Testing And Adjusting Hydraulic System

Usage:

Introduction

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Hydraulic oil pressure can remain in the hydraulic systems on this machine after the engine and pump have been stopped. Serious injury can be caused if this pressure is not released before any service is done on the hydraulic systems. To prevent possible injury, refer to section, Release Of Pressure In The Hydraulic System, before any fitting, hose or component is loosened, tightened, removed or adjusted.
When possible, the bucket must always be lowered to the ground before service is started. When it is necessary for the boom to be in the raised position while tests or adjustments are done, be sure that boom, stick and bucket have correct support.
Swing lock must be engaged before service is started.

Always move the machine to a location away from the travel of other machines. Be sure that other personnel are not near the machine when the engine is running and tests or adjustments are being made.

During diagnosis of the hydraulic system, remember that correct oil temperature, flow, and pressure are necessary for correct operation. Pump output (oil flow) is a function of engine speed (rpm). Oil pressure is caused by resistance to the flow of oil.

Introduction

NOTE: This manual is divided into the following three main sections:

1. Electronic System Testing And Adjusting

2. Checking Procedures

3. Hydraulic System Testing And Adjusting

NOTE: As a general rule, if there is a doubt as to the cause of a problem, the electronic system should be checked first.

Reference: For information on Systems Operation of the above, make reference to: "Systems Operation, Electronic And Electrical Systems", Form No. SENR5404 and/or "Systems Operation, Hydraulic System", Form No. SENR5495.

This manual contains information on the troubleshooting procedures of the electronic control and hydraulic systems in the 330, 330 L, and 330 LN Excavators. For troubleshooting the engine components, refer to the module Systems Operation, Testing And Adjusting, Basic Engine Components 3306 Engine, Form No. SENR2057.

Visual Checks

A visual inspection of the system is the first step when troubleshooting a problem. Make the inspection with the engine off and the implements lowered to the ground.

1. Check the level of the oil in the hydraulic tank. Slowly loosen the hydraulic tank air vent plug and release the pressure before the filler cap is removed.

2. Remove the filter element and check it for material that would give an indication of damage to a component.

3. Inspect all lines and connections for damage or leaks.

4. Inspect control linkage for bent, broken, or damaged components.

Checks During Operation

The checks during operation can be used to find leakage in the system. They can also be used to find a valve, pump, motor, or cylinder that is not working correctly. The speed of rod movement or the torque on a motor can be used to check the condition of the cylinders, motors, and pumps.

Operational Tests

NOTE: For specifications given in "Operational Tests", a "NEW" specification is the performance that can be expected for a new machine. A "REBUILD" specification is the performance target to use after rebuilding the components of a system. A machine that performs beyond "SERVICE LIMIT" specifications should be checked for improper maintenance or adjustment, component wear, or failure.

Specifications given in charts for a machine equipped with 6500 mm (21 ft 4 in) boom, 3300 mm (10 ft 10 in) stick, and SAE 1.4 m³ (1-3/4 yd³) bucket.

NOTE: The power mode selector switch must be placed at Mode III position, unless otherwise specified, during tests.

Operational Test Preparations

1. Engine speed:

Excavator with no load at high idle, 1850 ± 50 rpm

2. Hydraulic oil temperature: 55 ± 5°C (131 ± 9°F)

NOTE: Fully move the stick in and out several times until the normal hydraulic oil temperature is reached.

3. Relief valve pressure settings are set according to specification.

Reference: Make reference to the section in this module "Relief Valves", "Specifications".

Travel Test On Level Ground

Test Preparation:

1. Set engine speed and increase the hydraulic oil to normal operating temperature.

Reference: Make reference to the section "Operation Tests Preparation"

2. Travel test ground must be hard and as level as possible, and at least 25 m (82.5 ft) long.

4. Draw a 25 m (82.5 ft) straight line on travel test ground as a reference line.

5. Position the machine so that one track is in line (parallel) with the reference line. Put the machine in the travel test position as shown in the illustration.

6. The bucket must be empty.

Test Procedure:

1. Start the engine and place the power mode selector switch in mode III position. Place the engine speed dial at position "10" and the travel speed switch in HIGH (rabbit) position. Move the machine by operating both travel levers at the same time.

2. The first 5 m (16.5 ft) are for a preliminary run. Measure the time required for the machine to travel the remaining 20 m (66 ft) in each direction (FORWARD and REVERSE).

3. Measure the travel deviation from the reference line.

4. Repeat the above procedure with the travel speed switch in LOW (turtle) position.

NOTE: The following chart represents the time (in seconds) it should take to complete the 20 m (66 ft) test run:

NOTE: The following chart represents the travel deviation from the reference line:

Travel On Level Ground (Optional Test)

NOTE: If suitable ground (as stated in Step No.2 in "Test Preparation" for "Travel On Level Ground") cannot be found, the following test should be done as a substitute.

Test Preparation:

1. Set engine speed and increase the hydraulic oil to normal operating temperature.

Reference: Make reference to the section "Operation Tests Preparation"

2. Place the machine on level ground.

3. Raise a track for the test as shown in the illustration.

4. Put a mark on a shoe of the raised track.

Test Procedure:

1. Start the engine and place the power mode selector switch in power Mode III position. Run the raised track with the engine speed dial at position "10" (high idle) and the travel speed switch in HIGH (rabbit) position.

2. Measure the time required for the track to make three complete turns (revolutions) in each direction (FORWARD and REVERSE).

3. Repeat the above procedure with the travel speed switch in LOW (turtle) position.

Drift On Slope

Measuring the amount of drift of the machine on a slope will determine if there is a need to check the travel brake.

Test Preparation:

1. Place the machine on a slope of 12°. The slope surface must be hard and smooth.

2. Put the implements in the position shown in the illustration.

3. Bucket should be empty.

Test Procedure:

1. Put marks on both track and ground to indicate its relative position to the slope.

2. Stop the engine and time three minutes (using a stopwatch).

3. Measure (with a scale) the distance the tracks have moved on the slope.

Swing Speed And Over Swing (On Level Ground)

Measuring the swing speed and over swing of the machine will determine if there is a need to check the swing motor and/or anti-reaction valve.

Test Preparation:

1. Set engine speed and increase the hydraulic oil to normal operating temperature.

Reference: Make reference to the section "Operation Tests Preparation"

2. Place the machine on level ground as shown in the illustration.

3. Put marks on both inner and outer races of the swing bearing to indicate relation of two positions.

4. The bucket should be empty.

Test Procedure (Over Swing):

1. Start the engine and place the power mode selector switch in power Mode III position. Place the engine speed dial at position "10" (high idle).

2. Move the swing control lever to the RIGHT or LEFT until the machine completes a 360° swing operation. Return the swing control lever to the NEUTRAL position at the end of the 360° swing operation and measure the amount of over swing by measuring the distance between the marks on the swing bearing.

NOTE: Use a reference point that is visible from the operator's seat as a indicator of when to stop the 360° rotation.

Test Procedure (Speed):

1. Move the swing control lever to the LEFT or RIGHT and measure the time it takes to complete a 180° swing operation.

Swing Speed And Drift (On A Slope)

Measuring the swing speed on a slope will determine if there is a need to check the swing motor and/or anti-reaction valve. Measuring the swing drift on a slope will determine if there is a need to check the swing parking brake.

Test Preparation:

1. Place the machine on a 12° slope.

2. Place the implements at maximum reach and fill the bucket with soil. The bucket should be positioned above the ground to clear any obstructions.

Test Procedure (Speed):

1. Stop the machine on a slope of 12°. Place the upper structure at a 90° angle to the lower structure as shown in the illustration.

2. Measure the time needed to swing the upper structure 90° counterclockwise. Do the same for a 90° swing clockwise.

Test Procedure (Drift):

1. Stop the machine on a slope of 12°.

2. Place the upper structure at a 90° angle to the tracks as shown in the illustration.

3. Put marks on the inner and outer races of the swing bearing.

4. Stop the engine.

5. Leave the machine in this position for three minutes, and measure swing drift on the circumference of the swing bearing.

6. Rotate the upper structure 180° from the original position as described in Step 1.

7. Repeat Steps 2 through 5.

Test Procedure (Drift):

1. Stop the machine on a slope of 12°.

2. Place the upper structure at a 90° angle to the tracks as shown in the illustration.

3. Put marks on the inner and outer races of the swing bearing.

4. Stop the engine.

5. Leave the machine in this position for three minutes, and measure swing drift on the circumference of the swing bearing.

6. Rotate the upper structure 180° from the original position as described in Step 1.

7. Repeat Steps 2 through 5.

Cylinder Drift

Test Preparation:

1. Set engine speed and increase the hydraulic oil to normal operating temperature.

Reference: Make reference to the section "Operation Tests Preparation"

2. Place the machine on level ground as shown in the illustration.

3. Fill the bucket with soil.

Test Procedure (For Boom And Stick Cylinders):

1. Fully extend the bucket cylinder.

2. Fully retract the stick cylinder.

3. Raise the boom until its upper surface becomes parallel to the ground.

4. Measure each cylinder's length from pin to pin.

5. Stop the engine.

6. Leave the machine in this position for three minutes, then measure each cylinder's length from pin to pin for drift.

Test Procedure (For Bucket Cylinder):

1. Fully extend the bucket cylinder.

2. Raise the boom high enough until the stick is perpendicular to the ground.

3. Measure each cylinder's length from pin to pin.

4. Stop the engine.

5. Leave the machine in this position for three minutes, then measure each cylinder's length from pin to pin for drift.

Cylinder Operating Speed

Test Preparation:

1. Place the machine on level ground.

2. Bucket must be empty.

Test Procedure (Boom Cylinders):

1. Fully retract bucket and stick cylinders.

Extension test;

Measure the time required for the boom cylinders to reach full extension position starting with the bucket on the ground.

Retraction test;

Measure the time required for the bucket to come in contact with the ground from the full extension position of the boom cylinders.

Test Procedure (Stick Cylinder):

1. Position the upper surface of the boom parallel to the ground and fully extend the bucket cylinder.

Extension test;

Measure the time required for the stick cylinder to reach full extension position from full retraction position.

Retraction test;

Measure the time required for the stick cylinder to reach full retraction position from full extension position.

Test Procedure (Bucket Cylinder):

1. Position the upper surface of the boom parallel and the stick perpendicular to the ground.

Extension test;

Measure the time required for the bucket cylinder to reach full extension position from full retraction position.

Retraction test;

Measure the time required for the bucket cylinder to reach full retraction position from full extension position.

Release Of Pressure In The Hydraulic System

Release the pressure in the implement hydraulic circuits (boom, stick, and bucket) before any hydraulic lines or components are disconnected or removed.

1. Fully retract the stick cylinder rod.

2. Adjust the position of the bucket so that it will be flat on the ground when the boom is lowered.

3. Lower the boom until the bucket is flat on the ground.

4. Shut off the engine and put the hydraulic activation control lever in the UNLOCK position.

5. Move the control levers for boom, stick, and swing to all full stroke positions. This will release any pressure that might be present in the pilot system.

6. Slowly loosen the air vent plug on the hydraulic tank and release the pressure.

7. Tighten the air vent plug on the hydraulic tank.

8. The pressure in the hydraulic system has been released and lines and components can be removed.

Pressure Adjustment

Specifications

NOTE: A new or rebuilt machine must perform according to NEW or REBUILD specifications. A machine that performs beyond SERVICE LIMIT specifications must be checked for improper adjustment, wear, or damage of relief valves or pumps.

Adjustment Procedures

NOTE: Values given above are approximate. Use a pressure gauge for adjustment.

Relief Valve Adjustment Preparation

Pump Compartment
(1) Tap (power shift pressure). (2) Tap (upper pump). (3) Tap (lower pump).

1. Place the machine on level ground and stop the engine.

2. Release the pressure in the hydraulic system. See the section, "Release Of Pressure In The Hydraulic System".

3. Connect a 49 000 kPa (7100 psi) pressure gauge to either the main pump tap (2) or tap (3).

4. Connect a 4900 kPa (700 psi) pressure gauge to tap (1).

5. Start the engine and move the stick IN and OUT to its full travel position. Do this operation several times until the hydraulic oil temperature reaches 55 ± 5°C (131 ± 9°F).

6. Place the power mode selector switch in Mode III position.

7. Place the engine speed dial at position "10". Check that engine speed under no load is at 1850 ± 50 rpm with AEC switch in the OFF position. (Read rpm 3 seconds after the speed dial switch has been placed in position "10".)

NOTE: See the section, "Operational Test Preparations" for the specified engine rpm for dial position "10".

NOTE: Normal operations (see characteristic curve) of the engine and pumps are necessary for the pressure adjustment. If the results of the pressure adjustment are not correct, then the engine and pump characteristic curve needs to be checked.

Temporary Setting Of The Main Relief Valve Pressure

NOTE: The purpose for "Temporary Setting Of The Main Relief Pressure" is done so implement line relief valves and travel relief valves can be adjusted.

Top Of Main Control Valves
(4) Plunger. (5) Locknut. (6) Adjuster. (7) Locknut. (8) Main relief valve.

1. Slowly move the bucket control lever to the bucket open position (full cylinder rod retraction).

2. Check to be sure the main relief valve pressure setting is 31 400 ± 490 kPa (4550 ± 72 psi).

NOTE: Always make final pressure adjustments on pressure rise.

3. Loosen locknut (5) and turn plunger (4) clockwise until it bottoms out. Tighten locknut (5).

4. Loosen locknut (7) and turn adjuster (6) clockwise a quarter turn. Tighten locknut (7).

Adjustment Of Line Relief Valve Pressure

Preparation

1. Start the service program "Calibration Mode" and keep the power shift pressure constant at 2250 kPa (325 psi). Read the pressure gauge attached at tap (1) to monitor the power shift pressure.

NOTE: For further information of "Calibration Mode", see the section in this module "Calibration Mode".

NOTE: During line relief adjustment, do not turn the engine OFF to prevent a change in power shift pressure.

2. Use the pressure gauge at tap (2) to read the line relief pressure for boom and bucket circuits. Use the pressure gauge at tap (3) to read the line relief pressure for stick circuit. For line relief pressure settings for the implement circuits see the section, "Pressure Adjustment, Specifications".

NOTE: After adjustment of the line relief valves, return the main relief pressure to its normal setting.

Main Control Valve Compartment (Viewed From Machine Front)
(9) Line relief valve (bucket cylinder head end). (10) Line relief valve (stick cylinder head end).

NOTE: Rod end line relief valves of boom, stick, and bucket are located under the main control valves.

Right Front Of Swing Motor
(11) Boom drift reduction valve. (12) Line relief valve (boom cylinder head end).

Line Relief Valve (typical all cylinders)
(13) Locknut. (14) Screw.

Adjustment (Stick Cylinder)

1. To adjust the pressure in the stick cylinder rod end, move the stick control lever to full stick OUT (rod retracted) position. Check the pressure in the stick cylinder rod end at tap (3).

2. Return the stick control lever to the NEUTRAL position. Loosen locknut (13) and turn screw (14) until line relief valve pressure at tap (3) reads 33 800 ± 1470 kPa (4900 ± 215 psi). Turning screw (14) clockwise increases the pressure and turning screw (14) counterclockwise decreases the pressure.

3. To adjust the pressure in the stick cylinder head end, move the stick control lever to full stick IN (rod extended) position. Check the pressure at tap (3).

4. Return the stick control lever to the NEUTRAL position. Adjust the line relief valve pressure in the same manner as the stick rod end.

NOTE: Always make final pressure adjustment on pressure rise.

Adjustment (Bucket Cylinder)

1. To adjust the pressure in the bucket cylinder head end, move the bucket control lever to full bucket CLOSE (rod extended) position. Check the pressure in the bucket cylinder head end at tap (2).

2. Return the bucket control lever to the NEUTRAL position. Adjust the line relief valve pressure in the same manner as described for the stick cylinder.

3. To adjust the pressure in the bucket cylinder rod end, move the bucket control lever to full bucket OPEN (rod retracted) position. Check the pressure at tap (2).

4. Return the bucket control lever to the NEUTRAL position. Adjust the line relief valve pressure to 33 800 ± 1470 kPa (4900 ± 215 psi) using the same procedure as that described for the stick cylinder.

Adjustment (Boom Cylinder)

1. To adjust the pressure in the boom cylinder head end, move the boom control lever to full boom RAISE (rod extended) position. Check the pressure in the boom cylinder head end at tap (2).

2. Return the bucket control lever to the NEUTRAL position. Adjust the line relief valve pressure in the same manner as described for the stick cylinder.

3. To adjust the pressure in the boom cylinder rod end, move the boom control lever to full boom DOWN (rod retracted) position. Check the pressure at tap (2).

4. Return the boom control lever to the NEUTRAL position. Adjust the line relief valve pressure to 33 800 ± 1470 kPa (4900 ± 215 psi) using the same procedure as that described for the stick cylinder.

NOTE: If an appropriate location is not available for full retraction of the boom cylinder, reverse the line relief valves of the head end and rod end by switching the valves. Adjust the pressure of the line relief valve now attached in the head end. Once adjusted, return the respective relief valves to their original positions and cancel the function of the service program "Calibration Mode". Refer to the section in this module, "Calibration Mode Stop Procedure".

Travel Crossover Relief Valve Adjustment

Sprocket (Left Track)
(16) Sprocket. (17) Stopper.

Travel Brake Valve (Left Track)
(18) Screw. (19) Locknut. (20) Crossover relief valve (forward left travel). (21) Crossover relief valve (reverse left travel).

Pump Compartment
(1) Tap (power shift pressure). (2) Tap (upper pump). (3) Tap (lower pump).

Preparation

1. Start Service Program "Calibration Mode" and maintain power shift pressure at 2250 kPa (325 psi). Read the pressure gauge at tap (1) for the power shift pressure settings.

NOTE: During this test, to prevent a change in power shift pressure do not turn the engine start switch to OFF position.

2. Block forward left travel, by putting stopper (17) in position on the gear of sprocket (16), as shown above.

Adjustment Procedure

1. Slowly move the left travel control lever to full FORWARD position and check the pressure of crossover relief valve (20) at tap (3).

2. Return the control lever to the NEUTRAL position and adjust relief valve pressure. To adjust crossover relief valve (20), loosen locknut (19) and turn screw (18) until the pressure gauge at tap (3) reads 36 800 ± 1470 kPa (5350 ± 215 psi).

3. Tighten locknut (19) to a torque of 44 ± 5 N·m (32 ± 4 lb ft).

NOTE: Always make final pressure adjustments on pressure rise.

4. Position stopper (17) to block reverse left travel.

5. Slowly move the left travel control lever to full REVERSE position and check the pressure of crossover relief valve (21) at tap (3). Adjust the pressure of crossover relief valve (21) in the same manner as described for crossover relief valve (20).

6. Adjust the pressure of crossover relief valves of right travel motor in the same manner as described for the left travel motor. Use the pressure gauge at tap (2) to read the pressure.

7. After completion of adjustment, stop the function of the service program "Calibration Mode". Refer to the section "Calibration Mode Stop Procedure".

Swing Motor Relief Valve Pressure Adjustment

Swing Motor Compartment
(22) Relief valve (right swing). (23) Relief valve (left swing). (24) Locknut. (25) Plug.

Preparation

1. Release the pressure in the hydraulic system. See the section, "Release Of Pressure In The Hydraulic System".

2. Attach a 49 000 kPa (7100 psi) pressure gauge to tap (3).

3. Start the engine and place the engine speed dial at position "10" with the power mode selector switch at Mode III position.

4. Increase the hydraulic oil temperature to 55 ± 5°C (131 ± 9°F).

5. Place the swing lock pin in the LOCKED position (if equipped), or engage the swing brake.

Adjustment Procedure

1. Slowly move the swing control lever for a full RIGHT swing operation and check the pressure of relief valve (22).

2. Return the swing control lever to the NEUTRAL position. Loosen locknut (24) and turn plug (25) until line relief valve pressure at tap (3) reads 29 900 ± 980 kPa (4350 ± 140 psi). Turning plug (25) clockwise increases the pressure and turning plug (25) counterclockwise decreases the pressure.

3. To adjust the relief pressure for left swing, slowly move the control lever to a full LEFT swing operation and check the pressure of crossover relief valve (23).

4. Return the swing control lever to the NEUTRAL position. Adjust the relief valve pressure in the same manner as the swing right relief valve.

NOTE: Always make final pressure adjustment on the pressure rise.

Main Relief Valve Adjustment

NOTE: Pressure adjustments to the main relief valve should be done by first adjusting the travel operation of the main relief valve and then adjusting the implement operation of the main relief valve. Any adjustment to the travel operation of the main relief valve will change the pressure setting to the implement operation of the main relief valve.

NOTE: Always make final pressure adjustments on pressure rise.

Top Of Main Control Valves
(4) Plunger. (5) Locknut. (6) Adjuster. (7) Locknut. (8) Main relief valve.

Preparation

1. Release the pressure in the hydraulic system. See the section, "Release Of Pressure In The Hydraulic System".

2. Attach a 49 000 kPa (7100 psi) pressure gauge to tap (3).

3. Start the engine and place the engine speed dial at position "10" with the power mode selector switch at Mode III position.

4. Increase the hydraulic oil temperature to 55 ± 5°C (131 ± 9°F).

Adjustment Procedure (In Travel Operation)

Sprocket (Left Track)
(16) Sprocket. (17) Stopper.

1. Block forward left travel by putting stopper (17) in position on the gear of sprocket (16).

Pump Compartment
(1) Tap (power shift pressure). (2) Tap (upper pump). (3) Tap (lower pump).

2. Slowly move the left travel control lever to full FORWARD position and check main relief valve pressure at tap (3).

3. Return the control lever to the NEUTRAL position.

4. Loosen locknut (7) and turn adjuster (6) until the pressure gauge at tap (3) reads 34 300 ± 490 kPa (5000 ± 72 psi). Tighten locknut (7) to a torque of 59 ± 10 N·m (44 ± 7 lb ft).

Reference: Turning plunger (4) clockwise increases the pressure. Turning plunger (4) counterclockwise decreases the pressure.

NOTE: Always make final pressure adjustments on pressure rise.

Adjustment Procedure (Implement Operation)

1. Slowly move the control lever to full bucket OPEN (bucket cylinder full retraction) position and check the main relief valve pressure at tap (2).

2. Return the control lever to the NEUTRAL position and adjust main relief valve pressure to 31 400 ± 490 kPa (4550 ± 72 psi).

3. To adjust, loosen locknut (5) and turn plunger (4) until the pressure gauge at tap (2) reads 31 400 ± 490 kPa (4550 ± 72 psi). Tighten locknut (5) to a torque of 50 ± 10 N·m (37 ± 7 lb ft).

Reference: Turning plunger (4) clockwise increases the pressure. Turning plunger (4) counterclockwise decreases the pressure.

NOTE: Always make final pressure adjustments on pressure rise.

Pilot Relief Valve Adjustment

Preparation

Pilot Oil Manifold Compartment
(26) Pilot relief valve. (27) Tap. (28) Locknut. (29) Screw.

1. Place the machine on level ground and stop the engine.

2. Release the pressure in the hydraulic system. See the section, "Release Of Pressure In The Hydraulic System".

3. Connect a 49 000 kPa (7100 psi) pressure gauge to either the main pump tap (2) or tap (3).

4. Connect a 4900 kPa (700 psi) pressure gauge to tap (1) and tap (27).

5. Start the engine and move the stick IN and OUT to its full travel position. Do this operation several times until the hydraulic oil temperature reaches 55 ± 5°C (131 ± 9°F).

6. Place the power mode selector switch in Mode III position.

7. Place the engine speed dial at position "10". Check that engine speed under no load is at specified rpm with AEC switch in the OFF position. (Read rpm 3 seconds after the speed dial switch has been placed in position "10".)

NOTE: See the section, "Operational Test Preparations" for the specified engine rpm for dial position "10".

Adjustment Procedure

1. Loosen locknut (28) of pilot relief valve (26).

2. Turn screw (29) until the pressure gauge reads 3450 + 200 - 0 kPa (500 + 39 - 0 psi).

Reference: Turning screw (29) clockwise increases the pressure and turning screw (29) counterclockwise decreases the pressure.

3. Tighten locknut (28) to a torque of 16 ± 1 N·m (12 ± 1 lb ft).

NOTE: Always make final pressure adjustments on pressure rise.

Adjustment Of Automatic Travel Speed Travel Change Valve

Preparation

1. Reset main relief valves. Refer to the section, "Main Relief Valve Adjustment".

2. Release the pressure in the hydraulic system. See the section, "Release Of Pressure In The Hydraulic System".

Pump Compartment
(1) Tap (lower pump).

3. Install 49 000 kPa (7100 psi) pressure gauge at tap (1) of the lower pump.

Pilot Oil Manifold Compartment
(2) Tap.

4. Install 4900 kPa (700 psi) pressure gauge at tap (2) of pilot oil manifold.

Travel Motor (Left Track)
(3) Hose assembly. (4) Tee. (5) Signal line (two speed travel). (6) Elbow (two speed travel port).

5. Disconnect signal line (5) from the travel motor. Install tee (4) (8T8902) on elbow (6) that the signal line was removed from and connect signal line (5) to tee (4). Attach nipple (6V3965) and O-ring seal (3J1907) to tee and install 4900 kPa (700 psi) pressure gauge to the nipple with test hose assembly (6V3014) and coupler assembly (6V4143).

6. Start the engine and raise the hydraulic oil temperature to 55 ± 5°C (131 ± 9°F).

7. Place the power mode selector switch in power Mode III position and maintain the maximum no load speed of 1850 ± 50 rpm with AEC switch OFF.

Sprocket (Left Track)
(7) Sprocket. (8) Stopper.

8. Block the forward left travel by putting stopper (8) in position on the gear of sprocket (7), as shown above.

9. Place the travel speed control switch in HIGH (rabbit) position.

10. The pressure gauge at tap (2) should read 3450 kPa (500 psi).

Adjustment Procedure

Pilot Oil Manifold Compartment
(9) Automatic travel speed change valve. (A) Viewed from (A) side.

Automatic Travel Speed Change Valve (Viewed From A)
(9) Automatic travel speed change valve. (10) Screw. (11) Locknut.

1. While reading the pressure gauges connected to the signal pressure line (5) and at tap (1), slowly move the left travel control lever/pedal to the FORWARD position. When the pressure at tap (1) reads 32 400 ± 980 kPa (4700 ± 140 psi), the pressure gauge connected to signal line (5) should reduce to 0 kPa (0 psi).

NOTE: These pressures indicate that the automatic travel speed change valve has caused the travel motor to shift to LOW (tortoise) speed.

2. Slowly return the left travel control lever/pedal to the NEUTRAL position.

3. If the pressure gauge connected to signal line (5) does not read 0 kPa (0 psi) at the time the system pressure at tap (1) reads 32 400 ± 980 kPa (4700 ± 140 psi), then adjust automatic travel speed change valve (9) as follows:

NOTE: Always make final pressure adjustments on pressure rise.

a. Loosen locknut (11) and turn screw (10) until the pressure gauge connected to line (5) reads 0 kPa (0 psi) when the pressure gauge at tap (1) reads 32 400 ± 980 kPa (4700 ± 140 psi).

b. Tighten locknut (11) to a torque of 16 ± 1 N·m (12 ± 1 lb ft).

NOTE: Turning screw (10) clockwise increases the pressure. Turning screw (10) counterclockwise decreases the pressure.

4. Repeat Step 1.

5. Slowly move the travel control lever/pedal towards the NEUTRAL position until the pressure gauge at tap (1) decreases to 18 600 ± 980 kPa (2700 ± 140 psi). Now the pressure gauge connected to signal line (5) will read 3450 kPa (500 psi).

NOTE: These pressures indicate when the automatic travel speed change valve causes the travel motor to shift to HIGH (rabbit) speed.

Pump Flow Tests

Controller Compartment
(1) Controller alarm lamp. (2) Controller.

Right Console
(3) Monitor. (4) Monitor panel.

NOTE: Before starting pump flow tests, check the action alarm indicators on controller (2) and monitor panel (4). If they indicate normal, then perform the operational tests.

NOTE: If operational tests (for example, cycle times) indicates that a slow implement problem is common to the circuits of one pump, then the problem is most likely in the hydraulic system. Then perform the "Pump Flow Tests".

NOTE: If the operational tests indicate a implement speed problem common to both pump circuits, then the engine, fuel, or working altitude may be the problem.

Main Pump Constant Horsepower Control Test

Illustration Of Flow Meter Tool Layout 1 (Hydraulic Horsepower Control Test) (Main Pumps)
(1) Sleeve. (2) Reusable coupling. (3) O-ring seal. (4) Coupler. (5) Nipple. (6) Elbow. (7) Flange. (8) Hose. (9) Bolt. (10) Washer. (11) Hose. (12) Upper pump. (13) Lower pump. (14) O-ring seal. (15) Delivery line (lower pump). (16) Delivery line (upper pump). (17) Cover. (18) Adapter. (19) O-ring seal. (20) Coupler as. (21) O-ring seal. (22) Swing motor. (23) Tee. (24) Return line. (25) Portable Hydraulic Tester.

Preparation (Upper Pump)

Circuit Diagram For Flow Test (Hydraulic Constant Horsepower Control)(Upper Pump)
(8) Hose. (12) Upper pump. (13) Lower pump. (15) Delivery line (lower pump). (16) Delivery line (upper pump). (17) Cover. (22) Swing motor. (23) Tee. (25) Portable hydraulic tester (flow meter). (26) Main control valves. (28) Gauge. (29) Tap (power shift pressure) (30) Gauge. (31) Multitach.

Pump Compartment
(8) Hose. (11) Hose. (12) Upper pump. (13) Lower pump. (15) Delivery line (lower pump). (16) Delivery line (upper pump). (27) Tap (upper pump). (29) Tap (power shift pressure). (32) Tap (lower pump).

Swing Motor Compartment
(8) Hose. (22) Swing motor. (23) Tee. (24) Return line.

Portable Hydraulic Tester (Flow Meter)
(8) Hose. (25) Portable hydraulic tester (flow meter). (31) Multitach. (33) Valve (flow meter).

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To prevent personal injury or equipment damage from failure of the flow meter or associated circuit components because of blocked pump flow, make sure before starting the engine that the flow meter valve is fully open (turned counterclockwise).

1. Position the machine on level ground and stop the engine.

2. Release the pressure in the hydraulic system. See the section, "Release Of Pressure In The Hydraulic System".

NOTE: The bolts that retain the guard between the pumps and engine may require loosening to provide sufficient clearance to install tooling.

3. Install the following tools in accordance with flow meter tool layout illustration and circuit diagram.

a. Disconnect delivery line (16) from upper pump (12).

b. Install cover (17), O-ring seal (14), flanges (7), bolts (9), and washers (10) to the end of delivery line (16).

c. Disconnect return line (24) from swing motor (22).

d. Install tee (23) and two O-ring seals (21) to the swing motor (22) return port. Connect return line (24) to tee (23) using O-ring seal (21).

e. Connect portable hydraulic tester (25) between upper pump (12) and tee (23) with two hoses (8) and hose (11).

f. Install pressure gauge (30) at power shift pressure tap (29). Install pressure gauge (28) at upper pump tap (27). [A 49 000 kPa (7100 psi) pressure gauge can be used in place of pressure gauge (28) and (30).] Tap (29) is used to measure the power shift pressure. Taps (27) and (32) are used to measure the upper pump and lower pump delivery pressure.

g. Install multitach group (31) on the engine. This is used to read engine speed.

4. Start the engine and place the power mode selector switch in Mode III position.

5. Place the engine speed dial at position "10" and maintain the maximum no load speed at 1850 ± 50 rpm with the AEC switch OFF. (Read the rpm three seconds elapsed time after the engine speed dial has been placed in position "10").

6. Increase the hydraulic oil temperature to 55 ± 5°C (131 ± 9°F). To increase the oil temperature, move the stick IN and OUT its full travel several times.

Preparation (Lower Pump)

Circuit Diagram For Flow Test (Hydraulic Constant Horsepower Control)(Lower Pump)
(8) Hose. (12) Upper pump. (13) Lower pump. (15) Delivery line (lower pump). (16) Delivery line (upper pump). (17) Cover. (22) Swing motor. (23) Tee. (25) Portable hydraulic tester (flow meter). (26) Main control valves. (28) Gauge. (29) Tap (power shift pressure) (30) Gauge. (31) Multitach.

Pump Compartment
(11) Hose. (12) Upper pump. (13) Lower pump. (15) Delivery line (lower pump). (29) Tap (power shift pressure). (32) Tap (lower pump).

Perform the same preparation as that described for the upper pump flow test under constant horsepower control except Step 3. Use the following procedure in replacement for Step 3, for the lower pump (13).

a. Disconnect delivery line (15) from lower pump (13).

b. Install cover (17), O-ring seal (14), flanges (7), bolts (9), and washers (10) to the end of delivery line (15).

c. Disconnect return line (24) from swing motor (22).

d. Install tee (23) and two O-ring seals (21) to the swing motor (22) return port. Connect return line (24) to tee (23).

e. Connect portable hydraulic tester (25) between lower pump (13) and tee (23) with two hoses (8) and hose (11).

f. Install pressure gauge (30) at power shift pressure tap (29). Install pressure gauge (28) at lower pump tap (32). [A 49 000 kPa (7100 psi) pressure gauge can be used in place of pressure gauge (28) and (30).] Tap (30) is used to measure the power shift pressure. Taps (27) and (32) are used to measure the upper pump and lower pump delivery pressure.

g. Install multitach group (31) on the engine. This is used to read engine speed.

Test Procedure

NOTE: Perform the upper and lower pump flow tests one at a time.

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To prevent personal injury and/or equipment damage from failed lines or components while the flow meter is returned to the open flow position after a flow test, slowly open the flow meter valve and monitor pump flow at the same time to make sure flow increases. If pump flow does not increase as the flow meter is opened, shut the engine off and determine what is causing the pump not to upstroke.

1. With the engine running, start the service program "Calibration Mode" and maintain the power shift pressure at a constant pressure of 1330 ± 50 kPa (190 ± 7.5 psi). The power shift pressure is read at tap (29), using pressure gauge (30).

NOTE: During this test, do not turn the starter switch to the OFF position to prevent any change in power shift pressure. See the section in this module "Calibration Mode Stop Procedure".

NOTE: To start service program "Calibration Mode" see the section in this module "Calibration Mode Start-up".

2. Slowly turn valve (33) of portable hydraulic tester (25) clockwise and record pump flow at each of the following pressure points. Use pressure gauge (28) at tap (27) or (32) for this pressure reading.

P-Q Characteristic Curve

NOTE: Flow specifications given above are based on an engine speed of 1800 rpm. To get more accurate test results, each of measurements should be corrected by calculating as follows.

Flow corrected = (Flow measured × 1800) ÷ RPM measured

1. Any flow readings must be done only in upstroke (pressure rise).

2. The pump flow changes approximately 10 liter/min. (2.6 U.S. gpm) for each 100 kPa (14 psi) of power shift pressure.

Negative Flow Control Test

Illustration Of Flow Meter Tool Layout 1 (Negative Flow Control Test) (Main Pump)
(1) Sleeve. (2) Reusable coupling. (3) O-ring seal. (4) Coupler. (5) Nipple. (6) Elbow. (7) Flange. (8) Hose. (9) Bolt. (10) Washer. (11) Hose. (12) Upper pump. (13) Lower pump. (14) O-ring seal. (15) Delivery line (lower pump). (16) Delivery line (upper pump). (17) Cover. (18) Adapter. (19) O-ring seal. (20) Coupler as. (21) O-ring seal. (22) Swing motor. (23) Tee. (24) Return line. (25) Portable Hydraulic Tester.

Preparation (Upper Pump)

Circuit Diagram For Negative Flow Control Test (Upper Pump)
(8) Hose. (12) Upper pump. (13) Lower pump. (15) Delivery line (lower pump). (16) Delivery line (upper pump). (17) Cover. (22) Swing motor. (23) Tee. (25) Portable hydraulic tester (flow meter). (26) Main control valves. (27) Tap (upper pump). (28) Gauge. (29) Tee. (30) Gauge. (31) Multitach. (32) Tap (lower pump). (34) Negative flow control line (upper pump). (35) Negative flow control line (lower pump). (36) Plug. (37) Hose assembly. (38) Pilot oil manifold. (39) Tap.

Pump Compartment
(8) Hose. (11) Hose. (27) Tap (upper pump). (32) Tap (lower pump). (34) Negative flow control line (upper pump). (35) Negative flow control line (lower pump).

Swing Motor Compartment
(8) Hose. (22) Swing motor. (23) Tee. (24) Return line.

Portable Hydraulic Tester (Flow Meter)
(8) Hose. (25) Portable hydraulic tester (flow meter). (31) Multitach. (33) Valve (flow meter).

Pump Compartment
(38) Pilot oil manifold. (39) Tap. (40) Pilot relief valve.

Illustration Of Tool Layout 2 (Negative Flow Control Test) (Main Pump)
(12) Upper pump. (13) Lower pump. (29) Tee. (30) Gauge. (34) Negative flow control line (upper pump). (35) Negative flow control line (lower pump). (36) Plug. (37) Hose assembly. (38) Pilot oil manifold. (39) Tap. (41) Coupler assembly. (42) Nipple. (43) O-ring seal. (44) O-ring seal. (45) Cap.

1. Position the machine on level ground and stop the engine.

2. Release the pressure in the hydraulic system. See the section in this module "Release Of Pressure In The Hydraulic System".

3. Install the following tools in accordance with flow meter tool layout illustrations and circuit diagram.

a. Disconnect delivery line (16) from upper pump (12).

b. Install cover (17), O-ring seal (14), flange (7), bolt (9), and washer (10) to the end of delivery line (16).

c. Disconnect return line (24) from swing motor (22).

d. Install tee (23) and two O-ring seals (21) to the swing motor (22) return port. Connect return line (24) to tee (23) using O-ring seal (21).

e. Connect portable hydraulic tester (25) between upper pump (12) and tee (23) with two hoses (8).

f. Remove negative flow control line (34) from port of upper pump (12) and install plug (36) and O-ring seal (44) in open end of negative flow control line (34).

g. Connect two tees (29) together using and O-ring seal (44). Install one end of the tees to negative flow control line (34) port of upper pump (12). Install nipple (42) and O-ring seal (43) in each tee (29). Connect test hose assembly [thread size: 11/16-16UN, 1 m (3.3 ft) long](37) and two coupler assemblies (41) between nipple (42) on one tee and tap (39) of pilot oil manifold (38).

h. Install 4900 kPa (700 psi) pressure gauge (30) to nipple (42) on the second tee. Install cap (45) and O-ring seal (44) on the open end of second tee (29). Install pressure gauge (28) at upper pump tap (27). [A 49 000 kPa (7100 psi) pressure gauge can be used in place of pressure gauge (28)]. Gauge (30) is used to measure the negative control flow. Gauge (28) is used to measure the upper pump or lower pump delivery pressure.

i. Install multitach group (31) on the engine. This is used to read engine speed.

4. Start the engine and place the power mode selector switch in Mode III position.

6. Increase the hydraulic oil temperature to 55 ± 5°C (131 ± 9°F). To increase the oil temperature, move the stick IN and OUT its full travel several times.

Preparation (Lower Pump)

Circuit Diagram For Negative Flow Control Test (Lower Pump)
(8) Hose. (12) Upper pump. (13) Lower pump. (15) Delivery line (lower pump). (16) Delivery line (upper pump). (17) Cover. (22) Swing motor. (23) Tee. (25) Portable hydraulic tester (flow meter). (26) Main control valves. (27) Tap (upper pump). (28) Gauge. (29) Tee. (30) Gauge. (31) Multitach. (32) Tap (lower pump). (34) Negative flow control line (upper pump). (35) Negative flow control line (lower pump). (36) Plug. (37) Hose assembly. (38) Pilot oil manifold. (39) Tap.

Perform the same preparation as that described for the upper pump negative pump flow control test except Step 3. Use the following procedure in replacement for Step 3, for the lower pump (13).

a. Disconnect delivery line (15) from lower pump (13).

b. Install cover (17), O-ring seal (14), flange (7), bolt (9), and washer (10) to the end of delivery line (15).

c. Disconnect return line (24) from swing motor (22).

d. Install tee (23) and two O-ring seals (21) to the swing motor (22) return port. Connect return line (24) to tee (23) using O-ring seal (21).

e. Connect portable hydraulic tester (25) between lower pump (13) and tee (23) with two hoses (8).

f. Remove negative flow control line (35) from port of lower pump (13) and install plug (36) and O-ring seal (44) in open end of negative flow control line (35).

g. Connect two tees (29) together using and O-ring seal (44). Install one end of the tees to negative flow control line (35) port of lower pump (13). Install nipple (42) and O-ring seal (43) in each tee (29). Connect test hose assembly [thread size: 11/16-16UN, 1 m (3.3 ft) long](37) two coupler assemblies (41) between nipple (42) on one tee and tap (39) of pilot oil manifold (38).

h. Install 4900 kPa (700 psi) pressure gauge (30) to nipple (42) on the second tee. Install cap (45) and O-ring seal (44) on the open end of second tee (29). Install pressure gauge (28) at lower pump tap (32). [A 49 000 kPa (7100 psi) pressure gauge can be used in place of pressure gauge (28)]. Gauge (30) is used to measure the negative control flow. Gauge (28) is used to measure the upper pump or lower pump delivery pressure.

i. Install multitach group (31) on the engine. This is used to read engine speed.

Test Procedure

NOTE: Perform the upper and lower pump negative flow control tests one at a time.

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1. Place the power mode selector switch in the Mode III position.

2. Negative flow control test for the upper and lower pumps must be done one at a time.

3. Slowly turn valve (33) of portable hydraulic tester (25) clockwise until the pump delivery pressure setting is 13 700 kPa (1975 psi).

4. Adjust pilot relief valve (40) of pilot oil manifold (38) until pressure gauge (30) connected to tee (29) reads 2450 kPa (335 psi).

5. Record the negative control flow at the following pressure point.

P-Q Characteristic Curve [Negative Flow Control at 13 700 kPa (1975 psi) Pump Delivery Pressure]

NOTE: Flow specifications given above are based on an engine speed of 1800 rpm. To get more accurate test results, measured flow should be corrected by calculating as follows:

Flow corrected = (Flow measured × 1800) ÷ rpm measured

NOTE: Flow measurements must be taken only in pressure rise.

Pump Flow Adjustment

Pump Output Flow Adjustment

Pump Compartment
(1) Locknut. (2) Setscrew. (3) Locknut. (4) Setscrew.

Output flow adjustment procedure for the upper and lower pumps are the same. Use locknut (1) and setscrew (2) for the upper pump adjustment and locknut (3) and setscrew (4) for the lower pump adjustment.

1. Loosen locknut (1).

2. Turn setscrew (2) until adjusted to the correct specification.

Turning setscrew (2) clockwise increases the flow rate. Turning setscrew (2) counterclockwise decreases the flow rate by the same amount as shown in the clockwise rotation. A quarter turn of setscrew (2) changes the flow rate as follows;

a. Approximately 19 liter/min (5.0 U.S. gpm) at a system pressure of 19 600 kPa (2850 psi) or 21 600 kPa (3150 psi) where the first stage spring in the pump regulator activates.

b. Approximately 7 liter/min (1.9 U.S. gpm) at a system pressure of 27 500 kPa (4000 psi) or 34 300 kPa (5000 psi) where the second stage spring in the pump regulator activates.

3. Tighten locknut (1) to a torque of 12 ± 3 N·m (9 ± 2 lb ft).

4. Perform the same procedure for the lower pump as that described for the upper pump output flow adjustment except use locknut (3) and setscrew (4).

Maximum Pump Flow Adjustment

Pump Compartment
(5) Locknut. (6) Setscrew. (7) Setscrew. (8) Locknut.

Maximum pump flow adjustment procedure for the upper and lower pumps are the same. Use locknut (5) and setscrew (6) for the upper pump adjustment and locknut (7) and setscrew (8) for the lower pump adjustment.

1. Loosen locknut (5).

2. Turn setscrew (6) until adjusted to the correct specification.

Turning setscrew (6) clockwise decreases the flow rate. Turning setscrew (6) counterclockwise increases the flow rate by the same amount as shown in the clockwise rotation. A quarter turn of setscrew (6) changes the flow rate by approximately 1.5 liter/min (0.4 U.S. gpm).

3. Tighten locknut (5) to a torque of 55 ± 10 N·m (41 ± 7 lb ft).

4. Perform the same procedure for the lower pump as that described for the upper pump maximum pump flow adjustment except use locknut (7) and setscrew (8).

Negative Flow Control Adjustment

Pump Compartment
(9) Setscrew. (10) Locknut. (11) Setscrew. (12) Locknut.

Negative flow control adjustment procedure for the upper and lower pumps are the same.

1. Loosen locknut (10).

2. Turn setscrew (9) until adjusted to the correct specification.

Turning setscrew (9) clockwise decreases the flow rate. Turning setscrew (9) counterclockwise increases the flow rate by the same amount as shown in the clockwise rotation. A quarter turn of setscrew (9) changes the flow rate by approximately 5 liter/min (1.3 U.S. gpm) at a system pressure of 2450 kPa (355 psi).

3. Tighten locknut (10) to a torque of 12 ± 3 N·m (9 ± 2 lb ft).

4. Perform the same procedure for the lower pump as that described for the upper pump maximum pump flow adjustment except use locknut (12) and setscrew (11).