Eaton 70160 User manual

2
Model 70160
Table of Contents
Introduction.........................................................................................................2
Identification........................................................................................................3
Tools Required ....................................................................................................3
Parts Drawing......................................................................................................4 - 5
Parts List .............................................................................................................6 - 7
Repair information
Disassembly..................................................................................................8 - 10
Reassembly...................................................................................................11 - 12
Fault - Logic Troubleshooting..............................................................................13 - 17
Start-up Procedure ..............................................................................................18
Introduction
This manual provides service information for Eaton Models 70160 variable displacement piston pumps. Step
by step instructions for the complete disassembly, inspection, and reassembly of the pump are given. The
following recommendations should be followed to insure successful repairs.
Remove the pump from the application.
Cleanliness is extremely important.
Clean the port areas thoroughly before disconnecting the hydraulic lines.
Plug the pump ports and cover the open hydraulic lines immediately after they're disconnected.
Drain the oil and clean the exterior of the pump before making repairs.
Wash all metal parts in clean solvent.
Use compressed air to dry the parts. Do not wipe them dry with paper towels or cloth.
Compressed air should be filtered and moisture free.
Always use new seals when reassembling hydraulic pumps.
Lubricate the new rubber seals with a petroleum jelly (Vaseline®) before installation.
Torque all bolts over gasketed joints, then repeat the torquing sequence to makeup for gasket
compression.
Verifying the accuracy of pump repairs on an authorized test stand is essential.
Introduction

3
Model 70160
Single Pump - Product Number:
7 0 1 6 0 - R A A - 02
Tandem Pumps - Product Number:
7 8 1 6 3 - R A B - 02
Serial Number Code:
A 99 01 31 JB Tester's Initials
Day of Month (two digits)
Month (two digits)
Revision level of parts list.
Last two digits of year built.
( 98 for 1998 etc.)
Identification Numbers - Manually Variable Displacement Piston Pump
Stamped on each unit's mounting flange.
A - Product Number Description
70160 = Single Piston Pump
78162 = Single Piston Pump with Gear Pump
78161 = Tandem Piston Pumps
78163 = Tandem Piston Pumps with Gear Pump
B - Sequential Numbering
C - Engineering Design Code
A
A
B
B
Tools Required
1/2, 9/16, 7/8 & 1-1/8 in. sockets and/or end
wrenches
Torque wrench (136 N.m [100 lbf.ft] capacity)
Ratchet wrench
5/16 in. and 7/16 Allen wrenches or bit sockets
Internal and external retaining ring pliers
Small screwdrivers (2)
Hammer (soft face)
Light Petroleum Jelly
Seal driver or similar tool
Each order must include the following information.
1. Product and/or Part Number
2. Serial Number Code
3. Part Name
4. Quantity
C
C

4
Model 70160
Parts
Drawing
Pump drawn below is typical of a righthand rotation pump.
30
3-1
Press Fit
6
5
4
1
Shaft assembly for
rear pump of tandem.
Shaft assembly for
single pump
or front pump
of tandem.
1
7
7
8
8
8
8
910
10
910
10
11
11
29
48
12
24
41
16
Press Fit
23
17
17 14
3
50
50-1
51
22 Press Fit
22 Press Fit
51-1
13
14
40
39
41
Port
(D2)
Port
(D1)
39
Press Fit into
Cover plate

5
Model 70160
Parts
Drawing
2
2-1 2-2
26
26
21
20
18
1919-1
19
19-1
18
27
27
28
28
37
37
(K4-4)
2-1 2-2
26
26
21
20
18
19
19-1
19
19-1
18
2
27A
27B
28A
55-1
49 55-2
55-3
55-4
49-1 55
55-5
37
35
36
55-1
55
55-2
55-3
55-4
55-5
49
49-1
34
34-1
32
(K2-1)
K2-2
K2-3
32
(K3-1)
31
(K3-2)
33
(K3-3)
K3
K2
32
(K4-1)
K4-2
K4-3
K4
K1-1
32
(K2-2)
K2-3
K2-4
K1
46
46

6
Model 70160
Item Qty. Description
1 1 Drive Shaft
2 1 Endcover Assembly
3 1 Housing Assembly
4 1 Rotating Kit Assembly
5 1 Swashplate
6 1 Washer
+ 7 1 Retaining Ring
+ 8 2 Retaining Ring
9 1 Thrust Bearing
10 2 Bearing Race
+ 11 1 Shaft Seal, Drive
11 1 Viton Shaft Seal, Drive
11 1 Spacer
+ 12 1 Housing Gasket
13 1 Swashplate Insert
14 6 Washer
+ 16 1 Shaft Seal, Trunnion
17 6 Screw, Cap
18 2 Spring
19 2 Plug Assembly
+ 19-1 2 O-ring, 2.38 mm Dia. x 22.23 mm ID. [.0937 in. Dia. x .875 in. ID.]
20 1 Relief Valve for Port "C"
21 1 Relief Valve for Port "D"
22 2 Cone Bearing
23 1 Coverplate Sub Assembly
24 1 Coverplate Sub Assembly
26 2 Dowel Pin
27 2 Cap Screws, 5/16-18, 50.8 mm [2 in.] Long
27A 2 Cap Screws, 5/16-18, 82.6 mm [3.25 in.] Long
27B 2 Cap Screws, 5/16-18, 88.9 mm [3.5 in.] Long
28 2 Cap Screws, 5/16-18, 63.5 mm [2.5 in.] Long
28A 2 Cap Screws, 5/16-18, 95.3 mm [3.75 in.] Long
28B 2 Cap Screws, 5/16-18, 101.6 mm [4.00 in.] Long
29 1 Key, Drive Shaft
30 1 Key, Tapered Arm
31 1 Cover Plate (In K3 kit)
+ 32 1 O-ring (In K1, K2, K3, & K4 kit)
33 2 Cap Screws, Cover Plate (In K3 kit)
34 1 Plug Assembly
+ 34-1 1 O-ring, 2.21 mm Dia. x 16.36 mm ID. [.087 in. Dia. x .644 in. ID.]
+ 35 1 Molded O-ring
36 1 Charge Pump Adaptor
37 1 Gerotor set and coupler sub-assembly
37 1 9 tooth coupler (In Kit 4)
37 1 11 tooth coupler (In Kit 5)
39 2 Cup, Bearing
40 1 Ring, Crush
41 2 O-ring, 2.38 mm Dia. x 66.68 mm I.D. [.0937 in. Dia. x 2.625 in. I.D.]
42 4 Washer
46 1 Mounting Bracket, Square shaped
46 1 Mounting Bracket, "V" shaped
Parts List

7
Model 70160
Parts List
48 1 Valve Plate
Righthand (CW) Rotation
Lefthand (CCW) Rotation
49 1 Plug Assembly
49-1 1 Plug Assembly
+ 50-1 1 O-ring, 1.98 mm Dia. x 11.89 mm ID. [.078 in. Dia. x .468 in. ID.]
51 1 Plug Assembly
+ 51-1 1 O-ring, 1.98 mm Dia. x 11.89 mm ID. [.078 in. Dia. x .468 in. ID.]
55 1 Bypass Valve sub-assembly
+ 55-1 1 Retaining Ring
55-2 1 Separator Plug
55-3 1 Separator
+ 55-4 1 O-ring, 1.59 mm Dia. x 9.53 mm I.D. [.0625 in. Dia. x .375 in. I.D.]
+ 55-5 1 O-ring, 2.46 mm Dia. x 19.18 mm I.D. [.097 in. Dia. x .755 in. I.D.]
Mounting Kits
K1 1 Tandem Piston Pump Mounting Kit
K1-1 1 35T Coupler, 36.8 mm [1.45 in.] long
K1-2 1 O-ring, 1.59 mm Dia. x 101.6 mm ID. [.0625 in. Dia. x 4 in. ID.]
K1-3 2 Cap Screws
K1-4 2 Washer
K2 1 Gear Pump Mounting Kit
K2-1 1 O-ring, 1.59 mm Dia. x 82.55 mm ID. [.0625 in. Dia. x 3.25 in. ID.]
K2-2 2 Washer
K2-3 2 Cap Screws
K3 1 Cover Plate Kit
K3-1 1 O-ring, 1.59 mm Dia. x 82.55 mm ID. [.0625 in. Dia. x 3.25 in. ID.]
K3-2 1 Cover Plate
K3-3 2 Cap Screws
K4 1 Gear Pump Mounting Kit with Coupler
K4-1 1 O-ring, 1.59 mm Dia. x 101.6 mm ID. [.0625 in. Dia. x 4 in. ID.]
K4-2 2 Washer
K4-3 2 Cap Screws
K4-4 1 9T Coupler
Seal Repair Kit
• 1 Seal Repair Kit (see Parts Manual for part numbers)
Legend + Included in seal repair kit.
Item Qty. Description

8
Model 70160
Disassembly
The following disassembly procedure applies to a single pump
with or without gear pump The
repair procedure for tandem
pumps, once they are separated, is
basically the same. The basic
configuration differences between
a single and tandem pumps are the
endcovers, pump shafts and
housing assemblies. In most
cases, only the rear pump of
tandem units contain a charge pump, which is common to
both the front and rear pump. The rear tandem pump does not
incorporate a shaft seal.
Thoroughly clean the Eaton Model 70160 or 78162 variable
displacement pump before any
repairs are attempted. When
working on tandem pumps,
separate the front and rear pumps
first.
1Support the pump with the
input shaft down. Use a 1/2 in.
socket or end wrench to remove
the pump adapter cover plate or
gear pump (see Figure 2).
2Use a pick or similar tool to
remove the adapter cover plate or
gear pump o-ring. (See Figure 3)
3Use a 7/16 in. Allen wrench or
bit socket remover to remove the
charge pressure relief valve spring
retainer from the pump adaptor
assembly (see Figure 4).
4Use a pencil magnet or similar
tool to carefully remove the charge
pressure spring and poppet from
the pump adaptor assembly. (See
Figure 5) Use caution not to drop
the charge pump poppet into the
pump adaptor assembly.
5The charge pressure relief
valve and poppet may be of the
standard or high pressure type. The
(6.9 to 10.3 bar [100 to 150 PSI])
standard spring and poppet are
shown on the bottom and the
optional high pressure (13.7 to
20.7 bar [200 to 300 PSI]) spring
and poppet is shown on the top.
The same charge pressure relief valve spring retainer is used
with either the standard or high
pressure (see Figure 6).
6Use a 7/8 in. socket or end
wrench to remove the optional
bypass valve assembly from the
endcover (see Figure 7).
7The internal seal may be
replaced by first removing the
small retaining ring on the end of
the bypass valve. Remove and
replace the o-rings (see Figure 8).
8Use a 1-1/8 in. socket or end
wrench to remove the two high
pressure relief valves from the
pumps endcover assembly (see
Figure 9). Remove plug, spring, and
relief valve as shown from each
side (see Figure 10). Each system
relief valve assembly is identified by
both its part number and relief valve setting as shown in Parts
Information manual.
9Firmly support the pump assembly. Use a 1/2 in. socket or
end wrench to remove the four cap screws retaining the charge
pump adapter assembly.
10 With the cap screws removed,
remove the charge pump adaptor
assembly from the endcover (see
Figure 11).
Note: The front pump assemblies
do not have charge pump adapter
assemblies.
11 Turn the adapter assembly
over. Use an o-ring pick or similar
tool remove the o-ring seal (see
Figure 12).
12 Inspect the gerotor pocket and
needle bearing located in the
charge pump adapter. The needles in the needle bearing must
remain intact in the bearing cage.
Repair Information- Disassembly
Figure 1
Figure 2
Figure 3
Figure 5
Figure 4
Figure 6
Figure 7
Figure 8
Figure 9
Figure 10
Figure 11
Figure 12

9
Model 70160
13 When the needle bearing
assembly is replaced, the
numbered end of the bearing must
face toward the flange side of the
adapter to the dimension as shown
(see Figure 13).
14 With the charge pump adapter
removed, remove the charge pump
outerring and inner gerotor ring
assembly (see Figure 14 and 15).
15 Charge pumps are available in
two different displacements Charge
pump displacements are based on
the thickness of the gerotor
assembly and the depth of the
pocket located in the charge pump adapter. To determine the
displacement, refer to the table below.
Gerotor Pocket Depth
Displacement Depth of Pocket
cm3/r [in3/r] mm [in.]
6.9 [.42] 6.35 [.25]
13.8 [.84] 12.7 [.50]
16 To separate the endcover
assembly from the dowel pins in
the pump housing assembly, insert
two screwdrivers between
endcover and housing assembly
and pry upward (see Figure 16).
17 After separation, remove the
endcover from the housing
assembly.
18 Turn the endcover assembly
over and inspect the needle
bearing. The needles in the needle
bearing must remain intact in the
bearing cage (see Figure 17).
19 When the needle bearing
assembly is replaced, the
numbered end of the bearing must
face the valve plate side of the
endcover to the dimension as
shown (see Figure 18).
20 With the endcover removed,
remove the gasket from the pump
housing assembly and discard (see
Figure 19).
21 Remove the valve plate from the piston block assembly.
Note: This valve plate may have stuck to the endcover
assembly that was previously removed.
22 Valveplate directional rotation (CW or CCW) is identified
by the location of the metering slots located on the face of the
valve plates. Pump input
rotation should always turn
into the metering slots (see
Figure 20). A clockwise
valve plate is shown on the
left and a counter clockwise
valveplate is on the right.
Note: Whenever pump
input rotation is changed, the valve plate must be replaced
along with the desired rotation charge pump adapter.
23 Remove the rotating kit assembly
by carefully retaining it in the housing
assembly (see Figure 21). Lift the
housing and rotating kit assembly and
turn over assemblies allowing the
rotating kit assembly to slide down the
input shaft and out of the pump
housing.
24 With the rotating kit
assembly removed, remove the
piston assemblies, spider and
spider pivot from the piston
barrel.(see Figure 22).
25 Inspect the piston
assemblies, spider, spider pivot
and piston block. The piston block assembly usually requires
no further disassembly unless the pins or block spring are
damaged.
26 When any excessive wear or
scratches are noted on the face of
the piston block, the block
assembly must be replaced (see
Figure 23).
DO NOT LAP THE FACE OF PISTON
BLOCK ASSEMBLY.
27 To remove the input shaft
assembly, use a pair of internal
snap ring pliers and remove the
shaft seal retaining ring from the
housing assembly (see Figure 24).
Numbered End
Gerotor Pocket
2.41 mm
[.095 in.]
Flange
Figure 13
Figure 17
2.79 mm
[.110 in.]
1.91 mm
[.075 in.]
Numbered End
Figure 18
Figure 20
Figure 22
Figure 23
Figure 24
Figure 15
Figure 16
Figure 14
Figure 19
Figure 21
Repair Information- Disassembly

10
Model 70160
28 With the retaining ring
removed, use a small press to
press the shaft seal and input shaft
assembly from the housing
assembly.
29 With the input shaft assembly
removed, disassemble the
assembly for inspection by
removing the shaft seal, washer,
retaining ring thrust washers and
bearing (see Figure 26).
Note: The rear pump on tandem
units uses a spacer in place of
shaft seals.
30 To remove the swashplate
from the housing assembly, use a
9/16 in. socket or end wrench and
remove the three cap screws
retaining the control arm cover plate assembly. Start at the
cover plate with control arm. (see Figure 27).
31 With the retaining cap screws removed, insert two small
screwdrivers in the notches located
in the cover plate assembly and pry
upward. Make sure bearing cup
comes off with the cover plate (see
Figure 28).
Note: The crush ring in the control
arm trunnion cover does not need
to be removed (see Figure 29). The
only time the crush ring needs to
be removed is when either the
trunnion cover, the swashplate
assembly or the housing assembly
is replaced. A shim kit is then
required in the crush rings place.
32 Reposition the pump assembly
to remove opposite cover plate.
The bearing cup in this cover plate
is press fit and not removable.
Repeat steps 30 through 31.
33 To remove swashplate, first
use a small press and press the
drive shaft needle bearing out of
the housing.
34 With housing in the upright position rotate the swashplate
upside down, slide the swashplate toward the control side and
lift it from the pump housing (see Figure 30).
Note: The swashplate control shaft will fit out either side of the
pump housing. Be sure to note on which side of the housing
the control shaft protrudes before removing swashplate from
housing for correct reassembly orientation.
35 Use an o-ring pick or similar tool to remove the o-ring
seals from the two counter-bores
in the housing or the cover plates
(see Figure 31).
36 To remove the control side
cover plate lip seal, use a small
press and press the lip seal inward
(see Figure 32).
37 Remove the thrust plate from
the swashplate. The thrust plate is
reversible and either side may face
the swashplate (see Figure 33).
38 When the needle bearing is
replaced, the numbered end of the
needle bearing must face away
from the housing and pressed to
the dimension as shown (see
Figure 35).
Figure 26
Figure 27
Repair Information- Disassembly
Figure 32
Figure 34
1.78 mm
[.07 in.]
Numbered End Flange End of Housing
Figure 35
Figure 25
Figure 28
Figure 29
Figure 30
Figure 33
Figure 31

11
Model 70160
Reassembly
1Before reassembling the pump, replace all worn and
damaged parts, assemblies, seals and o-rings. Lubricate the
seals and o-rings with petroleum jelly to help retain them
during reassembly and to provide lubrication to the input and
control shaft seals. Lubricate all finished part surfaces freely
with clean hydraulic fluid to help provide start up lubrication
between all rotating parts.
2To reassemble the swashplate
assembly into the pump housing,
tilt the swashplate slightly and
install the control side of the
swashplate through the previously
noted or marked side of the
housing assembly (see Figure 36).
3With the swashplate installed,
lubricate the tapered bearing on the
non-control arm side of the
swashplate (see Figure 37).
4Lubricate and install the o-ring
seal into counter-bore of housing
(see Figure 37).
5Install the trunnion cover over
bearing and onto pump housing.
Install the three cap screws and
torque to 39,3 Nm [29 ft. lbs.] (see
Figure 38).
6Lubricate and install the
control arm shaft seal into the
control arm cover plate. Install with the lip of the seal facing
upward or to the inside of the pump (see Figure 39).
7If the housing, trunnion covers or swashplate assembly
have not been replaced, the existing crush ring may be re-
used. If you have replaced anyone of the above a shim kit must
replace the crush ring. See Parts Information manual for
number.
8Place the bearing cup into trunnion cover over the crush
ring or shims (see Figure 40).
9Lubricate and install the o-ring
seal into counter-bore of housing
(see Figure 41).
10 Install the trunnion cover over
the control shaft and into the pump
housing. Install the three retaining
cap screws and torque to 39,3 Nm
[29 ft. lbs.] (see Figure 42).
11 Using your fingers, tilt the
swashplate back and forth to check
the trunnion bearing preload.
Proper preload is achieved when
the swashplate has a very slight
tilting resistance. The swashplate
must not have any or very little side
clearance.
12 Reassemble the input shaft
assembly by installing the thrust
washer, thrust bearing, second
thrust washer, retaining ring,
washer and shaft seal (see Figure
43).
Note: The lip of the shaft seal must
point toward the center of the input
shaft.
13 Install the input shaft
assembly into the housing
assembly. Push the shaft seal in
just far enough so you can start the
shaft seal retaining ring.
14 Use a pair of snap ring pliers
to install retaining snap ring into
the housing assembly (see Figure
44).
15 Use a seal driver or similar
tool to press or drive the snap ring
and seal into the housing assembly
(see Figure 45).
CAUTION! Press or drive inward
until the snap ring snaps into the
snap ring groove located in the
pump housing assembly.
16 The thrust plate is reversible.
Either side will fit into the
Figure 38
Figure 42
Figure 43
Figure 44
Figure 45
Repair Information- Reassembly
Figure 36
Figure 37
Figure 39 Figure 40
Figure 41
Figure 46

12
Model 70160
swashplate. In most cases if any
irregularities are noted it is best to
replace the thrust plate (see Figure
46).
18 Lubricate and install the
thrustplate over the input shaft
assembly and into the swashplate.
The thrustplate must rest firmly in
its pocket located in the swashplate.
19 Reassemble the rotating kit
assembly by first aligning the
splines in the pivot with the splines
in the block. Install the pivot on the
block assembly pins (see Figure
47).
20 Use a small socket or similar
tool to help retain the pivot in the
centered position. Lubricate and
install the spider and piston
assemblies onto the pivot and
pistons into the piston block
assembly (see Figure 48).
21 Hold the housing assembly in
the vertical position then carefully
install the rotating kit by first
aligning with the splines on the
input shaft. With splines aligned,
install the rotating kit into the
pump housing (see Figure 50). Use
caution to ensure all parts are kept
in their proper position.
22 With the rotating kit installed,
reposition the housing assembly in
the input shaft down position and
install a new housing gasket (see
Figure 50).
23 Lightly coat the endcover side
of the valve plate with petroleum
jelly for retention during assembly.
Install the valve plate over the
needle bearing, aligning the small
slot on the outside of the valve
plate with the dowel pin in the
endcover (see Figure 51).
24 Carefully install the endcover
assembly by aligning it with the
dowel pins located in the pump
housing. Use caution not to
dislodge the valve plate (see Figure
54).
25 Align the spline of the gerotor’s inner ring, then lubricate
and install the inner ring and outer
ring over the input shaft and onto
the endcover assembly (see Figure
53).
Note: Before installing the charge
pump adaptor plate, offset the outer
ring of the geroter as shown.
26 With the gerotor assembly
installed, install new o-ring into
charge pump adapter plate and
place adapter onto endcover over
gerotor. Retain with cap screws.
Torque cap screws to 25 N•m [18.5
lbf•ft] (see Figure 54).
27 Install the two high pressure
relief valves. Torque valves 128,8 to
142,4 N•m [95 to105 lbf•ft] (see
Figure 55).
29 Lubricate and reassemble the
bypass valve assembly. Install the
bypass valve into the endcover.
Torque valve to 30,5±2 N•m
[22.5±1.5 lbf•ft] (see Figure 56).
30 Coat the charge pressure
poppet with petroleum jelly and
place poppet onto spring and install
into the adapter plate (see Figure
57).
31 Install the hollow charge
pressure relief valve retainer into
the adapter plate. Torque retainer to 6,8 to 9,5 Nm [5 to 7
lbf•ft].
32 Lubricate and install the o-ring on the cover plate or gear
pump. Install the cover plate or gear pump and two cap
screws. Torque cap screws to 36,6 to 40 Nm [27 to 31 lbf•ft].
The Model 70160 or 78162 variable displacement pump is now
ready for test and reinstallation.
Figure 48
Figure 49
Figure 51
Figure 54
Figure 55
Figure 56
Figure 57
Repair Information- Reassembly
Figure 47
Figure 50
Figure 52
Figure 53

13
Model 70160
1
Inspect
?
Repair
or
Replace
Defective
Action
Step
Comment
Number
Decision
Solution
Symptom:
Gauges Recommended
Inlet vacuum gauge: 2 bar to 1 bar [30 PSI to 30 inHg]
System pressure gauge: 700 bar [10,000 PSI]
Charge pressure gauge: 0 to 50 bar [0 to 600 PSI]
Case pressure gauge: 0 to 25 bar [0 to 300 PSI]
Explanatory
Diagram
This fault - logic troubleshooting guide is a
diagnostic aid in locating transmission problems.
Match the transmission symptoms with the problem
statements and follow the action steps shown in the
box diagrams. This will provide help in correcting
minor problems eliminating unnecessary machine
down time.
Following the fault - logic diagrams are diagram
action comments of the action steps shown in the
diagrams. Where applicable, the comment number of
the statement appears in the action block of the
diagrams.
Recommended Gauge Locations
Figure 58
Pressure Ports
Tee In Line to Check
System Pressure
Charge Pump Suction Port
Tee In Line to Check Inlet
Vacuum
Drain Port
Tee In Line to Check
Case Pressure
Auxiliary Port
Check Charge Pressure
Fault - Logic Troubleshooting
Bypass Valve
Location

14
Model 70160
Fault - Logic Troubleshooting
Inspect
Servo Control
(If used)
OK
12
Inspect
External Control
Linkage
Defective
Repair
or
Replace
Defective
Repair
or
Replace
Symptom: Neutral Difficult or Impossible to Find
Inspect
Heat
Exchanger OKOK OK
456
Check
Oil Level in
Reservoir
Fill to
Proper
Level
DefectiveBelow Level
Repair
or
Replace
Check
System
Pressure
Reduce
System
Load
High
OK 9
Inspect
Charge Relief
Valve
OK 11
Inspect
Charge
Pump 13
Inspect
Motor 12
Inspect
Inlet Screen
or Filter
Replace
Clogged
OK 8
Check
Charge
Pressure
10
Low OK
OK
Replace
Pump &
Motor
Inspect Pump
Bypass Valve
(If used)
OK 7
Inspect Heat
Exchanger
Bypass Valve
(If used)
OK
Defective
Repair
or
Replace
Defective
Repair
or
Replace
Defective
Repair
or
Replace
Defective
Repair
or
Replace
Defective
Repair
or
Replace
Symptom: System Operating Hot

15
Model 70160
Inspect
Servo Control
(If used)
OK OK
123
Inspect
External Control
Linkage
Defective
Repair
or
Replace
Inspect
System Relief
Valves
Defective
Repair
or
Replace
Defective
Repair
or
Replace
Symptom: Operates in One Direction Only
Inspect
Servo Control
(If used) OKOK OK
27
Defective
Repair
or
Replace
Inspect
Motor
12
Replace
Clogged
Check
Charge
Pressure
10
Low OK
Inspect Pump
Bypass Valve
(If used)
Replace
Pump &
Motor
Defective
Repair
or
Replace
Inspect
Inlet Screen
or Filter OK
OK OK
813
Defective
Repair
or
Replace
Inspect
Charge Relief
Valve
11
Inspect
Charge
Pump
Defective
Repair
or
Replace
Defective
Repair
or
Replace
Symptom: System Response Sluggish
Fault - Logic Troubleshooting

16
Model 70160
Check External
Control
Linkage OKOK OK
417
Check
Oil Level in
Reservoir
Fill to
Proper
Level
DefectiveBelow Level
Repair
or
Replace
Check
System
Pressure
OK 9
Inspect
Charge Relief
Valve
OK 11
Inspect
Charge
Pump 13
Inspect
Motor 12
Inspect
Inlet Screen
or Filter
Replace
Clogged
OK 8
Check
Charge
Pressure
10
Low OK
OK
Replace
Pump &
Motor
Inspect
Servo Control
(If used)
OK 2
Inspect Pump
Bypass Valve
(If used)
OK
Defective
Repair
or
Replace
Defective
Repair
or
Replace
Defective
Repair
or
Replace
Defective
Repair
or
Replace
Defective
Repair
or
Replace
High
Reduce
System
Load
Symptom: System Will Not Operate In Either Direction
Fault - Logic Troubleshooting

17
Model 70160
Diagram Action Step Comments
1 Inspect External Control Linkage for:
a. misadjustment or disconnection
b. binding, bending or breakage
c. misadjusted, damaged or broken neutral return spring
2 Inspect Servo Control Valve for: (if used)
a. proper inlet pressure
b. misadjusted, damaged or broken neutral return spring
c. galled or stuck control spool
d. galled or stuck servo piston
3 Inspect System Relief Valves* for:
a. improper pressure relief setting
b. damaged or broken spring
c. valve held off seat
d. damaged valve seat
4 Check Oil Level in Reservoir:
a. consult owner/operators manual for the proper type
fluid and level
5 Inspect Heat Exchanger for:
a. obstructed air flow (air cooled)
b. obstructed water flow (water cooled)
c. improper plumbing (inlet to outlet)
d. obstructed fluid flow
6 Inspect Heat Exchanger Bypass Valve for: (if used)
a. improper pressure adjustment
b. stuck or broken valve
7 Inspect Pump Bypass Valve for: (if used)
a. held in a partial or full open position
8 Inspect Inlet Screen or Filter for:
a. plugged or clogged screen or filter element
b. obstructed inlet or outlet
c. open inlet to charge pump
9 Check System Pressure:
a. See figure 60 for location of pressure gauge installation.
b. consult owner/operators manual for maximum system
relief valve settings
10 Check Charge Pressure:
a. See figure 60 for location of pressure gauge installation.
b. consult owner/operators manual for maximum charge
relief valve settings
11 Inspect Charge Relief Valve for:
a. improper charge relief pressure setting *
b. damaged or broken spring
c. poppet valve held off seat
12 Inspect Motor for:
a. disconnected coupling
13 Inspect Charge Pump for:
a. broken or missing drive key
b. damaged or missing o-ring
c. excessive gerotor clearance
d. galled or broken gerotor set
* System/Charge Relief Valve Pressure Settings for Eaton’s
Variable Displacement Controlled Piston Pumps
Inlet Vacuum 6 inHg max.
Case Pressure 25 PSI maximum
Charge Pressure 100 to 150 PSI Standard
200 to 250 PSI Optional
250 to 300 PSI Optional
System Pressure 5000 PSI maximum
3000 PSI continuous
The high pressure relief valves are all factory preset and
cannot be readjusted.
The pressure setting and assembly number is stamped on
each high pressure relief valve cartridge.
Valve Identification Example:
32060-IA 5000
Relief Valve Setting
Relief Valve Assembly Number
Fault - Logic Troubleshooting

18
Model 70160
When starting a new or rebuilt transmission system, it is
extremely important to follow the start-up procedure. It
prevents the chance of damaging the unit which might occur if
the system was not properly purged of air before start-up.
1After the transmission components have been properly
installed, fill the pump housing at least half full with filtered
system oil. Connect all hydraulic lines and check to be sure
they are tight.
2Install and adjust all control linkage.
3Fill the reservoir with an approved oil that has been filtered
through a 10 micron filter. Refer to Eaton Hydraulics
Technical Data Sheet number 3-401 titled Hydraulic Fluid
Recommendations.
4For Gasoline engines or L.P. engines remove the coil wire
and turn the engine over for 15 seconds. For Diesel engines
shut off the fuel flow to the injectors and turn the engine
over for 15 seconds.
5Replace the coil wire or return the fuel flow to the injectors.
Place the transmission unit in the neutral position, start the
engine and run it at a low idle. The charge pump should
immediately pick up oil and fill the system. If there is no
indication of fill in 30 seconds, stop the engine and
determine the cause.
6After the system starts to show signs of fill, slowly move
pump swashplate to a slight angle. Continue to operate
system slowly with no load on motors until system
responds fully.
7Check fluid level in the reservoir and refill if necessary to
the proper level with an approved filtered oil.
8Check all line connections for leaks and tighten if
necessary.
The machine is now ready to be put into operation.
Frequent filter changes are recommended for the first two
changes after placing the machine back into operation. Change
the first filter in 3-5 hours and the second in approximately 50
hours. Routinely scheduled filter changes are recommended
for maximum life of the hydraulic system.
Start-up Procedure

19
Model 70160