over the transmission gears. The location of transmission lubrication regulator valve (2) is on the front of the transmission case at the end of manifold (1). It limits the pressure of the lubrication oil and directs extra oil to the transmission sump. Cored passages (3) in the transmission case send oil from the valve to the forward bearings of upper shaft (4), countershaft (5) and bevel pinion shaft (6). Drilled passage (7) in shaft (6) carries oil to a cross-drilled passage, which directs the oil to the reverse idler gear bearing. The bearings on the rear of shafts (4), (5) and (6) are splash lubricated.


1. Manifold. 2. Regulator valve. 3. Passages.




4. Upper shaft. 5. Countershaft. 6. Bevel pinion shaft. 7. Drilled passage.

Steering Clutches, Brakes And Final Drives



Steering Clutches And Final Drives

STEERING CLUTCH

1. Bearing cage. 2. Bevel gear. 3. Bevel gear shaft. 4. Disc assemblies. 5. Pressure plates. 6. Inner springs. 7. Bearing cage.

8. Hub. 9. Piston. 10. Steering clutch inner drum. 11. Steel discs. 12. Outer springs.

The main components of the steering clutches and final drives are: bevel gear (2), bevel gear shaft (3), steering clutch inner drum (10), disc assemblies (4), steel discs (11), steering clutch outer drum (13) [also the brake drum], final drive pinion (15), idler pinion (16), final drive gear (21), sprocket shaft (20) and sprocket (18).

The bevel gear and steering clutches are in the bevel gear and steering clutch case. The bevel gear case is the reservoir for the transmission and steering hydraulic systems. As the bevel gear turns lubricant is thrown on the bevel gear, bevel pinion and steering clutches for lubrication. The bearings for the bevel gear shaft get lubrication from the control valve for the steering clutches.

The final drive cases are fastened to the bevel gear and steering clutch case. The final drive cases are reservoirs for oil for the final drives.

With a steering clutch engaged, the force of springs (6) and (12) keeps pressure plate (5), steel discs (11) and disc assemblies (4) against inner drum (10). Power goes from the inner drum, through the discs, to the outer drum. The steering clutches are normally engaged.

With a steering clutch released, pressure oil from the hydraulic controls for the steering clutches moves piston (9) toward the outside of the machine. The piston pushes on the spring retainer. The spring retainer pushes on springs (6) and (12) and puts them in compression. At the same time, the spring retainer pushes pressure plate (5) toward the outside of the machine. The pressure plate is now



not in contact with steel discs (11) and disc assemblies (4). The disc and disc assemblies are not held together. Power can not go from the inner drum to the outer drum.

FINAL DRIVE

13. Steering clutch outer drum (also brake drum). 14. Hub. 15. Final drive pinion. 16. Idler pinion. 17. Duo-Cone seals.

18. Sprocket. 19. Duo-Cone seals. 20. Sprocket shaft. 21. Final drive gear. 22. Support. 23. Bearing cage.

Splines connect both ends of bevel gear shaft (3) to a drive hub (8). The drive hubs are fastened to inner drums (10) of the steering clutches. Teeth connect steel discs (11) to the inner drums. Teeth connect disc assemblies (4) to outer drum (13). The outer drum is fastened to drive hub (14) of pinion (15). Pinion (15) is engaged with idler gear (16). The idler gear is engaged with final drive gear (21). Splines connect sprocket (18) to the final drive gear. The teeth of the sprocket are engaged with the track pins.

When a steering clutch is engaged, the flow of power is: From the bevel gear (2) through bevel gear shaft to inner drum (10). The inner drum turns steel discs (11). The steel discs turn disc assemblies (4). The disc assemblies turn outer drum (13). The outer drum turns final drive pinion (15).



The final drive pinion turns idler gear (16). The idler gear turns gear (21). The gear turns sprocket (18). The sprocket turns the track.

When a steering clutch is not engaged, the connection between bevel gear (2) and final drive pinion (15) is broken. Power does not go through the final drive to the track.

Hydraulic Control Valve For The Steering Clutches

Pressure oil is sent to the hydraulic control valve by the transmission oil pump. When the control levers are pulled, levers (8) and (22) move plungers (7) to the left. The plungers move the valve spools (6). The movement of the valve spools lets oil go to the steering clutch pistons. The oil pushes against the pistons. The pistons push against the springs and move the pressure plates away from the disc assemblies. This releases the steering clutches.

HYDRAULIC CONTROL VALVE FOR STEERING CLUTCHES AND BRAKES

1. Chamber. 2. Chamber. 3. Housing. 4. Chamber. 5. Passage. 6. Valve spools. 7. Plungers. 8. Lever. 9. Tube. 10.

Housing. 11. Spring. 12. Slug. 13. Chamber. 14. Passage. 15. Hole. 16. Slot. 17. Washer. 18. Spring. 19. Spring. 20.

Bushing. 21. Retainer. 22. Lever.

Flow of Oil

Pressure oil comes through housing (3) and goes in chamber (1). When the steering clutches are engaged, the position of valve spools (6) keeps the oil in chamber (1).

Passages (5) and (14) are connected to oil lines. The oil lines go to the steering clutch pistons. The steering clutches are released by the movement of the control levers. The steering clutches arereleased when the control levers are pulled until a resistance is felt.

When the right control lever is pulled PART WAY, plunger (7) moves against spring (19). The force of spring (19) moves valve spool (6) against spring (11). The movement of valve spool (6) opens chamber (1) to chamber (2). Pressure oil goes from chamber (2) to passage (14). The oil goes from



passage (14) and through an oil line to the piston for the right steering clutch. As the pressure behind the steering clutch piston increases, the pressure increase is felt in chamber (13) through hole (15) in the valve spool. The pressure in chamber (13) becomes the same as the pressure behind the steering clutch piston. The pressure in chamber (13) against slug (12) adds with the force of spring (11) and moves valve spool (6) to the right. The movement of valve spool (6) stops the oil to the steeringclutch piston. Now the valve spool is in a balance position. The balance position is modulation. The pressure against the steering clutch piston is kept constant. The amount of pressure against the steering clutch piston is a result of the position of plunger (7). The amount of force of spring (19) against valve spool (6) is also a result of the position of plunger (7). The amount of pressure that is needed to release a steering clutch is a result of the load on the machine during operation.

RIGHT STEERING CLUTCH RELEASED

1. Chamber. 2. Chamber. 6. Valve spool. 7. Plunger. 11. Spring. 12. Slug. 13. Chamber. 14. Passage. 15. Hole. 19. Spring.

20. Bushing. 21. Retainer.

If a control lever is pulled until a resistance is felt, a steering clutch is fully released. There is nomodulation of valve spool (6). When a steering clutch is fully released, retainer (21) is against bushing (20). If the control lever is pulled beyond the point of resistance, the steering clutch is still fully released and brake action starts.

When the right control lever is pulled ALL THE WAY, plunger (7) pushes against spring (19). Spring (19) moves valve spool (6) to the left until retainer (21) makes contact with bushing (20). Then plunger (7), spool (6) and bushing (20) move to the left against springs (11), (18) and (19) untilbushing (20) makes contact with washer (17). Maximum pressure oil goes from chamber (1) to chamber (2). The oil goes from chamber (2) to passage (14). The oil goes from passage (14) and through an oil line to the piston for the right steering clutch. At this time, maximum pressure oil is against the piston and the steering clutch is fully released. In this position there is no modulation of valve spool (6). At this time, there is also an action of the brakes. See the subject, "BRAKES", in this manual.



RIGHT STEERING CLUTCH FULLY RELEASED AND RIGHT BRAKE FULLY ENGAGED

1. Chamber. 6. Valve spool. 7. Plunger. 11. Spring. 14. Passage. 17. Washer. 18. Spring. 19. Spring. 20. Bushing. 21.

Retainer.

When the right control lever is released, the pressure oil in chamber (13) together with the force of springs (11), (18) and (19) moves valve spool (6) and plunger (7) all the way to the right. The oil behind the steering clutch piston comes back through the oil line to passage (14). The oil goes through passage (14) to chamber (2). The oil goes from chamber (2) through slots (16) and an oil passage to housing (10). This oil is for lubrication of the mechanical linkage. The oil level in housing (10) is controlled by tube (9). The extra oil goes from the housing through tube (9). This oil is for lubrication of the bevel gear and pinion and the bevel gear shaft bearings.



RIGHT STEERING CLUTCH ENGAGED

6. Valve spool. 7. Plunger. 9. Tube. 10. Housing. 11. Spring. 13. Chamber. 14. Passage. 16. Slots. 18. Spring. 19. Spring.

Brakes

Two band-type brakes, one on each steering clutch drum, stop the movement of the machine. The brakes also give assistance to the steering clutches to turn the machine. The operation of each brake gets assistance from a hydraulic control mechanism. The operation of each brake is separate from the other. Both brakes can be held in the "ON" position by pawl (7) on the brake linkage.

BRAKE LINKAGE

1. Link. 2. Shaft. 3. Piston. 4. Bellcrank. 5. Spring. 6. Rod. 7. Pawl. 8. Pin. 9. Pin. 10. Lever. 11. Lever. 12. Shaft. 13.

Strut. 14. Pin. 15. Strut. 16. Shaft.

The operation of both brakes is the same. When a brake pedal is pushed toward the front of the machine, mechanical linkage moves piston (3) in the hydraulic control mechanism. The piston (3) pushes against the roller on bellcrank (4). The bellcrank turns on the shaft (2) and moves the link (1) toward the top. This moves pin (14) toward the top and pins (8) and (9) away from each other. The levers (10) and (11) then turn on shafts (12) and (16). Levers (10) and (11) move struts (13) and (15) toward each other. As the struts move toward each other, they push on the ends of the brake band.This causes the brake band to make contact with the steering clutch drum. Now, the movement of the machine stops or becomes slower.



When the brake pedal is released, spring (5) and springs inside the hydraulic control mechanism move the mechanical linkage and brake pedal. The struts move away from each other. The brake band is not in contact with the steering clutch drum. Now, the brakes are in the "OFF" position.

Both brakes can be held in the "ON" position. Push both brake pedals toward the front of the machine. At the same time, push the parking brake lever forward and down. The parking brake lever is at the right side of the seat. The movement of the lever moves rod (6) and engages the teeth of the pawl (7) with the teeth of the ratchet. The brakes are held in the "ON" position by the link. The links push against the bellcrank (4). To release the brakes, push on the brake pedals and pull the parking brake lever up and backwards.

An oil line sends pressure oil to each brake band. This oil is for lubrication and cooling of the brake bands.

Hydraulic Control Mechanism

Pressure oil is sent to each hydraulic control mechanism. On power shift machines, this oil comes from an oil manifold on the control valve for the steering clutches. On direct drive machines this oil comes from a relief valve on the control valve for the steering clutches. The oil goes in the housing and fills chamber (5).

When the brakes are in the "OFF" position, the oil is kept in chamber (5).

When a brake pedal is pushed forward, lever (12) pushes plunger (2) and valve (6) to the right against piston (9). This closes passage (7) in the piston. The movement of plunger (2) and valve (6) opens passages (10), (14) and (15). The oil goes from chamber (5) through passage (10) and opens plunger (13). The oil goes through plunger (2) to the center of valve (6). The oil goes through holes in valve (6) and out passage (15). The oil goes through passages (15) and (14) and starts to fill the

Documents

TRANSMISION D6D