Takeuchi Mini Excavator TB215R (No.215000003~). Operator's Manual

Overall machine

TroubleshooTing

5b0AX00

overAll mAchine

2. check the fuse

check the fuse in the power supply circuit that oper-

ates the pilot solenoid valve.

3. check the limit switch

Turn the limit switch on, by moving the lever stand to

the driving position.

Then check the voltage at the lever lock solenoid valve

with a tester.

If there is voltage, the switch works normally.

4. check the lever lock solenoid valve

Check according to the following procedure.

a. Turn the starter switch to the on position.

b. Lightly press down the protruding part on the sole

noid valve.

c. move the lever stand to turn on the limit switch.

d. If you feel vibration under your fingers when the

spool is moved and the circuit is switched, the sole-
noid valve is normal.

5. check the pilot relief valve

measure the relief pressure of the pilot relief valve.

• If the measured value is within specifications, the

valve is normal.

“2. Service data, Performance criteria”

6. check the pilot valve

“4. Disassembly and assembly, Pilot valve”

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Traveling

TroubleshooTing

5c0AX00

TrAveling

Traveling

No travel is possible

check the supply pres-
sure for the travel lever
lock cylinder

normal

Check the linkage

Faulty

repair or replace the faulty

part(s)

normal

check the travel lever lock
cylinder

Faulty

replace the travel lever lock
cylinder

1. check the supply pressure for the travel lever lock

cylinder

Disconnect the piping connecting the solenoid valve

and the travel lever lock cylinder from the cylinder side.

Fit the pressure gauge to the hose just disconnected to

measure the pilot pressure.

• Fit the plug to the cylinder port from which the hose

was disconnected.

• If the measured value is within the specifications, the

pressure is normal.

“2. Service data, Performance criteria”

2. check the linkage

Check the operation of the travel lever lock cylinder (1)

and the slide plate (2).
• Cylinder stroke......10 mm (0.4 in.)
• The operations of the lever lock cylinder and the

slide plate are checked. Also, the fixing bolts and

nuts should be checked for the looseness.

3. The travel lever lock cylinder is faulty

it is not possible to disassemble the travel lever lock

cylinder. replace the cylinder with a new one.

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Traveling

TroubleshooTing

5c0AX00

TrAveling

Right or left travel is impossible

check the operation of
actuators other than of
the travel motor

normal

check the spool opera-
tion

Faulty

Repair or replace the housing

block

normal

Check the linkage

Faulty

Adjust, repair or replace

normal

check the swivel joint

Faulty

repair or replace the swivel
joint

normal

check the counter bal-
ance valve

Faulty

repair or replace the counter
balance valve

normal

check the travel motor

Faulty

repair or replace the travel
motor

1. check the operation of actuators other than of the

travel motor.

If the right or left travel is impossible, operate each ac

tuator of the devices listed in the table on the right.

if operation is faulty, inspect the main relief valve and
piston pump.

2. check the spool operation

• Spool stroke......7 mm (0.3 in.)
• If the spool is sticking, try to take it out.

if it can’t be taken out or is scratched, replace the

housing block.

One cause of the spool not operating properly could

be that the return spring installation bolt is loose.

Problem

lever to

operate

Device to check

relief valve

Pump

Right travel

boom

left travel

Arm

*$)=

Traveling

TroubleshooTing

5c0AX00

TrAveling

3. check the linkage

To check the linkage, remove the R pin (2) and pin (3)

which connect the spool and the yoke (1), and then
inspect the yoke (1) movement.

4. check the swivel joint

• Disconnect the hose connecting the swivel joint and

the counter balance valve from the counter balance

valve. Fit the pressure gauge to the hose just dis

connected.

• Operate the travel lever and measure the pressure.
• If the measured value is within specifications, the

swivel joint is normal.

“2. Service data, Performance criteria”

5. check the counter balance valve

• If neither forward nor reverse travel is possible, the

spool (1) of the counter balance valve could be
sticking in the neutral position.

• If either forward or reverse travel is possible, the

spool (1) of the counter balance valve could be stick

ing in a position other than the neutral position.

• Remove the counter balance valve plug (2) and push

the spool (1) with a finger. If it moves smoothly about
6 mm (0.2 in.), the counter balance valve is normal.

6. check the travel motor

“4. Disassembly and assembly, Travel motor”

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*$)=

Traveling

TroubleshooTing

5c0AX00

TrAveling

Right or left travel speed decelerates, causing the machine to veer to one side

Is the veering within

specs?

Within specs

Problem is caused by the

combination of devices

normal

out-of-specs

check the crawler belt

tension. check for for-

eign matter caught in the

crawler belt

Faulty

Adjust to the specified crawler
tension and remove the for-

eign matter

normal

check the spool opera-
tion

Faulty

Repair or replace the housing

block

normal

Switch the discharge hos

es between the pumps

Veering is changed to the opposite

side

•

repair or replace the pumps

•

replace the hydraulic oil or
the filter

No change

Test by switching the main

relief valves

Veering is changed

to the opposite side check the main relief

valve

repair or replace the faulty
main relief valve

No change

check the swivel joint

Faulty

repair or replace the swivel
joint

normal

check the counter bal-
ance valve

Faulty

repair or replace the counter
balance valve

normal

Travel motor is faulty

repair or replace the travel
motor

Traveling

TroubleshooTing

5c0AX00

TrAveling

1. is the veering within specs?

If the veering is within specifications, the machine is

normal. Problem is caused by the combination of de

vices.

“2. Service data, Performance criteria”

2. check the crawler tension

“2. Service data, Performance criteria”

3. check the spool operation

“No travel is possible, 2. Check the linkage.”

4. Switch the discharge hoses between the pumps

Switch the discharge hoses between the pumps P1

and P2. If the veering direction is changed to the op

posite side, the pumps are faulty.

• Disassemble and check the pump

“4. Disassembly and assembly, hydraulic pump”

5. Test by switching the main relief valves

Switch the main relief valves between the right travel

circuit and the left travel circuit, and operate the ma-

chine. If the veering is changed to the opposite side,

one of the main relief valves is faulty.

• Check the main relief valve

“5. Troubleshooting, Overall machine, All sys

tems working, but insufficient force, 4. Check

the main relief valve.”

6. check the swivel joint

“Right or left travel is impossible, 4. Check the

swivel joint”

7. check the counter balance valve

check to see if the spool of the counter balance valve

moves smoothly.

“Right or left travel is impossible, 5. Check the

counter balance valve”

8. check the travel motor

“4. Disassembly and assembly, Travel motor”

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Traveling

TroubleshooTing

5c0AX00

TrAveling

2nd speed travel is not possible

Check the gear pump (4)

Faulty

Repair or replace the gear

pump

normal

check the fuse

Faulty

replace the fuse

normal

check the 2nd speed
switch, harness and con-
troller

Faulty

replace the 2nd speed switch,
harness and controller

normal

check the 2nd speed so-
lenoid valve

Faulty

repair or replace the 2nd
speed solenoid valve

normal

check the swivel joint

Faulty

repair or replace the swivel
joint

normal

check the 2nd speed
control valve

Faulty

repair or replace the 2nd
speed control valve

1. check the gear pump (4)

Check the gear pump (4) that supplies hydraulic pres

sure for the 2nd speed switching.

“2. Service data, Performance criteria”
“5. Troubleshooting, Piston pump”

Also, check the line filter for clogging, and clean it as

necessary.

2. check the fuse

check the fuse in the power supply circuit that acti-

vates the 2nd speed solenoid valve.

Traveling

TroubleshooTing

5c0AX00

TrAveling

3. check the 2nd speed switch, harness and control-

ler

a. Press the switch to turn it on. Use a tester to check

if a voltage is applied.

The switch is normal if a voltage is applied.

b. check the harness continuity.
c. check the switch.
d. check the controller.

“2. Service data, Electric circuit diagram”

4. check the 2nd speed solenoid valve

a. Turn the starter switch to the on position.

b. Lightly press down the protruding part on the sole

noid end.

c. move the lever stand to turn on the limit switch.

d. If you feel vibration under your fingers when the

spool is moved and the circuit is switched, the sole-
noid valve is normal.

5. check the swivel joint

Disconnect the hose connecting the swivel joint and

the 2nd speed control valve from the 2nd speed con-

trol valve. Fit the pressure gauge to the hose just dis

connected, and then turn on the 2nd speed switch.

• Supply pressure: 3.4 MPa (493 PSI)

6. 2nd speed control valve is faulty

check if the spool of the 2nd speed control valve is

sticking or if foreign matter is caught in the spool.

“4. Disassembly and assembly, Travel motor”

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5C0AQ03Z

Slewing

TroubleshooTing

5D0AX00

sleWing

Slewing

No slewing is possible

check the operation of
actuators other than of
the slew motor

normal

check the pilot valve

Faulty

repair or replace the pilot
valve

normal

check the spool opera-
tion

Faulty

Repair or replace the housing

block

normal

check the slew pressure

Pressure too low

Adjust the pressure of the
slew relief valve

Adjust to the set pressure

normal

Pressure does not rise

repair or replace the relief
valve

check the slew motor

Faulty

repair or replace the slew
motor

normal

Slew bearing is faulty

replace

1. check the operation of actuators other than of the

slew motor

Determine if only the slew motor is faulty by checking

the operation of actuators for the devices listed in the

table on the right. If one of them is faulty, check the
main relief valve and the hydraulic pump (main).

“5. Troubleshooting, Overall machine, All systems

working, but insufficient force”

lever to operate

Device to check

relief valve

Pump

blade

Slewing

TroubleshooTing

5D0AX00

sleWing

2. check the pilot valve

Disconnect the hose connecting the pilot valve and the

control valve (slew block) from the control valve. Fit the
pressure gauge to the hose just disconnected.
•  Insert a plug into the control valve port.
•  Operate the lever (slew) and measure the pressure.
•  If the pressure is between 0 and 3.4 MPa (0 to 493

PSI) depending on the lever angle, the pilot valve is

normal.

3. check the spool operation

Disconnect the hose connecting the control valve (slew

block) and the slew motor from the control valve. Fit
the pressure gauge to the discharge port on the con

trol valve.

• Operate the lever (slew) and measure the pressure.
• If the measured value is as below, the spool is nor

mal.

Supply pressure: 20.0 MPa (2901 PSI)

4. check the slew pressure

Measure the pressure at the right and left slew relief

valves.

• If the measured value is within specifications, the

slew pressure is normal.

“2. Service data, Performance criteria”

if the pressure adjustment is possible, the adjustment

of the slew relief valve is faulty. if the pressure adjust-
ment is not possible, the slew relief valve is faulty.

5. check the slew motor

Separate the slew motor (1) from the turntable (2), and

then try turning the turntable (2).
• Does not turn.....The slew bearing (3) is faulty.
• Turns

..................

The slew motor (1) is faulty.

“4. Disassembly and assembly, Travel motor”

'$,=

Slewing

TroubleshooTing

5D0AX00

sleWing

Slew right or left is not possible

check the pilot valve

Faulty

repair or replace the pilot
valve

normal

check the spool opera-
tion

Faulty

Repair or replace the housing

block

normal

check the slew relief
valve

Faulty

repair or replace the slew re-
lief valve

normal

The slew motor is faulty

repair or replace the slew
motor

1. check the pilot valve

it is likely that only the pilot valve spool on the side

where slewing is not possible is faulty.

“No slewing is possible, 2. Check the pilot valve”

2. check the spool operation

it is likely that the spool does not move in the direction

in which slewing is not possible.

“No slewing is possible, 3. Check the spool op

eration”

3. check the slew relief valve

Switch between the left and right slew relief valves. If

slewing becomes possible, the relief valve is faulty.

4. The slew motor is faulty

“4. Disassembly and assembly, slew motor”

'$,=

Slewing

TroubleshooTing

5D0AX00

sleWing

Slewing is slow or lacks force

is the time needed for

slewing within specs?

Within specs

normal

slow

check the pilot valve

Faulty

repair or replace the pilot
valve

normal

check the spool opera-
tion

Faulty

Repair or replace the housing

block

normal

check the slew pressure

Pressure too low

Adjust the slew relief valve
pressure

Adjust to set pressure

normal

Pressure does not rise

repair or replace the relief
valve

check the slew motor

Faulty

repair or replace the slew
motor

normal

Slew bearing is faulty

replace

1. is the time needed for slewing within specifica-

tions?

“2. Service data, Performance criteria”

2. check the pilot valve

“No slewing is possible, 2. Check the pilot valve”

3. check the spool operation

“No slewing is possible, 3. Check the spool op

eration”

4. check the slew pressure

“No slewing is possible, 4. Check the slew pres

sure”

5. check the slew motor

“4. Disassembly and assembly, slew motor”

Slewing

TroubleshooTing

5D0AX00

sleWing

The machine slews, but overruns a lot when slewing stops, or slewing cannot be stopped

is the amount of overrun

when slewing stops with

in specs?

Within specs

normal

out-of-specs

check the pilot valve

Faulty

repair or replace the pilot
valve

normal

check the spool opera-
tion

Faulty

Repair or replace the housing

block

normal

check the slew pressure

Pressure too low

Adjust the slew relief valve
pressure

Adjust to set pressure

Pressure does not rise

repair or replace the relief
valve

1. is the amount of overrun when slewing stops within

specs?

“2. Service data, Performance criteria”

2. check the pilot valve

check if the spool of the pilot valve returns to the neu-

tral position when the operation lever (slew) is released
after operation. Disconnect the hose connecting the
pilot valve and control valve (slew block) from the con

trol valve. Fit the pressure gauge to the hose just dis

connected.

• Operate the lever (slew) and then release it to read

the pressure gauge.

• If the pressure is zero, the pilot valve is normal.

'$,=

Slewing

TroubleshooTing

5D0AX00

sleWing

3. check the spool operation

Check if the spool of the control valve (slew block) re

turns to the neutral position when the operation lever

(slew) is released after operation. Disconnect the hose
connecting the control valve (slew block) and the slew
motor from the control valve. Fit the pressure gauge to
the discharge port on the control valve.
• Operate the lever (slew) and then release it to read

the pressure gauge.

• If the pressure is zero, the spool is normal.

4. check the slew pressure

“No slewing is possible, 4. Check the slew pres

sure”

'$,=

Slewing

TroubleshooTing

5D0AX00

sleWing

When stopped on a slope, the upperstructure cannot maintain its posture

is the slew spontaneous
drop within specs?

Within specs

normal

out-of-specs

check the slew pressure

Pressure too low

Adjust the relief valve
pressure of the slew brake
valve

Adjust to set pressure

normal

Pressure does not rise

repair or replace the slew re-
lief valve

check the slew motor

Faulty

repair or replace the slew
motor

1. is the slew spontaneous drop within specs?

“2. Service data, Performance criteria”

2. check the slew pressure

“No slewing is possible, 4. Check the slew pres

sure”

3. check the slew motor

“4. Disassembly and assembly, slew motor”

TROUBLESHOOTING

BOOM

5G0AX001

BOOM

The boom cylinder does not move

1. Check the operation of actuators other than of the

boom cylinder.

Determine if only the boom cylinder is faulty by
checking the operation of actuators for the devices
listed in the table on the right. If one of them is faulty,
check the main relief valve and the hydraulic pump
(main).

“5. Troubleshooting, Overall machine, All sys-
tems working, but insufficient force”

Check the operation of
actuators other than of
the boom cylinder.

Normal

Check the pilot valve.

Faulty

Repair or replace the pilot
valve.

Normal

Check the spool opera-
tion.

Faulty

Repair or replace the housing
block.

Normal

Test by replacing the port
relief valve.

Problem solved

The port relief valve is
faulty.

Repair or replace the port re-
lief valve.

Normal

Check the boom cylinder.

Faulty

Repair or replace the boom
cylinder.

Lever to operate

Device to check

Relief valve

Pump

Right travel

Takeuchi Mini Excavator TB215R (No.215000003~). Operator's Manual - page 15