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Capítulo V. Resultados

5.2 Presentación de resultados

5.2.3 Resultados de Ejecución Presupuestaria (variable dependiente)

5.2.3.2 Ejecución financiera de ingresos y gastos

Directions: Match the component to its primary function.

Maintains high oil pressure to the lockup reducing valve Supplies oil for hydraulic energy transfer

Maintains working pressure within the torque converter When energized, supplies pilot oil to initiate direct drive Relieves excess pressure to the torque converter

Provides a controlled rate of engagement of the lockup clutch

Transfers engine power to the transmission Reduces pump supply pressure to pilot pressure Supplies oil to the lockup clutch

Directions: Modified True/False. If a statement is false, underline or circle the word or words that make the statement incorrect and replace with word(s) to make the statement correct.

a power train Example: F 1. This is an engine class.

1. The inlet relief valve controls the maximum pressure in the torque converter.

2. The parking brake release pump supplies oil to the lockup modulation valve.

3. Lockup clutch oil pressure is controlled by the parking brake release valve.

4. Transmission oil pressure is used to pressurize the torque converter lockup clutch when the torque converter is in direct drive.

5. When the transmission is in REVERSE, the torque converter is in direct drive.

6. Direct drive is in gears FIRST through SEVENTH.

1. Lockup Solenoid 2. Inlet Relief Valve 3. Torque Converter 4. Lockup Reducing Valve 5. Parking Brake Release

Valve

6. Outlet Relief Valve 7. Lockup Modulation Valve 8. Converter Charging Pump 9. Diverter Valve

10. Parking Brake Release Pump

CHAPTER : Power T rain 777D Off Highway T ruck

III-39Page:

POSTTEST

Parking Brake Release Pressure

Pilot Pressure Outlet Pressure Inlet Pressure

Lockup Clutch Pressure Components

Lockup Solenoid Inlet Relief Valve Torque Converter Lockup Reducing Valve Parking Brake Release Valve

Outlet Relief Valve Lockup Modulation Valve Converter Charging Pump Scavenge Pump

Parking Brake Release Pump

Shuttle Valve

2

4

1

7

TO BRAKE COOLING TO BRAKE

COOLING CIRCUIT 10

11

769D - 777D TORQUE CONVERTER HYDRAULIC SYSTEM

12

CHAPTER : Power Train

777D Off Highway Truck

III-40 Page:

POSTTEST

Directions: Use the schematic on page 41. After each statement, circle the correct sequence of events that occurs.

Example: The operator makes a shift from NEUTRAL to FIRST FORWARD and the ground speed increases.

A. 1-Torque converter is in TC drive

2-Ground speed increases and the lockup clutch modulation valve is activated

3-Lockup clutch engages

B. 1-Lockup clutch engages 2-Ground speed

increases and the lockup clutch modulation valve is activated

3-Torque converter is in TC drive

C. 1-Ground speed increases and the lockup clutch modulation valve is activated

2-Lockup clutch engages 3-Torque converter is in

TC drive

C. 1-Parking brake release pump directs oil to lockup reducing valve 2-Pilot oil directed to

lockup solenoid valve 3-Parking brake release oil directed to lockup modulation valve spool A. 1-Parking brake release

oil directed to lockup modulation valve spool 2-Pilot oil directed to

lockup solenoid valve 3-Parking brake release

pump directs oil to lockup reducing valve

B. 1-Parking brake release oil directed to lockup modulation valve spool 2-Parking brake release

pump directs oil to lockup reducing valve 3-Pilot oil directed to

lockup solenoid valve

B. 1-Lockup solenoid valve opens

2-Shuttle valve moves and blocks drain 3-Load piston moves A. 1-Shuttle valve moves

and blocks drain 2-Load piston moves 3-Lockup solenoid valve

opens

C. 1-Load piston moves 2-Lockup solenoid valve

opens

3-Shuttle valve moves and blocks drain

A. 1-Shuttle valve moves and opens drain

2-Lockup solenoid valve closes

3-Load piston moves

C. 1-Lockup solenoid valve closes

2-Shuttle valve moves and opens drain 3-Load piston moves B. 1-Load piston moves

2-Shuttle valve moves and opens drain

3-Lockup solenoid valve closes

III-41 Page:

1. Charging Pump

2. Pressure Control Group 3. Rotary Selector Spool 4. Upshift Solenoid 5. Oil Cooler Relief Valve 6. Priority Reduction Valve 7. Main Relief Valve 8. Scavenge Pump 9. Downshift Solenoid 10. Rotary Actuator 11. Selector Valve Group 12. Neutralizer Valve 13. Oil Cooler 14. Filter 15. Manifold 16. A through H Regulates pressure inside oil cooler

Reduces temperature of transmission oil Removes oil from transmission case Maintains pilot oil pressure

Removes debris from transmission oil Supplies modulated pressures to clutches

Directs oil to move rotary actuator vane clockwise Maintains maximum system pressure

Chooses appropriate clutch combinations for each speed Six valve clutch stations

Moves rotary selector spool

Keeps machine from moving if transmission is started in gear

Supplies oil to all clutches

Directs oil to move rotary actuator vane counterclockwise

Maintains and directs oil pressures to the pressure control group

Directions: Match the component to its primary function.

CHAPTER : Power Train

777D Off Highway Truck

III-42 Page:

POSTTEST

Directions: Modified True/False. If a statement is false, underline or circle the word or words that make the statement incorrect and replace with word(s) to make the statement correct.

a transmission Example: F 1. This is an electrical test.

1. In NEUTRAL, no clutches are engaged.

2. If the machine is started IN GEAR, the neutralizer valve stops the flow of pilot oil.

3. Clutch pressure is maintained by the relief valve.

4. Reverse is an upshift.

5. During a shift, clutches are always drained and then refilled.

6. REVERSE and the first half of FIRST are torque converter drive.

CHAPTER : Power T rain 777D Off Highway T ruck

III-43Page:

POSTTEST

Lube Pressure Components

Scavenge Pump

Priority Reduction Valve Rotary Selector Spool Neutralizer Valve Lube Relief Valve A to C and E to H Pressure Control Group Main Relief Valve Charging Pump Downshift Solenoid Filter

Selector Valve Group Upshift Solenoid Oil Cooler Rotary Actuator Screen

769D- 777D TRANSMISSION HYDRAULIC SYSTEM

CHAPTER : Power Train

777D Off Highway Truck

III-44 Page:

Directions: Use the schematic on page 45. After each statement, circle the correct sequence of events that occurs.

Example: The operator has moved the shift lever from NEUTRAL to FIRST FORWARD.

A. 1-Downshift solenoid is de-energized

2-Upshift solenoid is energized

3-Rotary actuator moves to FIRST SPEED FORWARD

B. 1-Rotary actuator moves to FIRST SPEED FORWARD

2-Downshift solenoid is de-energized

3-Upshift solenoid is energized

C. 1-Upshift solenoid is energized

2-Rotary actuator moves to FIRST SPEED FORWARD

3-Downshift solenoid is de-energized

1. The engine is started with the transmission in NEUTRAL.

2. The engine is started with the gear shift lever in FIRST SPEED FORWARD.

3. During an upshift, the following occurs:

A. 1-Neutralizer valve moves

2-Pilot oil flows through rotary selector spool to one station

3-Downshift solenoid is energized

B. 1-Pilot oil flows through rotary selector spool to one station

2-Downshift solenoid is energized

3-Neutralizer valve moves

C. 1-Downshift solenoid is energized

2-Neutralizer valve moves

3-Pilot oil flows through rotary selector spool to one station

A. 1-Charge pump oil flows to priority reduction valve

2-Pilot oil flows to neutralizer valve 3-Rotary selector spool

blocks charge pump oil to neutralizer valve

C. 1-Pilot oil flows to neutralizer valve 2-Rotary selector spool

blocks charge pump oil to neutralizer valve 3-Charge pump oil flows

to priority reduction valve

B. 1-Rotary selector spool blocks charge pump oil to neutralizer valve 2-Pilot oil flows to

neutralizer valve 3-Charge pump oil flows

to priority reduction valve

A. 1-Charge pump moves the upshift valve 2-Upshift solenoid is

energized

3-Rotary actuator oil moves the downshift valve

B. 1-Upshift solenoid is energized

2-Charge pump oil moves the rotary actuator

3-Rotary actuator moves the rotary selector spool

C. 1-Rotary actuator oil moves the downshift valve

2-Upshift solenoid is energized

3-Charge pump moves the upshift valve

III-45 Page:

rotary actuator.

1. On some ICM transmissions, the Dual Stage Relief Valve is activated T F during torque converter lockup.

2. On all ICM transmission controls, REVERSE is an upshift from T F NEUTRAL and the downshift solenoid is activated whenever the

shift lever is in NEUTRAL.

3. When the transmission shift lever is in a speed other than NEUTRAL, T F the rotary selector spool provides a path to drain for two clutches.

4. On all ICM transmission controls, the priority reduction valve controls T F the pressure of the "pilot oil" that is used to shift the selector piston

in each station.

5. The load piston orifice in an ICM transmission is a "cascade-type" and T F controls the modulation of clutch engagement.

6. In an ICM transmission, the "primary pressure setting" in each station T F can cause harsh shifts when too low and clutch slipping when too high.

7. The "primary pressure settings" are the same for all ICM clutch stations. T F

8. Final clutch pressure is adjusted with shims. T F

9. If the "primary pressure setting" is correct and the final clutch pressure T F is low, the load piston springs should be replaced.

10. When manually rotating the rotary selector spool with the engine T F running, power to the shift solenoids must be disconnected.

Service Training

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