Service Manual

Chapter 9 - Cooling system

Cooling system.......................................................................................................................9.00
1 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.00.3
2 Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.00.5
2.1 Electric schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.00.5
2.2 Hydraulic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.00.7
3 Location of the components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.00.9
4 Functional description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.00.13
4.1 Hydraulic pumps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.00.13
4.2 Temperature regulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.00.17
5 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.00.23
5.1 Overheating in the hydraulic oil cooling circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.00.23
5.2 Overheating in the engine cooling circuit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.00.24
6 Adjustment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.00.27
7 Components description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.00.29
7.1 Hydraulic pump A11VO75DRX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.00.29
7.2 Hydraulic fixed displacement motor «FMF» . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.00.33
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 Service Manual Cooling system
Technical data

9.00: Cooling system

On the hydraulic excavator R 9250, the engine coolant is cooled in radiators, which are ventilated by
one cooling fan.
The cooling fan is driven hydraulically by the pump P6.1 that supplies one hydraulic motor MF1.
The hydraulic oil is cooled in radiators, which are ventilated by one cooling fan.
The cooling fan is driven hydraulically by the pump P6.2 that supplied one hydraulic motor MF2.

1 Technical data

R 9250 R 9250
Oil cooling Water cooling

Cooling pump Type Combi pump

A11VO75DRX+A11VO75DRX

Nominal RPM* min-1 2226 2226

Pump delivery max* cm³ 74 74
Pump flow max* l/min 280 280
Pump flow max hydraulically adjusted* l/min 183 183

Hydraulic motors Nb / Type 1 / FMF 90 1 / FMF 90

Nominal RPM* min-1 1200 1150

* This data are valid when engine runs at nominal speed.

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Technical data

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Schematic

2 Schematic

2.1 Electric schematic

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Schematic

A1019 Regulation plate

B2 Transmitter / engine coolant temperature
B3 Transmitter / coolant level
B14 Transmitter / hydraulic oil level
B67 Transmitter / hydraulic oil temperature
E1038 Connection box regulation
F148 15A Fuse / A1019
S74 Safety switch engine Flow
U16 Electronic box BST
X1-1 Connector 24 poles / U16 BST
X71 Connector 24 poles / A1019
X76 Connector 2 poles / A1019
X77 Connector 4 poles / A1019
X81 Connector 7 poles / A1019
X135 Connector 40 poles / U16 BST
X300 Kl31 electronic ground E1005
X811 Connector 2 poles / Y10_1
X812 Connector 2 poles / Y10_2
X846 Connector 31 poles / U18 Quantum
X858 Connector 24 poles / E1038
Y10_1 Solenoid valve / water ventilator
Y10_2 Solenoid valve / oil ventilator
Kl31 Ground
+24V Circuit 24 V

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Schematic

2.2 Hydraulic
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Schematic

CP2 Lower collecting pipe / support control valves

CP4 Collecting pipe before oil cooler
CP5 Collecting pipe after oil cooler
CP6 Collecting pipe for control valves
MF1 Oil fan motor
MF2 Water fan motor
P3 Working pump Nb. 3
P6.1 Water cooler fan pump
P6.2 Oil cooler fan pump
SP Suction pipe
SU1 Servo oil unit
Y10.1 Regulation solenoid valve: water fan
Y10.2 Regulation solenoid valve: hydraulic oil fan

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Location of the components

3 Location of the components

Cooling pumps P6.1 and P6.2

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Location of the components

Regulation solenoid valves Y10.1 and Y10.2

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Location of the components

Hydraulic motor FMF and cooling fan

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Regulation plate (A1019) Transmitter for hydraulic oil level (B14) and
temperature (B67)

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Location of the components

Regulation connection box (E1038) Hydraulic manual operation (E1004)

Electronic box BST (U16)

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Functional description

4 Functional description
The variable displacement pumps P6.1 and P6.2 supply oil to the constant volume hydraulic motors
FMF for cooler fan driven. The control pressure for the pumps displacement regulation is generated
by the regulation solenoid valves Y10.1 and Y10.2.
These valves control the pressure applied on the pressure cut off valve and so the pump angle. The
opening of the regulation solenoid valves Y10.1 depends on the engine coolant temperature and oth-
ers parameters (see next § temperature regulation). The opening of the regulation solenoid valves
Y10.2 depends on the hydraulic oil temperature (see next § temperature regulation).
Each hydraulic motor FMF is equipped with a suction valve to prevent cavitation and with a pressure
cut off valve to prevent mechanical damages if the corresponding fan is blocked.

4.1 Hydraulic pumps

4.1.1 Description
The pump A11VO75DRX is described in the § hydraulic pump A11VO75DRX

4.1.2 Regulation
The operation of the engine cooling pump and the hydraulic oil cooling pump are the same, and the
regulation pressure values are the same too.
The regulation solenoid valves Y10.1 and Y10.2 are installed between the port «Fa» (replenishing
pressure) and the regulators.
We use here the pump P6.2 to describe the functioning.

Pressure regulation
This regulation allows to adjust the pump flow in function of the pump high pressure Hd.
• The pump high pressure is applied on the regulator 24.2 via a disk.
• The spring is adjusted so that the pressure delivered by the pump drives the motors (and so the
fans) at the prescribed speed.
• While the nominal value of the pressure is not reached, the regulator 24.2 connects the bottom
side of the control piston 21.1 to the pump high pressure Hd via the regulator 24.2 through the
throttle 21.3. The pump is then swivelled out.
• As soon as the nominal pressure value in the circuit is reached, the pump high pressure Hd
pushes the regulator 24.2 to the right. The regulator 24.2 connects the bottom side of the control
piston 21.2 to the pump high pressure Hd via the regulator 24.2 through the throttle 21.4. The
pump is then swivelled in and the equilibrium is reached.

Flow regulation
This regulation allows to adjust the pump flow in function of the opening of the regulation solenoid
valves. The solenoid valves receive a regulating current from the BST depending on recorded pa-
rameters (the fuel temperature, the coolant temperature and the air intake manifold temperature for
Y10.1, the oil temperature for Y10.2). See next § temperature regulation.
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• Acting like a variable throttle, the regulation solenoid valve Y10.2 changes the pilot pressure (30
bar) into the positioning pressure (Pst).
• The positioning pressure (Pst) is applied on the regulator via a circle (this surface is bigger as
the crown surface on which the pump high pressure Hd is applied).
• Depending on its position (and so on the value of the positioning pressure), the regulator 24.2
makes the value of the regulation pressure (Preg) change. It connects the bottom side of the
control piston 21.1 or the control piston 21.2 either with the pump high pressure Hd or with or
with the tank pressure. The pump is then swivelled out or back until a new equilibrium is
reached.

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Functional description

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Functional description

Situation for cold temperature

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• When the machine is cold, the current on Y10.2 is maximal, Y10.2 is opened.
• The positioning pressure is maximal and thanks to the high pressure the regulator 24.2 is
pushed to the right.
• Then the bottom side of the piston 21.2 is connected to the high pressure via the regulator 24.2.
• As the rode side of the piston 21.2 is connected to the high pressure, the pump swivels to min-
imum angle.
• The fan speed is minimal.

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Functional description

Situation for intermediate temperature

• When the temperature of the machine increases, the current on Y10.2 decreases and Y10.2
gets partially closed.
• Y10.2 acts as a throttle on the pilot pressure. The pilot pressure applied on regulator 24.2 side
decreases.
• The spring partially pushes the regulator 24.2 to the left. The pressure applied on the bottom
side of the control piston 21.2 decreases. So the piston 21.1 moves to the right, and the piston
21.2 move to the left.
• The pump swivels out to a greater angle. The fans speed increases until a new balance with the
temperature is reached.
• The fan speed is intermediate.

Situation for hot temperature

• When the temperature of the machine reaches the upper limit, the current on Y10.2 has a min-
imum value. Y10.2 get completety closed.
• The positioning pressure becomes very low. The spring pushes the regulator 24.2 completely
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to the left.
• The pressure applied on the bottom side of the control piston 21.2 decreases. So the piston 21.1
moves completely to the right, and the piston 21.2 move to the left.
• The pump swivels out to maximum angle.
• The fan speed reached its maximum value.

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Functional description

4.2 Temperature regulation

4.2.1 Hydraulic oil

The hydraulic oil temperature sensor B67 and the hydraulic oil level sensor B14 are situated on top
of the hydraulic tank.
The resistance of the sensor B67 is changing in relation with the hydraulic oil temperature in the tank.
The first BST (U16) receives this resistance value and convert it in a temperature value in °C (see
graph R=f(T)).

The BST supplies the RSV Y10_2 with a regulating current, which depends directly of the hydraulic
oil temperature. The responses I (RSV for Y10_2)=f(T) are pre-programmed in the BST unit U16 (see
graph IY10.2 = f(T)).
This current is used to regulate the pump because the solenoid valve Y10.2 acts as a variable throttle
and controls the pressure applied on the pressure cut off valve. This allows to control the positioning
piston and then the pump angle. Consequently, the fan speed is directly controlled by the BST.
A green light diode on the regulation connection box E1038 lights up if there is current on Y10.2. This
diode is used to check rapidly if there is a problem in the electrical circuit.
At the start, the current supplying Y10.2 is blocked at 500 mA during one minute. The regulation
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works normally after one minute. This makes some oil flow in the cooling circuit at the start.
In case of safety operation (by pushing the switch S74), the relay on the plate A1019 is energised
and the current on RSV Y10_2 is open circuited. The RSV is closed thus the pump swivels out to
maximum angle. In this case, the fans turn at maximum speed.

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Functional description

4.2.2 Engine coolant

The QUANTUM system receives several parameters from censors located on the engine. Three pa-
rameters are used to regulate the fan speed:
• the fuel temperature
• the coolant temperature
• the air intake manifold temperature
The QUANTUM system calculates a pulse wide modulated signal (PWM) depending on the values
of the measured parameters.
If the temperature is below the low regulation limit (fan on with low speed), the PWM is equal to the
maximum (95%).
Between the two regulation limits (low and high), the signal decreases in relation with the most im-
portant proportion between the measured value and the low and high limits in all the three tempera-
ture ranges. It means that the QUANTUM system calculates the lower PWM of the measured
parameters.
Above the high limit value (fan on with full speed), the PWM signal is equal to 5%.
The lower PWM (which corresponds to the most unfavourable parameter of the three measured pa-
rameters) is then sent to the regulation plate A1019. This plate converts the PWM signal in an ana-
logical signal. The variation of the intensity of this signal is proportional to the PWM between 5% and
95%. This signal is then amplified by the BST and is sent via the plate A1019 to the regulation sole-
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noid valve Y10.1.

At the start, the current supplying Y10.1 is blocked at 500 mA during one minute. The regulation
works normally after one minute. This makes oil flow in the cooling circuit at the start.
In case of safety operation (by pushing the switch S74), the relay on the plate A1019 is energised
and the current on RSV Y10_1 is open circuited. The RSV is closed and thus the pump swivels out
to maximum angle. In this case, fans turn at maximum speed.

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Functional description

Schematic of the temperature regulation

Fuel tem- Coolant tem- Air intake mani- PWM 24V/ A1019 Y10_1
per pera- fold tem- 256
atu ture perature Hz
re

Low regulation value / 86 °C 54 °C 95 % 18 mA 880 mA

High regulation value 68 °C 94 °C 83 °C 5% 1 mA 250 mA

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Functional description

Relation between measured values and PWM

Pulse Wide Modulated 5%

Warning: the values of this graphic are indicative

Pulse Wide Modulated 95%

Warning: the values of this graphic are indicative
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Functional description

Relation between PWM and IA1019 and IY10.1

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Functional description

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Troubleshooting

5 Troubleshooting

5.1 Overheating in the hydraulic oil cooling circuit

The fan turn at the nominal speed

N Y • Check the cooling circuit (oil level, exchanger core dirty,

fan blades, ...).
• The air circulation is disturbed.

Disconnect the regulation solenoid valve

(RSV). Fan should now turn at
nominal speed.

N Y Reconnect the RSV and check the intensity at the RSV. The
relation between intensity and temperature is correct
(see curve I(RSV)=f(T)).

N Y

Replace the RSV

Check the transmitter resistance. The relation between tem-

perature and transmitter resistance is correct, see
curve R=f(T) for oil transmitter.

N Y

The transmitter is defec- Check the BST.

tive. Replace the Replace the BST if neces-
transmitter sary

Check the maximum oil pressure of the

pump and compare it with the
value given in the schedule
«Specifications» (see § 5). The
pressure is well adjusted.

Y N Adjust the pressure at the prescribed value (see § 5)

Close off Fa port on the pump. The fan

speed increases to the right value

N Y Regulating solenoid valve is defective or leaking. Replace

the RSV.
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Measure the oil flow in the circuit. The

relation between this oil flow and
the fan speed is correct (see
curve Q=f(N)).

N Y The hydraulic pump volumetric efficiency is poor. Change

the pump if necessary.

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Troubleshooting

The hydraulic motor volumetric effi-

ciency is poor if the point is below
and right of the wear limit line
(curve Q=f(N)). Change the motor
if necessary

5.2 Overheating in the engine cooling circuit

The fan turn at the nominal speed

N Y • Check the cooling circuit

• (coolant level, exchanger core dirty, fan blades, ...)
• The coolant flow in the exchanger is disturbed (for example, the ther-
mostat on the engine can be defectuous).
• The air circulation is disturbed.

Disconnect the regulation solenoid

valve (RSV). Fan should
now turn at nominal speed

Y Reconnect the RSV and check the intensity at the RSV. The intensity
value is approx. 250 mA.

N Y

Replace the RSV

Check the square signal from the Quantum with an oscilloscope or a volt-
meter in direct current. The value is approx. 5%×24 = 1,2V.

N Y

Check the intensity at A1019 output. The value

is approx. 1mA.

N Y

Check the BST and Check the plate

replace it if A1019 plate
necessary and replace it
if necessary

The trouble was cause by the Quantum or the censors. Replace the
Quantum or the sensors or get the engine monitoring system
repaired by a Cummins representative.
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Check the maximum oil pressure of

the pump and compare it
with the value given in the
schedule «Specifications»
(see § 5). The pressure is
well adjusted.

Y N Adjust the pressure at the prescribed value (see § 5).

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Troubleshooting

Close off Fa port on the pump. The

fan speed increases to the
right value.

N Y Regulating solenoid valve is defective or leaking. Replace the RSV.

Measure the oil flow in the circuit.

The relation between this oil
flow and the fan speed is
correct (see curve Q=f(N)).

N Y The hydraulic pump volumetric efficiency is poor. Change the pump if

necessary.

The hydraulic motor volumetric effi-

ciency is poor if the point is
below and right of the wear
limit line (curve Q=f(N)).
Change the motor if neces-
sary
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Troubleshooting

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Adjustment

6 Adjustment
 For adjustment instructions, refer to the section "Adjustment procedure R9250" in chapter 3
"Technical Data" of this manual.
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Adjustment

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Components description

7 Components description

7.1 Hydraulic pump A11VO75DRX

The variable displacement pump A11VO75DRX comprises two units arranged in tandem and is de-
signed as axial piston swash plate pumps. It is used to supply hydraulically auxiliary circuit (such as
the cooler fan motors on excavator R 9250).
Axial piston pumps are energy converters: they transform mechanical energy into hydraulic energy
by their axially directed pistons in a cylinder housing.
The pistons with glide shoes rotate on the swash plate. Because of the adjustable inclination of the
gliding surface, a corresponding piston stroke in the cylinder is created, and thus the adjustable flow
of the hydraulic pump.

7.1.1 Construction of variable displacement pump A11VO

The variable displacement pump A11VO comprises two units arranged in tandem and designed as
axial piston swash plate pumps.
The pump is consisting of six main parts:
– The central housing 3.0 with suction and pressure ports also contains the control pistons 20.1 and
21.1 for the both pump units.
– The both complete pump gears 20 and 21.
– The both pump regulators 23 and 24, which are mounted to the connector housing 3.0.
– The closing flange 11.
The pumps gears (shaft, cylinder and pistons) are driven by the Diesel engine via the coupling.
The variable displacement pumps are supplied with hydraulic oil via the suction ports «S» in the cen-
tral housing 3.0. It delivers hydraulic oil into the working circuits via connection «A».
The leak oil from the pumps flows via the leak oil connection «T» to the tank.
The regulators 23 / 24 control the swivel angle, and thus the oil delivery of the pump units via the
positioning piston 20.1 / 20.2 / 21.1 / 21.2. The position of these pistons depends on the pump high
pressure, and also on external control pressures, which are connected to the regulator. These exter-
nal control pressures are different according to the regulation type.
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Components description

3.0 Central housing

11 Closing flange
20 First pump
21 Second pump
23 First pump regulator
24 Second pump regu-
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7.1.2 Function of hydraulic pump

Function of the pump power gear

The input shaft 1.10, with bearing mounting in the pump gear 11, drives the cylinder 1.11. Nine pis-
tons 1.9 are mounted parallel around the driving shaft in the cylinder.The piston bottoms are ball
shaped and set in the slide shoes 1.16. They are held by return plate 1.14 and return ball 1.13 on the
swivelling, but not rotating swivel crossbar 1.2 with thrust washer 1.15.

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Components description

The slide shoes 1.16, mounted hydrostatically on the thrust washer 1.15 (via bore holes in the pistons
and slide shoes) reduce the large sliding surface between the slide shoes and the thrust washer to a
minimum.
When not under pressure, the cylinder 1.11 is pressed against the control lens 1.12 by the springs
1.17, installed in the return ball 1.13. As pressure increases, cylinder and control lens are so well bal-
anced by hydraulic forces, that even at high loads an oil film is maintained on the surfaces of the con-
trol lens, while at the same time leak oil is kept to a minimum. Part of the leak oil is used to lubricate
all moving parts and then flows externally to the tank.
If the cylinder 1.11 turns, the pistons 1.9 move in a double stroke from the lower to the upper limit and
then reverse. The stroke is carried out in relations to the swivel angle of the swivel crossbar 1.2 and
is responsible for the flow volume.
The axial piston unit moves the oil via kidney shaped control inlets in the control lens 1.12. Four of
the moving pistons draw oil through the kidney shaped oil inlets on the suction side of the pump. The
other four pistons displace the oil which is supplied via the kidney shaped oil outlets to the pressure
side of the pump, moving oil via connection A into the hydraulic system. A ninth piston is moving ei-
ther at the upper or the lower limit, at dead center, i.e. just changing directions.

Pump displacement
The control pistons 20.1 and 20.2, connected with the swivel crossbar 1.2, displace the pump from
maximum to minimum swivel angle. The regulator 23 controls the displacement of the control piston
20.1 and 20.2 while connecting their large surface either with high pressure of the pump, or with tank
pressure.
According to the regulation type, the control procedure of the pump swivel angle by the control piston
is different. For exact description, refer to part «cooling system».
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Components description

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Components description

1 Pump gear complete 11 Closing flange

1.1 Pump housing 11.1 O-ring
1.2 Crossbar 11.2 O-ring
1.9 Piston with glide shoe
1.10 Driving shaft 20.1 Control piston
1.11 Cylinder 20.10 Control piston (first part)
1.12 Control lens 20.11 Pin (second part)
1.13 Return ball 20.12 Spring
1.14 Return plate
1.15 Slide plate 20.2 Control piston
1.16 Slide shoe 20.20 Control piston (first part)
1.17 Spring 20.21 Pin (second part)
1.19 Plug 20.22 Spring
1.23 O-ring
1.24 Adjustable stop 23 Regulator
1.25 Hex. head nut 23.1 Regulator solenoid valve
1.26 Adjustable stop 23.2 Plug
1.27 Hex. head nut

7.2 Hydraulic fixed displacement motor «FMF»

Oil motor - type FMF 90

Max. oil volume 90 cm³

Max. permissible leak oil quantity
at 320 bar /
at 150 bar /

Torques values:
Allen head screw 14 185 Nm
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Components description

7.2.1 Description
The FMF fixed displacement motor is used to drive cooling fans. The axial piston motor is designed
as a swash plate type motor.
Axial piston motors are energy converters: they transform hydraulic energy into mechanical energy
by their axially directed pistons in a cylinder housing.
The pistons with glide shoes rotate on the swash plate. Because of the inclination of the gliding sur-
face, a piston stroke is created in the cylinder, and thus the constant flow volume of the oil motor.

7.2.2 Function of oil motor, see diagram

Housing 12 contains nine pistons, which are located parallel in relation to the output shaft 3. The pis-
tons are contained in cylinder 4, which is connected by gears to the output shaft 3. The end of each
piston 5 is designed as a ball joint, which is mounted in glide shoe 5.1. They are held against the fixed
swash plate 6 by the retainer plate 7 and the return ball 8.
The hydrostatic support (oil film) between the glide shoes 5.1 and the fixed swash plate 6 (due to drill-
ings in piston 5 and glide shoes 5.1) reduces surface pressure between the glide shoe and the swash
plate.
In a no load or pressureless condition, the cylinder 4 is pressed against the control lens 9 by spring
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8.1, which is installed in return ball 8. As the system pressure increases, cylinder 4 and control lens
9 are so well balanced by hydraulic forces that even at high loads an oil film is maintained on the sur-
faces of the control lens as well as on the glide shoes. At the same time, leak oil is kept to a minimum.
Part of the leak oil is used for lubrication of all moving parts and then returned to the tank via an ex-
ternal line.
If pressurized oil enters at connection A or B, four pistons 5 are pressurized via kidney shaped inlets
in the control lens 9. On the opposite side, four more pistons 5 push the low pressure return oil
through kidney shaped inlets in control lens 9 and connection A or B to the tank. A ninth piston is at
dead center, which means at the point or reversing direction.

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Once the oil pressure reaches the four pistons on the pressure side, a certain force is created by oil
pressure and piston surface. This force is transferred via piston 5 and glide shoe 5.1 onto the swash
plate 6.
This radial force, which uses cylinder 4 as a lever, creates the torque, which is transferred via cylinder
4 to the output shaft 3. The amount of torque is in direct proportion to the system pressure, which
means high pressure = high torque. By applying oil to the opposite port (connection A or B), the
torque and direction of the hydraulic motor is reversed (right or left turn).
During a complete revolution of cylinder 4, pistons 5 perform a dual stroke from the lower dead center
to the top dead center and reverse. This stroke depends on the inclination of the swash plate 6 and
influences the oil quantity.
The displacement of the hydraulic motor remains the same until the oil supply from the variable flow
pump changes.

7.2.3 Maintenance and repairs

Liebherr hydraulic motors are maintenance free.
For resealing and repair work see the «Repair instructions for Liebherr fixed displacement oil motors
FMF».
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Components description

2 Roller bearing 14 Allen head screw

3 Drive shaft 15 Cover ring
4 Cylinder 16 Shaft seal
5 Piston 17 O-ring
5.1 Glide shoe 18 O-ring
6 Swash plate 19 O-ring
7 Retainer plate 22 Snap ring
8 Return ball 23 Snap ring
8.1 Spring 24 Pin
9 Control lens 26 Needle bearing
10 Dowel pin 27 Spacer
12 Housing 28 Spacer
13 Connector plate

LEC / en / Version: 05 / 2014

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