SISTEMA DIRECCION CARGADOR 980G II.pdf

Pruebas y Ajustes 980G Series II Wheel Loader Steering System Número úmero de medio medio -REN -RENR6 R601 0122-06 06

Fecha Fecha de publ public icaci ación ón -01/ -01/08 08/2 /201 011 1

Fecha Fecha de actual actualiz izaci ación ón -09/ -09/08 08/2 /201 011 1 i01681295

Steering System Troubleshooting SMCS - 4300-035

Personal injury or death can result from machine articulation or movement. Machine frames can move and a person can be crushed. Connect the steering frame lock link between the front and rear frames before working on machine.

Personal injury or death can result from escaping fluid under pressure. Escaping fluid under pressure, even a very small pin-hole size leak, can penetrate body tissue and cause serious injury and possible death. If fluid is injected into your skin, it must be treated immediately by a doctor familiar with this type of injury. Always use a board or cardboard when checking for a leak.

NOTICE Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids. Refer to Special Publication, NENG2500, "Caterpillar Tools and Shop Products Guide" for tools and supplies suitable to collect and contain fluids on Caterpillar products. Dispose of all fluids according to local regulations and mandates.

Performance tests for the steering system can be used for a diagnosis of poor performance and for finding the source of oil leaks inside the hydraulic system. This section provides probable causes to a known problem. Since there may be several probable causes, specific inspections or specific instrument tests may be recommended. These inspections and tests will help to identify the cause that is most probable. Note: Make sure that you use hydraulic oil with the correct viscosity for the ambient temperature and for the operating conditions. To determine the correct oil viscosity, see the reference that follows. Reference: For additional information about the various lubricant viscosities for your machine, refer to the section "Lubricant Viscosities" in the appropriate Operation and Maintenance Manual for your machine. Problem List

1. Turning the steering wheel is difficult. 2. The steering wheel will not return to the NEUTRAL position. The machine is steering all of the time. 3. The impact at full articulation is too high. 4. The machine turns too slowly in one direction. 5. The machine turns too slowly in both directions. 6. The machine turns too slowly in both directions only when the machine turns against a load. 7. The machine does not turn when the steering wheel is turned. 8. The machine turns but the operator does not turn the steering wheel. 9. The machine turns too quickly in order to make small steering corrections when the machine moves at fast speeds. Problem 1: The steering wheel is difficult to turn. Probable causes:

1. The port plate in the pilot valve is binding. 2. One or both of the constant velocity joints is binding. 3. The pilot valve spool is binding. 4. The cam and the follower for the pilot valve is binding. Problem 2: The steering wheel will not return to the NEUTRAL position. The machine is steering all of the time. Probable causes:

Performance tests for the steering system can be used for a diagnosis of poor performance and for finding the source of oil leaks inside the hydraulic system. This section provides probable causes to a known problem. Since there may be several probable causes, specific inspections or specific instrument tests may be recommended. These inspections and tests will help to identify the cause that is most probable. Note: Make sure that you use hydraulic oil with the correct viscosity for the ambient temperature and for the operating conditions. To determine the correct oil viscosity, see the reference that follows. Reference: For additional information about the various lubricant viscosities for your machine, refer to the section "Lubricant Viscosities" in the appropriate Operation and Maintenance Manual for your machine. Problem List

1. Turning the steering wheel is difficult. 2. The steering wheel will not return to the NEUTRAL position. The machine is steering all of the time. 3. The impact at full articulation is too high. 4. The machine turns too slowly in one direction. 5. The machine turns too slowly in both directions. 6. The machine turns too slowly in both directions only when the machine turns against a load. 7. The machine does not turn when the steering wheel is turned. 8. The machine turns but the operator does not turn the steering wheel. 9. The machine turns too quickly in order to make small steering corrections when the machine moves at fast speeds. Problem 1: The steering wheel is difficult to turn. Probable causes:

1. The port plate in the pilot valve is binding. 2. One or both of the constant velocity joints is binding. 3. The pilot valve spool is binding. 4. The cam and the follower for the pilot valve is binding. Problem 2: The steering wheel will not return to the NEUTRAL position. The machine is steering all of the time. Probable causes:

1. The port plate in the pilot valve is binding. 2. One or both of the constant velocity joints that are in the steering shaft are binding. 3. The pilot valve spool is binding. 4. The cam and the follower for the pilot valve is binding. 5. The torsion spring in the pilot valve is broken. Problem 3: The impact at full articulation is too high. Probable cause:

1. The neutralizer valves are set incorrectly. Problem 4: The machine turns too slowly in one direction. Probable causes:

1. One of the cushioning orifices is blocked. 2. One of the screens is blocked. Problem 5: The machine turns too slowly in both directions. Probable causes:

1. The neutral pilot pressure is too low. 2. The steering pump margin pressure is too low. 3. Both of the cushioning orifices are blocked. 4. Both of the screens are blocked. Problem 6: The machine turns slowly in both directions only when the machine turns against a load. Probable causes:

1. The high pressure setting for the steering pump is set too low. 2. The backup relief valve in the main steering control valve is stuck open. 3. The backup relief valve in the main steering control valve is leaking. Problem 7: The machine does not turn when the steering wheel is turned. Probable causes:

1. The pilot valve is faulty.

2. The steering control valve spool is sticking. 3. There is a mechanical failure in the steering linkage. 4. Both of the cushioning orifices are blocked and the quad check valve will not open. Problem 8: The machine turns but the operator does not turn the steering wheel. Probable causes:

1. One of the cushioning orifices are blocked. 2. The spool in the steering control valve does not return to the NEUTRAL position correctly. 3. The spool in the pilot valve is binding. 4. The centering spring in the steering control valve is broken. 5. The steering column is binding. 6. One or both of the constant velocity joints for the steering shaft is binding. Problem 9: The machine turns too quickly in order to make small steering corrections when the machine moves at fast speeds. Probable causes:

1. The metering stem in the pilot valve spool is sticking. 2. The main control valve spool does not move freely. 3. The margin pressure of the steering pump is set too high. Copyright 1993 - 2016 Caterpillar Inc. Todos los derechos reservados. Red privada para licenciados del SIS.

Wed Feb 03 2016 14:19:24 GMT-0500 (Hora est. Pacífico, Sudamérica)

Pruebas y Ajustes 980G Series II Wheel Loader Steering System Número de medio -RENR6012-06

Fecha de publicación -01/08/2011

Fecha de actualización -09/08/2011 i06196930

Articulated Hitch - Adjust SMCS - 7057-025-BD

Assembly Instructions for the Upper Hitch

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Illustration 1

g00274757

(1) Bolt. (2) Washer. (3) Pin. (4) Bolt. (5) Washer. (6) Seal. (7) Upper cap. (8) Shim. (9) Bearing cone. (10) Bearing cup. (11) Lower cap. (12) Seal.

1. Install seal (6) in cap (7) . Install seal (12) in cap (11) . Lubricate the seal lips with the lubricant that is being sealed.

2. Coat the bores with 5P-0960 Molybdenum Grease . 3. Cool bearing cups (10) to a temperature of -50° ± 5°C (-58° ± 9°F). 4. Position lower cap (11) and retain the cap with three bolts that are equally spaced. 5. Install lower bearing cup (10) in the bearing housing. Drive the bearing cup downward in order to ensure contact with lower cap (11) . 6. Lubricate bearing cones (9) with oil. Install the bearing cones. 7. Install top bearing cup (10) . Drive the bearing cup downward in order to ensure light contact pressure on the bearing cones. 8. Install shim (8) , upper cap (7) , three bolts (4) and washers (5) . Tighten the bolts to a torque of 100 ± 20 N·m (75 ± 15 lb ft). 9. Install the torquing bolt and tighten the torquing bolt. 10. Apply a torque wrench to the torquing bolt. Read the torque that is necessary to rotate the bearing cones. 11. If the torque is within 2.3 to 13.6 N·m (1.70 to 10.06 lb ft), install the remaining bolts and tighten the bolts. 12. If the torque is less than 2.3 N·m (1.70 lb ft) or if the torque is greater than 13.6 N·m (10.06 lb ft), remove shims or add shims in order to obtain the correct rotating torque. 13. Install all cap bolts (4) and washers (5) . Tighten the bolts to a torque of 100 ± 20 N·m (75 ± 15 lb ft).

Installation Procedure for the Upper Hitch 1. Make sure that the bores in the upper hitch are aligned. Install pin (3) through the bores. 2. Install bolt (1) and washer (2) in order to lock pin assembly (3) in place. Tighten bolt (1) to a torque of 100 ± 20 N·m (75 ± 15 lb ft).

Assembly Instructions for the Lower Hitch

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Il lu st rati o n 2

g 010 5721 3

(1) Spacer. (2) Pin. (3) Seal. (4) Bolt. (5) Washer. (6) Upper cap. (7) Bearing cup. (8) Shim. (9) Bearing cone. (10) Seal. (11) Lower cap. (12) Spacer. (13) Frame. (14) Bolt. (15) Washer. (16) Shim. (17) Bolt. (18) Washer. (19) Plate.

1. Install seal (3) in upper cap (6) . Install seal (10) in lower cap (11) . Lubricate the seal lips with the lubricant that is being sealed. 2. Coat the bores with lubricant from a 5P-0960 Grease Cartridge . 3. Cool bearing cups (7) to a temperature of -50° ± 5°C (-58° ± 9°F). 4. Position lower cap (11) and retain the cap with three bolts that are equally spaced. 5. Install lower bearing cup (7) in the bearing housing. Drive the bearing cup downward in order to ensure contact with lower cap (11) .

6. Lubricate bearing cones (9) with oil. Install the bearing cones. 7. Install top bearing cup (7) . Drive the bearing cup downward in order to ensure light contact pressure on the bearing cones. 8. Install shim (8) , upper cap (6) , three bolts (4) and washers (5) . Tighten the bolts to a torque of 100 ± 20 N·m (75 ± 15 lb ft). 9. Install the torquing bolt and tighten the torquing bolt. 10. Apply a torque wrench to the torquing bolt. Read the torque that is necessary to rotate the bearing cones. 11. If the torque is within 11.3 to 39.6 N·m (8.3 to 29.1 lb ft), install the remaining bolts and tighten the bolts to a torque of 100 ± 20 N·m (75 ± 15 lb ft). 12. If the torque is less than 11.3 N·m (8.3 lb ft) or if the torque is greater than 39.6 N·m (29.1 lb ft), remove shims or add shims in order to obtain the correct rotating torque. 13. Install all cap bolts (4) and washers (5) . Tighten the bolts to a torque of 100 ± 20 N·m (75 ± 15 lb ft).

Installation Procedure for the Lower Hitch 1. Install spacer (12) in lower cap (11) . Install spacer (1) in upper cap (6) . 2. Ensure that the bores in the lower hitch are aligned. 3. Cool pin (2) to -50° ± 5°C (-58° ± 9°F). Install pin (2) through the bores in the lower hitch. 4. Install plate (19) , two bolts (17) and washers (18) . Tighten the bolts. 5. Measure the gap between plate (19) and frame (13) . Build a pack of shims that is equal to the minimum measured gap. Then, subtract the value of 0.25 mm (0.01 inch) from the pack of shims. Install the pack of shims (16) between plate (19) and frame (13) . 6. Install two bolts (17) and washers (18) through plate (19) and into pin (2) . Torque for the two bolts is 900 ± 100 N·m (665 ± 75 lb ft). 7. Install bolts (15) and washers (16) through plate (19) and shims (16) and into frame (13) . Torque for the eight bolts is 100 ± 20 N·m (75 ± 15 lb ft). Copyright 1993 - 2016 Caterpillar Inc. Todos los derechos reservados. Red privada para licenciados del SIS.


Pruebas Pruebas y Ajustes Ajustes 980G Series II Wheel Loader Steering System Número úmero de medio medio -REN -RENR6 R601 0122-06 06

Fecha Fecha de publ public icaci ación ón -01/ -01/08 08/2 /201 011 1

Fecha Fecha de actual actualiz izaci ación ón -09/ -09/08 08/2 /201 011 1 i03601549

Steering Neutralizer Valve - Check and Adjust SMCS - 4330-025; 4330-535

1. Move the machine to a location that is smooth, level, and hard. The location should also be dry and free of debris.

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Il lu st rati o n 1

g0 110 398 5

Steering Frame Lock in the STORED Position (1) Steering frame lock.

2. Move steering frame lock (1) to the STORED position. 3. Ensure that hydraulic oil temperature is above minimum on the gauge. 4. Turn the machine slightly to the right and left in order to circulate warm oil through the steering system.

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Illustration 2 Location of neutralizer valve and stop (5) Engine end frame (6) Non-engine end frame

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g01901654

Illustration 3

g01099658

Typical Example of Neutralizer Valve and Stop (2) Locknut. (3) Striker. (4) Ball of putty. (5) Engine end frame.

5. Place a ball of putty (4) on the left engine end frame (5) . The diameter of ball should be approximately 19 mm (0.75 inches). The ball of putty will be squeezed between the non-engine end frame (6) and the engine end frame (5) . 6. Move the transmission direction control switch to the NEUTRAL position. Start the engine. Raise an empty bucket to a height of approximately 300 mm (11.8 inches). 7. Disengage the parking brake. 8. Run the engine at high idle. Turn the machine all the way to the left. The machines with a steering wheel turn at a rate of one steering wheel revolution per second. The machines with command control steering turn to the full left command within one second. 9. Steer the machine so that the machine is facing straight ahead. Engage the parking brake. Lower the bucket to the ground. Stop the engine. 10. Measure the thickness of the ball of putty (4) . a. If the frames did not contact each other and the thickness of the putty is less than or equal to 15.7 mm (0.62 inch) then adjustment is not necessary. Repeat the procedure for the right

steering neutralizer. Repeat the process starting with Step 5. b. If the frames contact each other or the thickness of the putty is greater than 15.7 mm (0.62 inch) then an adjustment is necessary. Proceed to Step 11. 11. Adjust striker (3) , as needed. Adjust the striker in order to obtain a 12.7 ± 3 mm (0.5 ± 0.12) thickness of putty. Lock striker (3) in place with locknut (2) . 12. Place a ball of putty (4) on the left engine end frame (5) . The diameter of ball should be approximately 19 mm (0.75 inches). The ball of putty will be squeezed between the non-engine end frame (6) and the engine end frame (5) . 13. Move the transmission direction control switch to the NEUTRAL position. Start the engine. Raise an empty bucket to a height of approximately 300 mm (11.8 inches). 14. Disengage the parking brake. 15. Run the engine at high idle. Turn the machine all the way to the left. The machines with a steering wheel turn at a rate of one steering wheel revolution per second. The machines with command control steering turn to the full left command within one second. 16. Steer the machine so that the machine is facing straight ahead. Engage the parking brake. Lower the bucket to the ground. Stop the engine. 17. Measure the thickness of the ball of putty (4) . If necessary, repeat steps 11 through 16 until pressed thickness of putty is 12.7 ± 3 mm (0.5 ± 0.12 inch). 18. Repeat this procedure for the right turn steering neutralizer. Starting with Step 5 Copyright 1993 - 2016 Caterpillar Inc. Todos los derechos reservados. Red privada para licenciados del SIS.





Steering Control Valve - Adjust SMCS - 4307-025 Note: Adjustments to the steering control valve should only be performed after you complete the procedure in the following reference. Reference: For the correct procedure to check steering timing, refer to the Service Manual module for Testing and Adjusting, "Steering Time - Check" for the machine that is being serviced. Ver imagen

Illustration 1 Steering control valve for machines with conventional steering (1) End cov er. (2) Flow balance shims. (3) Selector valve. (4) Directional co ntrol v alve. (5) Flow control o rifice.

Ver imagen

g00317146

Illustration 2

g00698989

Steering control valve for machines with command control steering (1) End cov er. (2) Flow balance shims.

1. Remove end cover (1) from directional control valve (4) . 2. Add flow balance shims (2) in order to decrease the steering time for a right turn. This causes the machine to steer to the right more quickly. The steering time for a left turn will increase. This causes the machine to steer to the left more slowly. If you remove shims, the results will be the opposite. Use enough shims so that the steering times are nearly identical. Thickness of one new 6J-6516 Shim ... 0.254 mm (0.010 inch) Note: One 6J-6516 Shim changes the steering time at high idle by approximately 0.4 seconds.

Thickness of one new 6J-6517 Shim ... 0.12 mm (0.005 inch) Note: One 6J-6517 Shim changes the steering time at high idle by approximately 0.2 seconds.

3. Install end cover (1) on directional control valve (4) . If both steering times are too slow, the diameter of flow control orifice (5) is too small. Copyright 1993 - 2016 Caterpillar Inc. Todos los derechos reservados. Red privada para licenciados del SIS.





Steering Time - Check SMCS - 4309-531-D7

Ver imagen

Illustration 1

g01103985

Steering Frame Lock in the STORED Position (1) Steering frame lock.

1. Move steering frame lock (1) to the STORED position. 2. Run the engine at high idle. Move the tilt control lever to the TILT BACK position in order to increase the temperature of the oil to normal operating temperature. The oil is at normal operating temperature when the hydraulic oil temperature indicator is between the first mark and the second mark. Note: Do not stall the tilt control lever in the TILT position for more than ten seconds. If necessary, release for ten seconds and repeat the procedure.

3. Park the machine on a surface that is hard, dry, and level.

Ver imagen

Illustration 2

g01041493

Transmission Direction Control Switch

4. Place the transmission direction control switch in the NEUTRAL position. Note: The hydraulic controls should also be in the NEUTRAL position. The parking brake should be disengaged.

5. Articulate the machine to the left or to the right until the machine stops articulating. 6. Run the engine at high idle. Note: Start to measure steering time when you start to turn the steering wheel. Measure steering time until the machine stops articulating.

7. Articulate the machine in the opposite direction until the machine stops articulating. Steering time should be 3.0 ± 0.5 seconds. Note: The difference between the left steering time and the right steering time should not be greater than 0.3 seconds.

8. If the steering time is not within specifications, check the neutral pilot pressure and the piston pump (steering). See the following references. Reference: For the correct procedure to check the neutral pilot pressure, refer to the Service Manual module for Testing and Adjusting, "Pilot Valve (Steering) Supply Pressure - Test and Adjust" for the machine that is being serviced. Reference: For the correct procedure to check the piston pump (steering), refer to the Service Manual module for Testing and Adjusting, "Piston Pump (Steering) Margin Pressure - Test and Adjust" for the machine that is being serviced.

Copyright 1993 - 2016 Caterpillar Inc. Todos los derechos reservados. Red privada para licenciados del SIS.





Command Control Steering - Adjust SMCS - 4343-025


1. Center the machine in the STRAIGHT AHEAD position. 2. Stop the engine. Engage the parking brake.

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Illustration 1

g01104145

Steering Frame Lock in the LOCKED position (1) Steering frame lock.

3. Install steering frame lock (1) in order to prevent machine articulation.

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Illustration 2

g01102335

Steering components (2) Flange. (3) Steering wheel. (4) Steering shaft. (5) Key. (6) Shaft. (7) Pilot co ntrol v alve. (8) Lever. (9) Bolt.

Note: If steering wheel (3) is not in the STRAIGHT AHEAD position, steering wheel (3) must be removed and aligned with key (5). When the components are correctly aligned, the steering wheel will turn evenly to the right and to the left. Ver imagen

Illustration 3

g01102337

4. Remove bolts (10), washers and nuts (11) . 5. Separate flange (2) and lever (8) .

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Illustration 4

g01102339

(5) Key. (6) Shaft. (8) Lever. (9) Bolt. (A) 6.0 ± 1.0 mm (0.25 ± 0.05 inch).

6. Verify that lever (8) and shaft (6) are properly assembled. Dimension (A) should be equal to 6.0 ± 1.0 mm (0.25 ± 0.05 inch). 7. Loosen bolt (9) . 8. Position key (5) in the STRAIGHT AHEAD position. Steering wheel (3) must also be in the STRAIGHT AHEAD position.

Ver imagen

Illustration 5

g01102340

View A-A (2) Flange. (14) Pilot hole.

Note: Be sure that steering wheel (3) is in the STRAIGHT AHEAD position before you perform the following steps.

9. Assemble shaft (6) into pilot hole (14) that is located in flange (2) . 10. Be sure that flange (2) is flush against lever (8) . 11. Attach flange (2) to lever (8) with bolts (10), washers and nuts (11) . 12. Tighten bolt (9) to a torque of 55 ± 10 N·m (40 ± 7 lb ft). Copyright 1993 - 2016 Caterpillar Inc. Todos los derechos reservados. Red privada para licenciados del SIS.





Pilot Valve (Steering) Supply Pressure - Test and Adjust SMCS - 4342-025-PX ; 4342-081-PX




Reference: Refer to Testing and Adjusting, "System Pressure - Release" for the correct procedures for relieving hydraulic oil pressure.

Table 1 Required Tools Part Number

Description

8T-0854

Pressure Gauge (1)

8T-0856

Pressure Gauge (1)

( 1 ) 198-4240 Digital Pressure Indicator is also available.

1. Start the engine. Position the machine so that the machine is pointing straight ahead. 2. Operate the engine at high idle. Move the tilt control lever to the TILT BACK position in order to increase the oil to normal operating temperature. The oil is at normal operating temperature when the hydraulic oil temperature indicator is between the first mark and the second mark. Note: Do not stall the tilt control lever in the TILT position for more than ten seconds. If necessary, release for ten seconds and repeat the procedure.

3. After the oil has reached normal operating temperature, lower work tools to the ground. 4. Stop the engine.

Ver imagen

Illustration 1 Steering frame lock in the LOCKED Position

g01104145

(1) Steering frame lock.

5. Move steering frame lock (1) to the LOCKED position.

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Illustration 2

g01041493

Transmission direction control switch

6. Engage the parking brake. Move the transmission direction control switch to the NEUTRAL position.

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Illustration 3 Location of pilot control valve

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g01098748

Illustration 4

g01042279

Bottom view of pilot control valve (2) Pressure tap for neutral pilot pressure. (3) Supply pressure for the pilot valve. (4) Adjustment screw for the neutral pilot pressure. (5) Locknut.

7. Attach a 0 to 6000 kPa (0 to 870 psi) pressure gauge to pressure tap (3). Pressure tap (3) is located on the rear side of the pilot control valve. Pressure tap (3) is supply pressure for the pilot valve.

NOTICE Bumping or turning the steering wheel could cause excessive oil pressure in the hydraulic oil line that connects to the pressure gauge. The excessive oil pressure could cause damage to the pressure gauge.

Do not bump or turn the steering wheel during the following steps.

8. Attach a 0 to 1000 kPa (0 to 145 psi) pressure gauge to pressure tap (2). Pressure tap (2) is located on the bottom side of the pilot control valve. Pressure tap (2) is for neutral pilot pressure. 9. Start the engine. Run the engine at high idle. 10. Record the pressure reading on the pressure gauge that is attached to pressure tap (3). The reading should equal 3450 ± 250 kPa (500 ± 36 psi). 11. Record the pressure reading on the pressure gauge that is attached to pressure tap (2). The reading should equal 645 ± 15 kPa (93 ± 2 psi). 12. Stop the engine. 13. If the pressure reading for pressure tap (2) is not to specifications, loosen locknut (5). Turn adjustment screw (4) clockwise in order to increase the pressure. Turn adjustment screw (4) counterclockwise in order to decrease the pressure. Note: One turn of adjustment screw (4) will change neutral pilot pressure approximately 100 kPa (15 psi).

14. Repeat Steps 9 through 13 until the correct pressure is achieved on pressure tap (2) . 15. After correct pressure is achieved, hold adjustment screw (4) in place and tighten locknut (5) . 16. If the pressure reading for pressure tap (3) is not to specifications, use the following reference in order to check the pilot pressure for the implement hydraulic system. Reference: For the correct procedure to check the pilot pressure for the implement hydraulic system, refer to the Service Manual module for Testing and Adjusting, "Steering Pilot System Pressure - Test" for the machine that is being serviced. Copyright 1993 - 2016 Caterpillar Inc. Todos los derechos reservados. Red privada para licenciados del SIS.





Steering Pilot System Pressure - Test SMCS - 4300-032-PS






Description

8T-0855

Pressure Gauge (1)


1. Position the machine so that the machine is in the STRAIGHT AHEAD position.

Ver imagen

Illustration 1 Steering frame lock in the LOCKED Position (1) Steering frame lock.


Ver imagen

g01104145

Illustration 2

g01041493

Transmission direction control switch


Ver imagen

Illustration 3 Location of steering control valve and pressure taps

g01098411

Ver imagen

Illustration 4

g01098413

Pressure taps (2) Pressure tap for left pilot pressure.

4. Attach a 0 to 4000 kPa (0 to 580 psi) pressure gauge to pressure tap (2). Pressure tap (2) is located on the right side of the machine and below the screen group for the steering oil. Pressure tap (2) is pilot pressure for left steering. 5. Start the engine. Operate the engine at high idle. Move the tilt control lever to the TILT BACK position in order to increase the temperature of the oil to normal operating temperature. The oil is at normal operating temperature when the hydraulic oil temperature indicator is between the first mark and the second mark. Note: Do not stall the tilt control lever in the TILT position for more than ten seconds. If necessary, release for ten seconds and repeat the procedure.

6. After the oil has reached normal operating temperature, position the work tool slightly off the ground. Run the engine at low idle. Note: During the following step, do not keep the steering pump at stall condition for more than ten seconds. If necessary, release the steering wheel and wait for 30 seconds before you repeat the step.

7. In order to obtain a reliable pressure reading, turn the steering wheel counterclockwise to the FULLY TURNED position. 8. Record the pressure reading on the pressure gauge. 9. Run the engine at high idle. Repeat Steps 7 and 8. 10. The recorded pressures should not be below 1785 kPa (260 psi). 11. Stop the engine. Lower the work tool to the ground. 12. Relieve the hydraulic oil pressure. Use the reference at the beginning of this procedure to relieve any hydraulic oil pressure. 13. Remove the pressure gauge from pressure tap (2) .

Ver imagen

Illustration 5 Pressure taps (3) Pressure tap for checking right pilot pressure.

g01098443

14. Install the pressure gauge to pressure tap (3). Pressure tap (3) is located on the right side of the machine and below the screen group for the steering oil. 15. Run the engine at low idle. Note: During the following step, do not keep the steering pump at stall condition for more than ten seconds. If necessary, release the steering wheel and wait for 30 seconds before you repeat the step.

16. In order to obtain a reliable pressure reading, turn the steering wheel clockwise to the FULLY TURNED position. 17. Record the pressure reading on the pressure gauge. 18. Run the engine at high idle. Repeat Steps 16 and 17. 19. The recorded pressures should not be below 1785 kPa (260 psi). 20. Stop the engine. Lower the work tool to the ground. 21. Relieve the hydraulic oil pressure. Use the reference at the beginning of this procedure to relieve any hydraulic oil pressure. 22. Remove the pressure gauge from pressure tap (3) . Copyright 1993 - 2016 Caterpillar Inc. Todos los derechos reservados. Red privada para licenciados del SIS.





Relief Valve (Steering Cylinder Crossover) - Test and Adjust SMCS - 4322-025; 4322-081




Ver imagen

Illustration 1

g00294202

1. Install steering frame lock (1) into the LOCKED position, as shown.

Ver imagen

Illustration 2

g01042148

Location of the crossover relief valve (A) Steering control valve for machines that are equipped with conventional steering. (B) Steering control valve for machines that are equipped with command control steering.

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Illustration 3

g01042164

(1) Locknut. (2) Steering Cylinder Crossover Relief Valve. (3) Locknut. (4) Adjusting screw.

2. Remove steering cylinder crossover relief valve (2). The steering cylinder crossover relief valve is located in the steering control valve. The steering control valve is located on the left side of the machine. The steering cylinder crossover relief valve needs to be bench tested. Loosen locknut (1) and remove the valve. 3. The pressure of the relief valve should be 29100 ± 700 kPa (4220 ± 100 psi). Adjust the valve pressure, if necessary. Loosen locknut (3). Turn adjusting screw (4) counterclockwise in order to lower the pressure of the valve. Turn the adjusting screw (4) clockwise in order to increase the pressure of the valve. Tighten locknut (3) after the correct pressure is reached. The valve is faulty if the adjusting screw does not affect the pressure. Replace the valve. 4. Install the relief valve into the steering control valve. The valve should be installed with a torque of 60 ± 7 N·m (44 ± 5 lb ft). Copyright 1993 - 2016 Caterpillar Inc. Todos los derechos reservados. Red privada para licenciados del SIS.





Relief Valve (Pump Backup) - Test and Adjust SMCS - 4322-025; 4322-081






Description

8T-0860

Pressure Gauge

The backup relief valve for the steering system is located on the steering control valve. The backup relief valve controls the pressure in the steering system in case the pressure control section of the steering pump fails. The backup relief valve for the steering system is set to a higher pressure than the maximum system pressure (pump stall pressure). Therefore, the backup relief valve only operates if the control section of the steering pump fails to regulate the pump pressure to 24000 ± 350 kPa (3500 ± 50 psi). Use the following procedure to check the pressure setting for the backup relief valve. Note: The following procedure may require removal of the operator's cab to gain access to the pressure and flow compensator valve for the steering pump.

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Illustration 1

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Steering Frame Lock in the LOCKED Position (1) Steering frame lock.


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Illustration 2

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Illustration 3

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3. Attach a 0 to 40000 kPa (0 to 5800 psi) pressure gauge to pressure tap (2). Pressure tap (2) is located on the steering pump. 4. Start the engine. Operate the engine at high idle. Move the tilt control lever to the TILT BACK position in order to increase the oil to normal operating temperature. The oil is at normal operating temperature when the hydraulic oil temperature indicator is between the first mark and the second mark.

Note: Do not stall the tilt control lever in the TILT position for more than ten seconds. If necessary, release for ten seconds and repeat the procedure.

5. After the oil has reached normal operating temperature, lower the bucket and any attachments to the ground. Stop the engine. Note: The following steps may require removal of the operator's cab in order to gain access to the pressure and flow compensator valve for the steering pump.

6. If you must remove the operator's cab, use the following reference for the correct procedure. Reference: For the correct procedure to remove the operator's cab, refer to the Service Manual module for Disassembly and Assembly, RENR4379, "980G II Wheel Loader Machine Systems", "Cab - Remove".

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Illustration 4

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Pressure and Flow Compensator Valve for the Steering Pump (3) Pressure and flow compensator valve. (4) Adjustment screw for the pressure compensator. (5) Locknut.

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Illustration 5

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Pressure and Flow Compensator Valve (3) Pressure and flow compensator valve. (4) Adjustment screw for the pressure compensator. (5) Locknut. (6) Spring. (7) Pressure compensator spool.

7. Remove the cover from adjustment screw (4). Loosen locknut (5) . Note: Be sure that you count the number of turns in the following step.

8. Turn adjustment screw (4) clockwise until the screw bottoms. Adjustment screw (4) will need to be adjusted once the test for the backup relief valve is completed. 9. Start the engine. Raise the bucket until the bucket is slightly off the ground. Run the engine at high idle. Note: During the following step, do not keep the steering pump at stall condition for more than ten seconds. If necessary, release the steering wheel and wait for 30 seconds before you repeat the step.

10. Turn the steering wheel to the FULLY TURNED position. Continue to hold the steering wheel

in the FULLY TURNED position in order to obtain a reliable pressure reading. 11. Record the pressure reading on the pressure gauge. The pressure reading should be 27600 ± 700 kPa (4000 ± 100 psi). 12. Lower the bucket and any attachments to the ground. Stop the engine. 13. If the pressure reading is to specifications, proceed to Step 22. If the pressure reading is not correct, release the steering wheel. Reduce the engine speed to low idle. Stop the engine. Proceed to the next step.

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Illustration 6 Top View of Steering Control Valve (8) Backup relief valve.

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Illustration 7

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Backup Reli ef Valve (10) Adjustment screw. (11) Locknut.

14. Backup relief valve (8) is located on the back end of the steering control valve as you face the right side of the machine. 15. If the pressure reading is not to specifications, loosen locknut (11). To increase the pressure setting, turn adjustment screw (10) clockwise. To decrease the pressure setting, turn adjustment screw (10) counterclockwise. 16. Start the engine. Raise the bucket until the bucket is slightly off the ground. Run the engine at high idle. Note: During the following step, do not keep the steering pump at stall condition for more than ten seconds. If necessary, release the steering wheel and wait for 30 seconds before you repeat the step.

17. Turn the steering wheel to the FULLY TURNED position. Continue to hold the steering wheel in the FULLY TURNED position in order to obtain a reliable pressure reading. 18. Record the pressure reading on the pressure gauge. The pressure reading should be 27600 ± 700 kPa (4000 ± 100 psi). 19. Repeat Steps 15 through 18 until the correct pressure reading is obtained. 20. After adjustment screw (10) is correctly adjusted, tighten locknut (11) to a torque of 13 ± 2 N·m (115 ± 15 lb in). 21. Stop the engine. 22. Use the following procedure to adjust the pressure compensator valve back to the original setting.

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Illustration 8

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Pressure and Flow Compensator Valve (3) Top view of pressure and flow compensator valve. (4) Adjustment screw for the pressure compensator. (5) Locknut. (6) Spring. (7) Pressure compensator spool.

a. Turn adjustment screw (4) counterclockwise for the number of turns that were counted in Step 8. b. Tighten locknut (5) to a torque of 17 ± 3 N·m (150 ± 25 lb in). c. Start the engine and run the engine at high idle. Turn the steering wheel all the way in one

direction. The pressure reading should equal 24000 ± 350 kPa (3500 ± 50 psi). d. Record the pressure reading on the pressure gauge. e. If the pressure reading is to specifications, proceed to Step 23. If the pressure reading is not to specifications, release the steering wheel. Reduce the engine speed to low idle. Stop the engine. f. Turn adjustment screw (4) clockwise in order to increase the pressure setting. Turn adjustment screw (4) counterclockwise in order to decrease the pressure setting. One turn of adjustment screw (4) will change steering system pressure approximately 2790 kPa (405 psi). g. After you turn adjustment screw (4), tighten locknut (5) to a torque of 17 ± 3 N·m (150 ± 25 lb in). h. Start the engine and run the engine at high idle. Turn the steering wheel all the way in one direction. i. Record the pressure reading on the pressure gauge. The pressure reading should equal 24000 ± 350 kPa (3500 ± 50 psi). j. Repeat Steps 22.f though 22.i until you obtain the correct pressure. 23. Lower the bucket and any attachments to the ground. Stop the engine. 24. Remove the pressure gauge from pressure tap (2) . 25. Replace the cover on adjustment screw (4) . 26. If you removed the operator's cab in Step 6, see the following reference. Reference: For the correct procedure to install the operator's cab, refer to the Service Manual module for Disassembly and Assembly, RENR4379, "980G II Wheel Loader Machine Systems", "Cab - Install". Copyright 1993 - 2016 Caterpillar Inc. Todos los derechos reservados. Red privada para licenciados del SIS.





Piston Pump (Steering) Margin Pressure - Test and Adjust SMCS - 4306-081-PX ; 5070-081-PX ; 5086-025-ZH Número de pieza S/N - AXG1-UP Read Testing and Adjusting, "Machine Preparation for Troubleshooting" and understand Testing and Adjusting, "Machine Preparation for Troubleshooting" in this manual before performing the following procedure. This method involves measuring the margin pressure with a differential pressure gauge while the machine is being articulated. The margin pressure is the difference between the steering pump pressure and the pressure in the load sensing line. The load sensing line connects to the flow compensator valve on the steering pump. Margin pressure must be read during machine articulation. When the machine stops articulating, you are not reading margin pressure.

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Illustration 1

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The pressure taps are located on the steering pump (1) . (2) Pressure tap. (3) Pressure tap for the load sensing oil.

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Illustration 2

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1. Connect the high pressure port (8) of the 1U-5796 Pressure Differential Gauge Group (6) to the quick connect port at the pump discharge port (2). Install a 25000 kPa (3625 psi) pressure gauge (4) at the high pressure port (5) of the 1U-5796 Pressure Differential Gauge Group. Connect the low pressure port (7) of the 1U-5796 Pressure Differential Gauge Group (6) to the quick connect port at the pressure tap (3) of the load sensing line. Note: Two separate 6V-7830 Pressure Gauges can be used in place of the pressure differential gauge. These gauges are tetragauges. The tetragauges are capable of reading pressures from 0 to 40000 kPa (5801.6 psi). Connect one tetragauge to pressure tap (3). Connect the other tetragauge to pressure tap (2) . 2. Start the engine. Hold the bucket in the fully tilted back position while the engine is operating at high idle in order to warm the hydraulic oil. Hold the bucket in the tilted position until the reading on the hydraulic oil temperature gauge is between the first mark and the second mark. Note: Do not stall the bucket in the TILT position for more than ten seconds. If necessary, release for ten seconds and repeat the procedure. 3. Articulate the machine fully and engage the parking brake. Run the engine at high idle. Turn the steering wheel in the opposite direction of articulation. Hold the steering wheel in the fully turned position while the machine is articulating. The needle on the differential pressure gauge will bounce between readings. The needle should stabilize at 2800 ± 100 kPa (406.1 ± 14.5 psi) (steering pump margin pressure). Note: If you are using the tetragauges, the steering pump pressure should be 2800 ± 100 kPa (406.1 ± 14.5 psi) higher than the pressure in the load sensing line. This is the margin pressure. These pressures must be read during the articulation of the machine.

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Illustration 3

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4. Stop the engine. Adjust the flow compensator valve if the pressure was not correct. Loosen locknut (9). Adjust setscrew (10) in order to adjust the setting of the steering pump margin pressure. Turn the setscrew clockwise in order to increase the margin pressure. Turn the setscrew counterclockwise in order to decrease the margin pressure. Reference: Refer to the Service Manual module Testing and Adjusting, "Piston Pump (Steering) Low Pressure Standby - Test and Adjust" for the machine that is being serviced. Note: If the margin pressure is set above the specification, the performance of the steering will become too responsive and jerky. Poor modulation will result. If the margin pressure is set below the specification, the performance of the steering will become sluggish and less responsive. Copyright 1993 - 2016 Caterpillar Inc. Todos los derechos reservados. Red privada para licenciados del SIS.





Piston Pump (Steering) Low Pressure Standby - Test and Adjust SMCS - 4306-081-PX ; 5070-081-PX ; 5086-025-ZH Número de pieza S/N - AXG1-UP



NOTICE Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids. Refer to Special Publication, NENG2500, "Caterpillar Tools and Shop Products Guide" for tools and supplies suitable to collect and contain fluids on Caterpillar products.

Dispose of all fluids according to local regulations and mandates.


Description

Qty

1U-5481

Pressure Gauge Group

1

1U-5482

Pressure Adapter Group

1


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Illustration 1

1. Install the steering frame lock.

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Illustration 2

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2. Engage the parking brake. Move the transmission direction control switch into the NEUTRAL position.

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Illustration 3

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3. Install a 10000 kPa (1450 psi) pressure gauge onto pressure tap (1). The pressure tap is located on the discharge line of the steering pump. 4. Start the engine. Operate the engine at high idle. Move the implement control lever to the LIFT position in order to increase the oil to normal operating temperature. The oil is at normal operating temperature when the hydraulic oil temperature gauge is between the first mark and the second mark.

Note: Do not stall the implement control lever in the LIFT position for more than ten seconds. If necessary, release for ten seconds and repeat the procedure. 5. After the oil has reached normal operating temperature, lower the blade until the blade is slightly off the ground. Run the engine at high idle. 6. Record the pressure reading on the pressure gauge. The pressure reading should not exceed 5200 kPa (750 psi). 7. Stop the engine. Lower the blade and any attachment to the ground. Note: You should not adjust the steering pump only because of the results of this test. If the pressure reading is not correct, perform the test for the margin pressure. If the margin pressure is not correct, you need to adjust the flow compensator valve.

Adjusting the Flow Compensator Valve 1. Lower all attachments to the ground. Shut off the engine. Install the steering frame lock. Move the steering control several times in order to relieve system pressure.

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Illustration 4

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2. Install a 5000 kPa (725 psi) pressure gauge onto pressure tap (1). The pressure tap is located on the discharge line of the steering pump.

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Illustration 5

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3. Flow compensator valve (2) is located on the steering pump. Loosen locknut (3). Turn adjusting screw (4) clockwise in order to increase pressure. Turn adjusting screw (4) counterclockwise in order to decrease pressure. 4. Test the low pressure standby again. If the low pressure standby is correct, shut off the engine. Move the steering control several times in order to remove system pressure. Remove the gauge from the pressure tap. 5. Tighten locknut (3) . Copyright 1993 - 2016 Caterpillar Inc. Todos los derechos reservados. Red privada para licenciados del SIS.





Steering System Pressure (High Pressure Stall) - Test and Adjust SMCS - 4306-081-PX ; 5070-081-PX ; 5086-025-ZH

Read Testing and Adjusting, "Machine Preparation for Troubleshooting" and understand Testing and Adjusting, "Machine Preparation for Troubleshooting" in this manual before you perform the following procedure. Table 1 Required Tools Part Number

Description

8T-0860

Pressure Gauge (1)


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Illustration 1 Steering Frame Lock Link

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1. Install the steering frame lock link.

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Illustration 2

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Location of access panel to pressure taps equipped with 211-1937 Diagnostic Lines Gp

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Illustration 3

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Pressure tap location for steering pump pressure, if equipped with 211-1937 Diagnostic Lines Gp

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Illustration 4

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Pressure tap location for steering pump pressure

2. Install a 0 to 27500 kPa (0 to 4000 psi) pressure gauge at pressure tap (1) . Refer to Illustration 3 and 4 for location of the pressure tap. If equipped with the 211-1937 Diagnostic Lines Gp , the pressure tap is located within the access panel behind the cab. See Illustration 2. 3. Start the engine and run the engine at high idle. 4. Turn the machine against the steering frame lock. This maneuver will cause the steering pump to reach the cutoff pressure. Do not allow the steering pump to remain in the stalled position for more than 10 seconds. 5. Observe the pressure gauge. The steering pump output should be 24000 ± 350 kPa (3480 ± 50 psi). 6. Adjust the pressure compensator valve if the steering system pressure is incorrect.

Adjusting the Pressure Compensator Valve

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Illustration 5

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The pressure compensator valve (5) is located on the top of the steering pump (2) . The pressure compensator valve (5) is the bottom valve. 1. Loosen locknut (4) . Turn the adjustment screw (3) clockwise in order to increase the high pressure stall. Turn the adjustment screw (3) counterclockwise in order to decrease the high pressure stall. One turn of the adjustment screw equals approximately 2800 kPa (406 psi). 2. Hold adjustment screw (3) in place and tighten the locknut (4) . Copyright 1993 - 2016 Caterpillar Inc. Todos los derechos reservados. Red privada para licenciados del SIS.





Pump Performance (Steering) - Test SMCS - 4306-032-QP ; 5070-032-ZH

The following procedure should be used in order to help determine if there is a problem with the steering pump. Pump performance should be checked if the machine has slow steering times.

Machine Preparation 1. Move the machine to a smooth horizontal location. Move away from working machines and personnel. Lower the attachments to the ground. 2. Allow only one operator on the machine. Keep all personnel away from the machine or in the view of the operator. 3. Engage the parking brake.

Performance Test Steering Cycle Time The steering time is affected by the amount of oil flow that is produced by the steering pump. Check the steering times in order to determine if there is a problem with the steering pump. 1. Perform the machine preparation for testing. 2. Warm the hydraulic oil to normal operating temperature. Raise the bucket slightly off the ground. 3. Maintain the engine speed at high idle. 4. Record the steering time from stop to stop. The steering time should be 3.0 ± .05 seconds at high idle. 5. Lower the boom and place the bucket flat on the ground. 6. Reduce engine speed to low idle. 7. Stop the engine. Compare the test results with the cycle times that are listed. The steering pump should be working properly if the cycle times match the cycle times that are listed.

If the cycle times are not correct one of the following conditions may be present: The pressure setting for the backup relief valve is not within specifications. The pump is not upstroking. The pump may have excessive wear. The main relief pressure should be measured. If the main relief pressure is low, the cycle times should be retested after the main relief pressure has been corrected. Reference: For more information on testing and adjusting the main relief valve, refer to the Service Manual module Testing and Adjusting, "Relief Valve (Pump Backup) - Test and Adjust" for the machine that is being serviced.

Test the pressure of the steering pump in order to make sure that the pump is upstroking. Reference: For more information on testing and adjusting the steering pump, refer to the Service Manual module Testing and Adjusting, "Steering System Pressure (High Pressure Stall) - Test and Adjust" for the machine that is being serviced.

If the cycle time is slow for only one of the steering circuits, the circuit with slow cycle time should be tested for one of the following conditions: Low relief valve setting Leak in the circuit Control spool that is not shifting fully Flow balance shims may need to be adjusted if the steering times are consistently slow in one direction. Reference: For more information on testing and adjusting the main relief valve, refer to the Service Manual module Testing and Adjusting, "Steering Time - Check and Adjust" for the machine that is being serviced. Copyright 1993 - 2016 Caterpillar Inc. Todos los derechos reservados. Red privada para licenciados del SIS.





Hydraulic Oil Contamination - Test SMCS - 4300-008


Sudden movement or accidental starting of the machine can cause personal injury or death to persons on or near the machine. To prevent personal injury or death, perform the following: Park the machine on a smooth, level surface. Lower the work tool to the ground and engage the parking brake. Stop the engine and remove the key. Block the wheels and install the steering frame lock.

NOTICE Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids. Refer to Special Publication, NENG2500, "Caterpillar Tools and Shop Products Guide" for tools and supplies suitable to collect and contain fluids on Caterpillar products.

Dispose of all fluids according to local regulations and mandates.

The hydraulic oil in this system is SAE 10. If the oil becomes contaminated, premature component failure could result. Contaminated oil can also contribute to overheating. Use the following procedure to sample the oil in the steering system. 1. Start the engine and run the engine at high idle. Allow the oil temperature to reach the normal operating temperature. 2. Actuate all cylinders through a minimum of ten full cycles. 3. Lower the bucket and any attachments to the ground. 4. Stop the engine. 5. Move all control levers and brake pedals through all positions in order to release any pressure in the hydraulic system.

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Illustration 1

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Breaker Relief Valve RH Side of Hydraulic Tank

6. In order to relieve all of the pressure in the hydraulic oil tank, press and hold down plunger (1) on the breaker relief valve.

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Illustration 2

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Fluid Sampling Valve

Note: The oil sampling port is located on the left side of the machine behind the hydraulic tank. In order to access the oil sampling port, the hood for the engine must be raised.

7. Purge the hydraulic oil sampling port (2). Insert an 8T-9208 Probe Assembly into hydraulic oil sampling port (2) . Note: Use approximately 150 mm (6 inch) length of tube on the end of the probe. Drain approximately 100 mL (4 fl oz) of oil into a container for disposal. This will clean out the sampling port so that a good oil sample may be obtained. Reference: Refer to Special Publication, PEHP6001, "How To Take A Good Oil Sample" for more information about obtaining an oil sample.

8. Start the engine and allow the engine to run at low idle. Note: Do not operate the hydraulic controls.

9. Draw a 50 mL oil sample through the fluid sampling port. The level of contaminants must be lower than the values in the following table. Table 1 Hydraulic Oil Contamination ISO Code

Particle Size (Microns)

Maximum Number of Particles Per 1 mL Sample

18

5

2500

15

15

320

Note: The concentration of the particles by size should be monitored over a series of samples. This information can be used in order to spot abnormal wear before a failure occurs. A spectrographic analysis of the samples can be used in order to identify the composition of the particles. The analysis of the oil sample may be used in order to identify the components that are failing. Copyright 1993 - 2016 Caterpillar Inc. Todos los derechos reservados.


Red privada para licenciados del SIS.




System Pressure - Release SMCS - 4300-553-PX

Personal injury can result from hydraulic oil pressure and hot oil. Hydraulic oil pressure can remain in the hydraulic system after the engine has been stopped. Serious injury can be caused if this pressure is not released before any service is done on the hydraulic system. Make sure all of the work tools have been lowered to the ground, and the oil is cool before removing any components or lines. Remove the oil filler cap only when the engine is stopped, and the filler cap is cool enough to touch with your bare hand.

Escaping fluid under pressure, even a pinhole size leak, can penetrate body tissue, causing serious injury, and possible death. If fluid is injected into your skin, it must be treated immediately by a doctor familiar with this type of injury. Always use a board or cardboard when checking for a leak.


Machine Preparation 1. Park the machine on a smooth, level surface. The location should also be dry and free of debris. Turn the engine start switch to the OFF position. 2. Permit only one operator on the machine. All other personnel should be kept away from the machine. 3. Lower the work tool to the ground. 4. Engage the parking brake. 5. Ensure that the engine start switch is in the OFF position.

Release System Pressure 1. Depress the brake pedal repeatedly. This will relieve any pressure that may be present in the braking system. 2. If the machine is equipped with electrohydraulic controls, turn the key start switch to the ON position. Move the implement control levers several times through the full range of travel. This will relieve any pressure that may be present in the implement hydraulic system. Turn the key start switch to the OFF position. 3. Turn the steering wheel several times in both directions in order to relieve the pressure in the steering system.

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Illustration 1

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4. Push in the plunger for the breaker relief valve until all pressure is released. The breaker relief valve is located on the front side of the hydraulic tank.

SISTEMA DIRECCION CARGADOR 980G II.pdf

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