Parker PGP300 Series User manual

Pump & Motor Division
Vocational Truck Pump Program Catalog
Pump & Motor Division
PGP/PGM 300 Series
Service Manual

II
Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
FAILURE OR IMPROPER SELECTION OR IMPROPER USE OF THE PRODUCTS AND/OR SYSTEMS DESCRIBED HEREIN OR RELATED ITEMS CAN CAUSE DEATH, PERSONAL
INJURY AND PROPERTY DAMAGE.
This document and other information from Parker Hannin Corporation, its subsidiaries and authorized distributors provide product and/or system options for further investigation by
usershaving technical expertise. It is important that you analyze all aspects of your application and review the information concerning the product or system in the current product
catalog. Due to the variety of operating conditions and applications for these products or systems, the user, through its own analysis and testing, is solely responsible for making the
the products and systems and assuring that all performance, safety and warning requirements of the application are met.
The products described herein, including without limitation, product features, specications, designs, availability and pricing, are subject to change by Parker Hannin Corporation and
its subsidiaries at any time without notice.
WARNING — User Responsibility
Offer of Sale
The items described in this document are hereby offered for sale by Parker Hannin Corporation, its subsidiaries or its authorized distributors. This offer and its acceptance are governed
by the provisions stated in the “Offer of Sale”.
© Copyright 2020, Parker Hannin Corporation, All Rights Reserved

III
Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
Table of Contents
General Information ...........................................................................................................................1-4
Single Pump / Multiple Pump............................................................................................................ 1
Use Genuine Parker Replacement Parts ......................................................................................... 2
Tool List ............................................................................................................................................3-4
Exploded View ....................................................................................................................................... 5
Bill of Materials...................................................................................................................................... 6
Disassembly Instructions ................................................................................................................7-11
Assembly Instructions ...................................................................................................................12-18
Guidelines of Acceptable Wear.....................................................................................................19-20
Fluid Recommendations................................................................................................................ 21-23
Offer of Sale ....................................................................................................................................27-28

1
Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
PGP/PGM 300 Series
Gear Pumps & Motors Service Manual
Catalog HY13-PMD300-SM/US
General Information
Single Pump
Multiple Pump
Cast Iron Housing
Case Hardened Gears
SAE 2 or 4 Bolt
Mounts
SAE Split Flange and ORB Ports
Low Friction Bushing Coating
High Temperature Seals
Internal Passages Constantly Lubricates Bushings
Long Shaft Journals – Superior Bushing Surface
Large Passages for Better Pump Feed
Balanced Thrust Plates Minimize Friction & Leakage
Outboard Bearing offers Load Support for Output Shaft
One Piece Drive Shaft & Gear

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Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
Catalog HY13-PMD300-SM/US
General Information
Use Genuine Parker Replacement Parts
These service instructions will familiarize you with Parker's single and multiple pumps, their component parts, the relative
position of each part proper methods for assembly or disassembly of the units
To facilitate the repair of these units, and before any work is done, we suggest that you rst read all of the steps used in
disassembly and assembly.
Dirt is the enemy of any hydraulic system. The rst requirement of good maintenance of hydraulic equipment is cleanliness.
MAKE SURE YOU DISASSEMBLE AND ASSEMBLE YOUR HYDRAULIC EQUIPMENT IN A CLEAN AREA.
The pictures show Model PGP365. Notes in the text cover variations between this unit and the other models.
It is important to airblast all parts and wipe them with a clean, lintless cloth before assembly.
USE CAUTION IN GRIPPING ALL PARTS IN THE VISE TO AVOID DAMAGING MACHINED SURFACES
A pump must be driven in the direction of rotation for which it was built; otherwise, the pressure will blow the shaft seal.
Check the exploded view and notes at right for proper direction of rotation.
Parker’s Replacement Parts
Parker’s replacement parts are of original equipment standards. For assured quality of material and workmanship, and for
compatibility in assembly, USE ONLY GENUINE PARTS.
Check all replacement parts before installing them to be certain that they were not damaged in shipment.

3
Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
Catalog HY13-PMD300-SM/US PGP/PGM 300 Series
Gear Pumps & Motors Service Manual
Tool List
Arbor press Bearing puller (Owatonna Tool Co. M D - 956 or equivalent)
Awl Deburring tool (an old le with cutting teeth ground off)
1-1/2" Dia. steel ball No. 3 non-hardening sealant or equivalent
Clean, lintless cloths Permatex Aviation Form-A-Gasket™
Machinist’s hammer Medium grit carborundum stone
Soft hammer Scale (1/32" or 1/64" graduations)
Oil and grease Vise with 6" minimum opening
Snap ring pliers Bushing remover tool (See A)
Prick punch Seal removal tool (See B)
Small screw driver Bushing installation tool (See C)
Torque wrench Special steel sleeve (See D)
Bar for lip seal installation:
PGP/PGM315 use 1-5/8" dia. x 2" bar PGP/PGM350 use 2-1/2" dia. x 2" bar
PGP/PGM330 use 1-3/4" dia. x 2" bar PGP/PGM365 use 2-1/2" dia. x 2" bar
Bushing Puller: The bushings may be removed from their bores, using blind hole collet-type bushing pullers similar to
those manufactured by Owatonna Tool Co. The table illustrates the modications necessary to adapt the OTC collets
to this task. Equivalent pullers from other suppliers may be modied in similar fashion.
Pump/Motor A B C Make from
OTC Collect No.
PGP/PGM 315 .900"
.800"
.800"
.790"
.100"
.090" 33863
PGP/PGM 330 .980"
.970"
.875"
Ref.
.100"
.090" 33863
PGP/PGM 350 1.122"
1.122"
1.000"
0.990"
.072"
.052" 33864
PGP/PGM 365 1.382"
1.372"
1.250"
1.250"
.100"
.120" 33865
A
Typical Collet
.015" R Maximum
C
B
A
Seal Removal Tool
Easily made from an old screw driver. Heat the tip and bend as shown. Grind the tip to t the notch behind the shaft
seal.
B
1/4"
Catalog HY13-PMD300-SM/US
General Information

4
Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
Catalog HY13-PMD300-SM/US
General Information
Special Steel Sleeve
The special steel sleeve is used to insert the drive shaft through the lip seal without damage and can be made from bar
stock:
PGP/PGM315: Use a 1" dia. x 3-1/8" bar
PGP/PGM330: Use a 1-1/8" dia. x 4-5/8" bar or
PGP/PGM330: Use a 1-1/4" dia. x 4-5/8" bar
PGP/PGM350: Use a 1-3/8" dia. x 4-5/8" bar
PGP/PGM365: Use a 1-1 /2" dia. x 4-5/8" bar
The drawing and chart give details for making this special tool.
Bushing Installation Tool: A.I.S.I 8620 Bearing Quality Steel Heat Treated
Pump/Motor A B C
Radius D Dia. E Dia. F°
Chamfer
PGP/PGM 315 1-7/8" 3" 9/16" .944" + .000"
- .002" .885" + .000"
- .002" .050" x 60°
PGP/PGM 330 3-3/8" 4-1/2" 9/16" 1.065" + .000"
- .002" 1.002" + .000
- .002" .015" x 45°
PGP/PGM 350 3-3/8" 4-1/2" 9/16" 1.290" + .000"
- .002" 1.250" + .000"
- .002" .015" x 60°
PGP/PGM 365 3-3/8" 4-1/2" 9/16" 1.377" + .000"
- .002" 1.250" + .000"
- .002" .015" x 60°
All external surfaces must be free of scratches and burrs.
D
C
Pump/Motor A B C Dia. D Dia.
PGP/PGM 315 2.312" 1.15" .937" +.000"
- .002" 1.250
PGP/PGM 330 3.000" 1.47" 1.054" +.000"
- .002" 1.250
PGP/PGM 350 3.000" 1.47" 1.282" +.000"
- .002" 1.625
PGP/PGM 365 3.000" 1.73" 1.492" +.000"
- .002" 1.750
A
.06" .06"
30°
30°
Grind Relief Allowable
B
C
D
B
A
E
F°
C Radius 1/4" Hole Drill Through
D

5
Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
PGP/PGM 300 Series
Gear Pumps & Motors Service Manual
Catalog HY13-PMD300-SM/US
Exploded View
1
3
2
4
5
7
6
8
10
9
11
12
13
12
7
6
8
14
7
10
11
13
8
6
5
12
5
15
6
8
16
11
7
12
5
12
18
17
20
19

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Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
PGP/PGM 300 Series
Gear Pumps & Motors Service Manual
Catalog HY13-PMD300-SM/US
Bill of Materials
ITEM DESCRIPTION
1 Snap Ring
2 Outboard Bearing
3 Lip Seal, Shaft Seal
4 Shaft End Cover, Flange
5 Bushing
6 Backup Seal
7 Channel Seal
8 Thrust or Pressure Plate
9 Gear Shaft, Drive Gear
10 Driven Gear, Idler Gear
11 Square Seal, Section Seal
12 Dowel Pin
13 Gear Housing, Body
14 Bearing Carrier
15 Connecting Shaft
16 Drive Gear
17 Port End Cover, Rear Cover
18 Stud, Cap Screw, Fastener
19 Washer
20 Hex Nut

7
Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
Catalog HY13-PMD300-SM/US PGP/PGM 300 Series
Gear Pumps & Motors Service Manual
Disassembly Instructions
CAUTION:
1. If prying off sections becomes necessary, take extreme care not to mar or damage machined surfaces. Excessive force
while prying can result in misalignment and seriously damage parts.
2. If parts are difcult to t during assembly, tap gently with a soft hammer. (Never use an iron hammer).
3. Gears are closely matched, therefore they must be kept together as sets, avoid touching gear journals when removed
from a unit. Handle with care to avoid damage to the journals or teeth.
4. Never hammer bushings into bores. Use an arbor press.
1) Place the pump in a vise with the drive shaft
pointing down (Fig. 1). Match-mark all sections.
Be sure to align these marks when reassembling.
DO NOT GRIP ON OR NEAR ANY MACHINED
SURFACES DURING ASSEMBLY OR
DISASSEMBLY.
Figure 1
2) Remove four bolts and cap screws on single units
or the 4 hex nuts, studs and washers of multiple
units (Fig. 2). Use an impact driver in a cross-
pattern. Inspect threads and cap screws for wear.
Figure 2
3) Lift off the port end cover and look at underside
for any damage (Fig. 3). If prying is necessary,
be careful not to damage the machined surfaces.
Dowel pins will remain in either the port end cover
or the gear housing. Make sure they are rmly in
place and not missing for reinstallation.
Figure 3
Start Disassembly

8
Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
Disassembly Instructions
4) Remove the thrust plate (Fig. 4). Examine both sides
for wear and replace if necessary.
See Step 12, on page10, for examples of thrust
plate wear.
Figure 4
5) Match mark gears in center (Fig. 5). This will ensure
the pump is correctly reassembled.
Figure 5
6) Carefully remove idler gear rst (Fig. 6). Avoid
tapping the gear teeth together or against other
hardened surfaces.
Figure 6
7) Next, remove the drive shaft. Keep these gears
together because they are a matched set. Examine
and replace if necessary (Fig. 7). (See pages 19-20)
Figure 7

9
Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
Catalog HY13-PMD300-SM/US PGP/PGM 300 Series
Gear Pumps & Motors Service Manual
Disassembly InstructionsDisassembly Instructions
8) For multiple assemblies only:
Remove the thrust plate from the bearing carrier.
Examine and replace if necessary.
9) Lift or pry off the section gear housing. If prying is
necessary, take care not to damage machined
surfaces (Fig. 8). Examine and replace if necessary
(See pages 19-20).
Figure 8
10) Remove section seal and examine for damage.
Insert seal back into the bottom of the gear housing
for reassembly (Fig. 9)
Figure 9
11) Inspect gear housing for damage/cutout at the gear
bore (Fig. 10). See pages 19-20 for wear guide.
Example of excessive cutout on gear housing,
circled in yellow (Fig. 11).
Figure 10
Figure 11

10
Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
Disassembly InstructionsDisassembly Instructions
12) Remove thrust plate and examine for wear.
Wear on thrust plate will reveal exactly what
happened to the thrust plate (Fig. 12).
Examples of damaged plates (Fig. 12a & 12b).
Figure 12
Figure 12a
Figure 12b
13) Examine top of Shaft End Cover as well as bushings
and lip seal for wear or damage. Ensure that they
are free of debris (Fig. 13).
Figure 13

11
Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
Catalog HY13-PMD300-SM/US PGP/PGM 300 Series
Gear Pumps & Motors Service Manual
Disassembly Instructions
14) Examine bottom of Shaft End Cover (Fig. 14).
Figure 14
If your pump is NOT equipped with an outboard
bearing, skip to #17.
15) Outboard bearing pumps ONLY:
Remove snap ring (Fig. 15). Place the shaft end
cover in the vise with the mounting face up. Remove
the snap ring with snap ring pliers. If a unit is
equipped with a spiral-lock retaining ring, remove
with a small screwdriver or awl.
Figure 15
16) Outboard bearing pumps ONLY:
Remove outboard bearing (Fig. 16). Use a bearing
puller to remove bearing.
Figure 16
17) Remove lip seal (Fig. 17). Grip the shaft end cover in
a vise with the mounting face down. Remove double
lip seal by inserting the special seal removal tool
(see Tool List on page 3) into the notch between the
double lip seal and the shaft end cover. Tap the seal
out and discard. Remove and discard all rubber and
polymer seals.
Figure 17

12
Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
Assembly Instructions
Start Assembly
1) Before starting assembly, clean all machined surfaces and
make sure they are free of debris.
Figure 1
2) Prep new lip seal by coating the outer edge of the seal
with Aviation Gasket sealant, also coat the lip seal cavity
(Fig. 1 & 2).
Figure 2
3) Replace lip seal (Fig. 3 & 4). With the metal side of the lip
seal up, press it into the mounting ange side of the shaft
end cover with an arbor press and bar (see Tool List on
page 4). Be careful not to damage the lip of the seal.
Press in until ush with the recess. Wipe off excess sealant.
Figure 3
Figure 4

13
Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
Catalog HY13-PMD300-SM/US PGP/PGM 300 Series
Gear Pumps & Motors Service Manual
Assembly Instructions
4) If the unit is equipped with an outboard bearing, install
bearing with arbor press then install new snap ring
(Fig. 5, 6, & 7).
Figure 5
Figure 6
5) Assemble the snap ring (Fig. 7 & 8) . Using snap ring plyers,
seat new snap ring on top of bearing and lip seal.
Figure 7
Figure 8

14
Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
Assembly Instructions
6) Mount shaft end cover facing down in a vise and
examine checks and/or plug (Fig. 9) . Make sure checks
and/or plug are tightly in place. They might still be inside
the shaft end cover from disassembly. Replacement
is necessary only if parts are damaged. Remove with
screwdriver.
Figure 9
7) Verify dowel pins are in place in any new castings (Fig. 10) .
Examine all of the dowels. Before inserting, make certain
that the hole is clean and free from burrs. Gently start the
pin straight into the hole and tap lightly with a soft-faced
hammer.
Figure 10
8) Re-afx or replace section seal (Fig. 11). Verify both
sides of the section seal are free of debris. If replacing
section seal, grease the new seal then insert rmly into the
grooves on both sides of the gear housing.
Figure 11
9) Place gear housing over shaft end cover and dowels,
lining up witness marks (Fig. 12) .
Tap it with a soft hammer until it rests tightly against the
shaft end cover. Be careful not to pinch the gasket seal.
Also be sure that the large rounded core is on the inlet
side.
Figure 12

15
Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
Catalog HY13-PMD300-SM/US PGP/PGM 300 Series
Gear Pumps & Motors Service Manual
10) Assemble new sealing parts in pressure plate and verify
orientation.
The sealing parts can be xed with grease (see below for
steps to install sealing parts correctly).
i. Turn the pressure plates so the seal groove faces up.
ii. Place the soft black into the seal groove with the at
side down.
iii. Place the hard nylon back-up seal, at side up, into
the groove on top of the rubber seal.
Pump Pressure Plate - Back Side (Fig. 13)
Pump Pressure Plate - Seals in Place (Fig. 14)
Motor Pressure Plate - Back Side (Fig. 15)
Motor Pressure Plate - Seals in Place (Fig. 16)
The proper seal installation is very important. If these
seals are assembled upside down, they will most likely
fail in a short period of time under system pressure.
Figure 13 - Pump Pressure Plate - Back Side
Figure 14 - Pump Pressure Plate - Seal in Place
Figure 15 - Motor Pressure Plate - Back Side
Figure 16 - Motor Pressure Plate - Seal in Place

16
Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
11) Place bottom thrust plate into shaft end cover (Fig. 17).
Orientation is rotation sensitive for pumps and the seals
should be pointed down and facing the high-pressure
side of the pump, the pressure port.
Gently tap the thrust plate with a soft mallet until it
touches the shaft end cover.
Figure 17
12) Insert a seal guide to protect drive shaft (Fig. 18).
Coat seal guide with grease and place into pressure
plate.
Figure 18
Example of a shaft seal guide being used to protect a
gear bearing bores to engage the dowels and to move
parts together in the nal seating (Fig. 19).
Figure 19
13) Place drive shaft through seal guide and in place in
thrust plate (Fig. 20). Press it down while turning drive
shaft from the bottom to move witness marks back into
center and the integral gear rests against the thrust
plate. Avoid damaging the lip seal. The seal guide will
drop out of the bottom of the pump. Squirt clean oil over
the gears.
Figure 20

17
Parker Hannifin Corporation |Pump & Motor Division |Kings Mountain, NC
WARNING: This product can expose you to chemicals including lead or DEHP which are known to the state of California to cause cancer,
birth defects, and other reproductive harm. www.p65warnings.ca.gov
Catalog HY13-PMD300-SM/US PGP/PGM 300 Series
Gear Pumps & Motors Service Manual
Assembly Instructions
14) Insert idler gear (Fig. 21). Line up witness marks and
push down.
Figure 21
15) Install top thrust plate (Fig. 22). Make sure the seal
in the thrust plate is facing up over the gear journals
and towards the housing bore. The at side of the seal
should face up with the relief groove facing the outlet
side.
Figure 22
16) Place port end cover over the gear journals
(Fig. 23). Examine port-end cover that is free of any
debris that might get stuck in the section seal. Align
the dowels with the holes in the mating casting. Being
careful not to pinch the gasket-seal, tap the port end
cover lightly in the center between bearing bores to
engage the dowels and to move parts together in the
nal seating and it touches the section seal surface.
Make sure witness marks line up.
Figure 23
17) Insert and hand tighten bolts and washers (Fig. 24).
Finish tightening with an impact gun in a cross pattern.
Figure 24