OilGear A2 Series Operating instructions

THE OILGEAR COMPANY
905 South Downing Street
Fremont, NE 68025 USA
www.oilgear.com
Issued: May 2019
PUMP SERVICE MANUAL
Bulletin 948034A
Bulletin 948034A
Figure 1. Typical Oilgear “PVG” Open Loop Pump
PURPOSE OF INSTRUCTIONS
These instructionswillsimplifythe installation,
operation, maintenance andtroubleshooting of
Oilgear type “PVG” pumps.
Become familiar withthe construction, principl
eo
f
operation and characteristicsofyour pumpto help
youattainsatisfactory performance, reduce shut-
down and increasethe pump'sservice life.Some
pumps have been modified from those described in
this bulletin and other changesmay be made
without notice.
REFERENCE MATERIAL
Fluid Recommendations........................................................................................................................... Bulletin 90000
Contamination Evaluation Guide ............................................................................................................ Bulletin 90004
Filtration Recommendations..................................................................................................................... Bulletin 90007
Piping Information .................................................................................................................................... Bulletin 90011
Installation of Vertically Mounted Axial Piston Units................................................................................. Bulletin 90014
PVG Open Loop Pumps, Sales ............................................................................................................Bulletin 47019-K
Pump Control Instructions, Series A1
“P-1NN” Single Pressure Compensator ................................................................................................ Bulletin 948675
“P-1NN/F” Single Pressure Compensator w/Load Sense ..................................................................... Bulletin 948676
“P-1NN/H” Single Pressure Compensator w/H.P. Limiter ..................................................................... Bulletin 948677
“P-1NN/G” Horsepower Limiter w/Load Sense .................................................................................... Bulletin 948678
“P-1NN/K” Single Pressure w/Load Sense, Minimum Standby ............................................................ Bulletin 948683
“P-1NN/L” Single Pressure w/HP Limiter & Load Sense, Minimum Standby ....................................... Bulletin 948684
“P-2” Dual Pressure Compensator ...................................................................................................... Bulletin 948679
“P-C & P-K” Single Pressure - Soft Start ............................................................................................. Bulletin 948680
“P-CNN/H & P-KNN/H” Single Pressure - Soft Start w/H.P. Limiter...................................................... Bulletin 948681
“P-2NN/H” Dual Pressure Compensator w/H.P. Limiter........................................................................ Bulletin 948682
“P-E” Electronic Displacement Control ................................................................................................ Bulletin 948690
“P-E/F” Electronic Displacement Control w/Load Sense ..................................................................... Bulletin 948691
OILGEAR TYPE “PVG” PUMPS
180 (SERIES A2)
SERVICE INSTRUCTIONS

© 2019 THE OILGEAR COMPANY - ALL RIGHTS RESERVED Bulletin 948034A
2
Bulletin 948034A
PUMP SERVICE MANUAL
Table of Contents
Safety First ..........................................................................................................................3 - 5
Preparation and Installation.................................................................................................6 - 7
Principle of Operation..........................................................................................................8 - 9
Specications .........................................................................................................................10
Troubleshooting...................................................................................................................... 11
Testing and Adjusting / Disassembly ..............................................................................12 - 13
Rotating Group / Inspection.............................................................................................14 - 16
Assembly.........................................................................................................................16 - 18
PVG Pump Torques Numbers & Descriptions........................................................................ 19
Parts List.................................................................................................................................20
O-Ring Seals Item Number List.............................................................................................. 21
Service Kits List...............................................................................................................22 - 23
Parts Exploded Views......................................................................................................24 - 27
Spare Parts Availability........................................................................................................... 28

© 2019 THE OILGEAR COMPANY - ALL RIGHTS RESERVED 3
Bulletin 948034A
Bulletin 948034A
Safety First
PUMP SERVICE MANUAL
Read and understand this entire instruction sheet
be
fore repairing or adjusting your Oilgear product.
Those
who use and maintain this equipment must
be
thoroughly trained and familiar with the product.
If
incorrectly used or maintained, this product and
its equipment can cause se
vere injury.
SAFETY SYMBOLS
The
following signal words are used in this
inst
ruction sheet to identify areas of concern where
yo
ur safety may be involved. Carefully read the text
and
observe any instructions provided to ensure
yo
ur safety.
THIS SIGNAL WORD INDICATES AN
IMMINENTLY HAZARDOUS SITUATION
WHICH, IF NOT AVOIDED, WILL RESULT IN
DEATH OR SERIOUS INJURY.
This signal word indicates a potentially
hazardous situation which, if not avoided,
could result in death or serious injury.
This signal word indicates that a potentially
hazardous situation exists which, if not
avoided, may result in damage to
equipment or minor personal injury.
While not directly relevant to the topic being
discussed, the NOTE is used to emphasize
information provided, or provide additional
information which may be of benefit.
This service information is designed for
the maintenance of your Oilgear product.
It contains the information on the correct
procedures determined by Oilgear for the
safe manner of servicing. Always keep
this instruction sheet in a location where it
is readily available for the persons who
use and maintain the product. Additional
copies of this instruction sheet are
available through the Oilgear Company.
Or visit our website: www.oilgear.com.
Please contact us if you have any
questions regarding the information in
this instruction bulletin.
The cleanliness of working on this pump or
the hydraulic system is extremely
important to the safety and reliability of the
pump and the system. Always make sure
the fittings are clean on the outside before
removing them from their connections, are
capped and plugged when removed and
placed in a clean rag or container until they
are reinstalled.
Some service operations may require
special tools or equipment. If you require
information on these items, please contact
Oilgear before attempting these repairs
and service operations.
Read, understand, and follow the safety
guidelines, dangers, and warnings
contained in this instruction sheet to
promote reliable operation and prevent
serious personal injury.
DO NOT attempt to service this machinery
in an environment where safety regulations
are not established and in place.
DO NOT operate the hydraulic system if a
leak is present. Serious injury may result.
Hydraulic systems operate under very high
pressure. Hydraulic fluid escaping from a
pressurized system can penetrate
unprotected body tissue. DO NOT inspect
for hydraulic leaks with bare hands or other
exposed body parts. As a minimum, wear
leather gloves prior to inspecting for leaks
and use cardboard or wood. If leaks are
present, relieve pressure and allow system
to cool prior to servicing. If injured by
escaping hydraulic oil, contact a physician
immediately. Serious complications may
arise if not treated immediately. If you have
questions regarding inspecting for
hydraulic leaks, please contact Oilgear
prior to servicing.
DANGER
! !
!WARNING
CAUTION
NOTE
!WARNING
NOTE
!WARNING
!WARNING
!WARNING
!WARNING
!WARNING

© 2019 THE OILGEAR COMPANY - ALL RIGHTS RESERVED
4
Safety First
Bulletin 948034A
Bulletin 948034A
PUMP SERVICE MANUAL
Hydraulic
hoses and tubing must be
inspected
on a daily basis for leaks, cuts,
abrasions,
damage and improper
cl
earance along any mounting frame for
hidden
damage before the unit is put into
servic
e. Replace damaged hoses or hoses
y
ou suspect are damaged before the
system is returned to service! Hoses m
ust
be
replaced every two years. Failure to
pr
operly inspect and maintain the system
ma
y result in serious injury.
Hydraulic
systems are hot. DO NOT
TO
UCH! Serious personal injury may
result
from hot oil. When you have
completed
working on the hydraulic
system,
thoroughly clean any spilled oil
fr
om the equipment. Do not spill any
hy
draulic fluids on the ground. Clean any
hy
draulic fluids from your skin as soon as
y
ou have completed maintenance and
repair
s. Dispose of used oil and system
filter
s as required by law.
Use
correct hoses, fittings, and adapters
with
the correct SAE rating when
replacing
hoses to prevent possible
serious
injury. Always replace hoses,
fittings,
and adapters with replacements
that
have a proper, suitable, working
pressure
rating. Replacement hoses must
be
of the correct length and must comply
with
the hose manufacturerʼs and
Oil
gearʼs installation guidelines and
recommendations.
Hydraulic
hoses have the SAE ratings
marked
on the hose to assist you in
selecting
the correct hose. The same
manufacturer
must supply any replacement
hy
draulic hoses and fitting assemblies. As
an e
xample: Brand “X” hose and brand “Y”
fitting
will not normally be compatible. No
“T
wist” is allowed in the hydraulic hoses.
“T
wist” may result in premature hose
failur
e. This can cause serious injury.
Please contact Oilgear
for assistance when
required.
Hydraulic cylinders can be holding
a
function in a certain position when the
pump is OFF. An example of this is
a
function being held in the lift or partial lift
position by the cylinders. If a hydraulic
line is removed or the hydraulic circuits or
controls are being worked on, gravity may
allow the function being held in position to
drop. All workers and personnel must
remain clear of these areas when working
on or operating the hydraulic system.
Block and secure all devices and
functions which apply before beginning
work or operation. Failure to comply with
this can result in serious injury or death.
Any hydraulic pipe which is replaced must
conform to SAE J1065 specifications. If
incorrect hydraulic pipe is installed, the
hydraulic system may fail, causing
serious injury. Damaged or leaking
fittings, pipes or hoses must be replaced
before the system is returned to service.
DO NOT heat hydraulic pipe. The carbon
content of this steel tube is such that if
heated for bending, and either water or air
quenched, the pipe may lose its ductility
and thereby be subject to failure under
high pressure conditions. Serious injury
can result. Damaged or leaking pipes must
be replaced before the system is returned
to service. Please contact Oilgear if you
require assistance or have questions.
All hydraulic pressure must be reliev
ed
from the hydraulic system prior to remo
ving
any components from the system. To
relieve the hydraulic pressure from t
he
hydraulic system, turn off the motor and
operate the control panel with the key in the
ON position. Failure to comply can result in
serious injury. If you have any questions
concerning relieving the h
ydraulic pressure
from the system, please contact Oilgear.
!WARNING
!WARNING
!WARNING
!WARNING
!WARNING
!WARNING
!WARNING
!WARNING

© 2019 THE OILGEAR COMPANY - ALL RIGHTS RESERVED 5
Bulletin 948034A
Bulletin 948034A
Safety First
PUMP SERVICE MANUAL
Hydraulic
components can be heavy. Use
caution
while lifting these components.
Serious
personal injury can be avoided
with pr
oper handling of the components.
Please
contact Oilgear if you require
assistance,
when performing hydraulic
test
procedures, use the proper hydraulic
gauges.
Installing an incorrect test gauge
could
result in serious injury if the gauge
fails.
Use properly rated hydraulic hoses
to
allow the test gauge to be read away
fr
om moving parts and functions.
Increasing
hydraulic pressure beyond the
recommendations
may result in serious
dama
ge to the pump and system or
serious
personal injury and may void the
Oil
gear Warranty. If you have questions
concerning
hydraulic pressures or testing
pr
ocedures, please contact Oilgear before
attempting
the test procedures or making
adjustments
.
An
Oilgear pump must not be modified in
an
y way without authorization from
Oil
gear. Modifications may not comply
with
safety standards, including ANSI
saf
ety standards, and may result in
serious
personal injury. Please contact
Oil
gear if you require assistance.
DO
NOT enter under hydraulic supported
equipment
unless they are fully supported
or
blocked. Failure to follow this procedure
can result in serious injury or death.
Any Oilgear pump safety decals must be
replaced anytime they are damaged,
missing, or cannot be read clearly. Failure
to have proper decals in place can result
in serious injury or death. (If you require
safety decals, please contact Oilgear for
replacement safety decals, at no charge.)
Be sure everyone is clear of the area
around the hydraulic system before
operating after servicing. Remain attentive
at all times when operating to check your
work until you are completely sure it is
safe to return to service. Failure to heed
this warning may result in serious
personal injury or death.
Wear the proper protective clothing when
operating, servicing or maintaining the
hydraulic system or the Oilgear pump. Wear
the correct protective gear, safety glasses,
gloves, and safety shoes. Serious injur
y
can result without proper protective gear.
Make sure to keep hands and feet and
other parts of your body clear of revolving
or moving parts. Failure to comply can
cause serious injury.
DO NOT wear watches, rings, or jewelry
while working with electrical and
mechanical equipment. These items can
be hazardous and can cause serious and
painful injuries if they come into contact
with electrical wires, moving parts, or
hydraulic equipment.
!WARNING
!WARNING
!WARNING
!WARNING
!WARNING
!WARNING
!WARNING
!WARNING
!WARNING
!WARNING

© 2019 THE OILGEAR COMPANY - ALL RIGHTS RESERVED Bulletin 948034A
6
Bulletin 948034A
PUMP SERVICE MANUAL
PREPARATION AND
INSTALLATIO
N
MOUNTIN
G
Pump
Without Reservoir - The pump can be
mounted
in any position. But, the recommended
mounting
position is with the drive shaft on a
ho
rizontal plane and the case drain port 1 on the
top
side. Secure the pump to a rigid mounting
surf
ace. Refer to the referenced Oilgear Piping
In
formation Bulletin 90011.
Pump
With Reservoir - These pumps are usually
fully
piped and equipped. It may be necessary to
connect
to a super-charge circuit when used.
Mount
reservoir on level foundation with the
rese
rvoir bottom at least six inches above floor
le
vel to facilitate fluid changes.
PIPING AND FITTING
S
Re
fer to the referenced Oilgear Piping Information
Bulletin 90011 and individual circuit diagr
am before
connecting
the pump to the system. Inlet velocity
mu
st not exceed 5 fps (1,5 mps). Inlet should be
unrestricted and ha
ve a minimum of fittings.
DO NOT use an inlet strainer.
A
rrange line from “case drain” so the case remains
full of fluid (non-siphoning).
Case pressure must be
less
than 25 psi (1,7 bar). For higher case
pressure
s, special shaft seals are required; contact
our
Customer Service. Each drain line must be a
separate
line, unrestricted, full sized and
connected
directly to the reservoir below the lowest
fluid
level. Make provisions for opening this line
without draining (siphoning) reser
voir.
Running the pump in NEUTRAL position
(zero delivery) for extended periods
without a supercharge circuit can damage
the pump. The system and pump must be
protected against overloads by separate
high pressure relief valves. Install bleed
valve(s) at the highest point(s) in system.
POWER
Power is required in proportion to volume and
pressure used. Motor size recommendations for
specific applications can be obtained from The
Oilgear Company. Standard low starting torque
motors are suitable for most applications.
DO NOT start or stop unit under load
unless system is approved by Oilgear. It
may be necessary to provide delivery
bypass in some circuits.
DRIVE
Verify rotation direction plate on the pump's housing
.
Clockwise pumps must be driven clockwise an
d
counterclockwise pumps must be driv
en
counterclockwise. Use direct drive coupling. Size
and install coupling per manufacturer's instructions.
DO NOT drive the coupling onto the pump
drive shaft. If it is too tight, it may be
necessary to heat coupling for installation.
Refer to manufacturer's instructions.
Misalignment of pump shaft to driver's shaft should
not exceed 0.005 inches (0,13 mm) To tal Indicator
Readout (TIR) in any plane.
NOTE
!WARNING
CAUTION
CAUTION

© 2019 THE OILGEAR COMPANY - ALL RIGHTS RESERVED
Bulletin 948034A 7
Bulletin 948034A
PUMP SERVICE MANUAL
Ke
ep the fluid clean at all times to ensure long life
from
your hydraulic system. Refer to the referenced
Oilgear
Filtration Recommendations bulletin 90007
and
Oilgear Contamination Evaluation Guide
Bulletin
90004. Oilgear recommends use of a filter
in
the pressure or return line. Replace filter
element(s)
when the filter condition indicator
reaches
change area at normal fluid temperature.
Drain
and thoroughly clean filter case. Use
replacement
element(s) of same beta 10 ratio
(nor
mally a ratio of 4 with hydraulic oils).
FLUID COOLIN
G
FILTRATION
When
the pump is operated continuously at the
ra
ted pressure or frequently at peak load, auxiliary
cooling
of the fluid may be necessary. Fluid
temper
ature should not exceed limits specified in
the
referenced Oilgear Fluid Recommendations
Bulletin 90000
.
AIR BREATHER
On
most installations, an air breather is mounted
on
top of fluid reservoir. It is important for the
breather to be the adequate si
ze to allow air flow in
and
out of reservoir as fluid level changes. Keep
the
breather case filled to the “fluid level” mark.
A
bout once every six months, remove cover, wash
screen
in solvent and allow screen to dry, clean
and
refill case to level mark and install screen.
Re
fer to the manufacturer's recommendations.
FLUID, FILLING AND STAR
TING
RECOMMENDATION
S
Re
fer to instruction plate on the unit, reservoir,
machine
and/or reference, Fluid Recommendations
bu
lletin. Fire resistant fluids and phosphate ester
fluids
can be used in accordance with fluid
manu
facturer's recommendations.
1.
Pump all fluid into reservoir through a clean
(beta 10 ratio of 4 or more) filter. Fill reservoir
to, but not above, “high level” mark on the sight
gauge.
2.
Remove case drain line and fill pump case
with hydraulic fluid.
3.
Tu rn drive shaft a few times by hand with a
spanner wrench to make sure parts rotate.
To rque to turn drive shaft should be 9 to 24 ft•lb
(12 to 32 N•m).
With pump under “no load” or with pump control at
NEUTRAL:
4. Tu rn drive unit ON and OFF several times
before allowing pump to reach full speed. The
system can usually be filled by running the
pump and operating the control.
5. The fluid level in the reservoir should decrease.
Stop the pump. DO NOT allow the fluid level to
go beyond the “low level.” If the level reaches
“low level” mark, add fluid and repeat step.
With differential (cylinder) systems, the fluid
must not be above “high level” when the
ram is retracted or below “low level” when
extended. Bleed air from the system by
loosening connections or opening petcocks
at the highest point in the system. Close
connections or petcocks tightly when solid
stream of fluid appears.
CONSTRUCTION
SeeFigure 3.
A drive shaft (301) runs through the center line
of pump housing (001)and valveplate (401)
with the pump cylinderbarrel (101) splined to it.
A bearing (306) supports the outboard end of
the drive shaft and a bushing supports the
inboard end. (The bushingis part of valveplate
assembly.)
The pump cylinder barrel is carried in a
polymerous (journal type)
bearing (001).
The valve plate (401)has two crescent shaped
ports.
The pumping piston/shoe assemblies (102)in
the cylinder barrel are held against a
swashblock (201) by a shoe retainer (104).
The shoe retainer is held in position by the
fulcrum ball (103) which is forced outward by
theshoe retainer spring (105).
The spring acts againstthe pump cylinder
barrel, forcing it against the valve plate
while
also forcingthe piston shoes against the
swashblock.
The semi-cylindrical shaped swashblock limit
s
the piston stroke and can be swiveled in arc
shaped saddle bearings (204).
The swashblockisswiveled by a contro
l
(included in referenced material). Refe
rt
o
PRINCIPLE OF OPERATION
.
NOTE

© 2019 THE OILGEAR COMPANY - ALL RIGHTS RESERVED Bulletin 948034A
8
Bulletin 948034A
PUMP SERVICE MANUAL
PRINCIPLE OF OPERATION
The illustrations show the pump driven counter-
clockwise (left hand) from the top (plan) view.
Figure 2. Cut-away of a
Typical “PVG” Pump
PositionB, Pump During Full Delivery From
PORT B - Figure 3
Rotating the drive shaft (301) counter-clockwise
turns the splined cylinder, whichcontainsthe
pumping pistons(102).When the cylinderrotates,
thepistons move in and out within their bores as
the shoes ride against the angled (C) swashblock
(201).
As the cylinder rotates, the individual piston bores
are connected, alternately, to the crescent shaped
port A and port Bin the valve plate. While
connected to the suction port A, each piston moves
outward (OUT), drawing fluid from port Ainto the
piston bore until its outermost stroke (D) is
reached. At this point, the piston bore passes from
port Ato port B.
While rotating across the crescent port B, each
piston moves across the angled swashblock face
and then each piston is forced inward (IN). Each
piston then displaces fluid through the crescent to
portBuntil its innermost stroke (D) is reached. At
this point, the piston bore passes from the B to the
Acrescent again and the cycle is repeated.
Figure 3. Position B, Pump During Full Delivery From Port B
A
A
C
IN
OUT
AB
301
306
001 201
103
104 102
101 401
DSECTION A-A

© 2019 THE OILGEAR COMPANY - ALL RIGHTS RESERVED
Bulletin 948034A 9
Bulletin 948034A
PUMP SERVICE MANUAL
Position B/2, Pump During One Half Delivery
From PORT B - Figure 4
This illustration shows that the angle (E) of the
swashblock determines the length of the piston
stroke (F), (the difference between outermost and
innermost position) which determines the amount
of delivery from the pump. In this case, the stroke
angle (E) is one-half of the stroke, which means the
piston stroke is one-half and the pump delivery is
one-half.
Position N, Pump In Neutral, No Stroke, No
Delivery - Figure 5
Neutral position results when the control
centers the swashblock. The swashblock
angle (G) is now zero and swashblock face is
parallel to the cylinder face. There is no
inward or outward motion of the pump pistons
as piston shoes rotate around the swashblock
face. With no inward and outward motion or
no stroke (H),NEUTRALno fluid is being
displaced from the piston bores to the
crescents in the valve plate and there is no
delivery from pump ports.
Illustration reference numbers match
thepart item number in the parts list.
Figure 4. Position B/2, Pump During One Half Delivery From Port B
Figure 5. Position N, Pump In Neutral, No Stroke, No Delivery
Refer to SPECIFICATIONS
NOTE
A
A
EF
IN
OUT
AB
SECTION A-A
A
A
G
AB
NEUTRAL
NEUTRAL
HSECTION A-A

© 2019 THE OILGEAR COMPANY - ALL RIGHTS RESERVED Bulletin 948034A
10
Bulletin 948034A
PUMP SERVICE MANUAL
SPECIFICATIONS
Refer to reference material, pump control
material and individual application circuit
for exceptions.
Case pressure should be less than 25 psi (1,7 bar). For higher case pressure, consult factory.
Table 1. Nominal Performance Data with 150-300 SSU viscosity fluids.
All dimensions (without controls) are approximate. For detailed dimensions, contact
your Oilgear Representative.
Table 2. Nominal Dimensions without controls.
Refer to installation drawings for more detailed dimensions and port configurations.
NOTE
Unit
THEORETICAL
MAXIMUM
DISPLACEMENT
RATED
CONTINUOUS
PRESSURE
PEAK
PRESSURE
FLOW RATE at
1800 rpm rated
continuous pressure
and 14,7 psia (bar abs)
inlet condition
MAXIMUM
SPEED
POWER
INPUT at rated
continuous
pressure &
1800 rpm
in 3/revml/revpsi bar psibar gpml/mirpm hp kw
PVG 180 11.00 180,0 5000 344,8 5800 400,078.0 295,32400 260193,9
Unit LengthWidth Height Weight Face Mounting
inches mm inches mm inches mm lbs.kg
PVG 18015.1 383,3 8.4 213,48.9 226,1197*90SAE “D” 4 bolt
* Weight with "P-1NN" Control and thru shaft valve plate
.