Graco Power-Star B Series User manual

Instructions - Parts List
Power-Star™308391P
EN
Used to pump high volumes of petroleum and synthetic based oils. For professional use only.
Model No. 236754, Series B
1:1 Ratio Universal Pump and Reciprocator
Model No. 236752, Series B (Square Housings), Series C (Cylindrical Housings)
Reciprocator Only
1500 psi (10 MPa, 103 bar) Maximum Hydraulic Input Pressure
1500 psi (10 MPa, 103 bar) Maximum Fluid Outlet Pressure
Important Safety Instructions
Read all warnings and instructions in
this manual before using the equipment.
Save these instructions.
WARNING
This pump is designed to be used only in pumping
non-corrosive and non-abrasive oils and lubricants. Any
other use of the pump can cause unsafe operating
conditions and result in component rupture, fire, or
explosion, which can cause serious injury, including fluid
injection.
Model 236752,
Series B
Model 236752,
Series C Model 236754,
Series B

2 308391P
Contents
Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Pump Accessories . . . . . . . . . . . . . . . . . . . . . . . . 5
Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Hydraulic Power Supply. . . . . . . . . . . . . . . . . . . . 6
Hydraulic Components . . . . . . . . . . . . . . . . . . . . 7
Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Pressure Relief Procedure . . . . . . . . . . . . . . . . . . 8
Before Starting the Pump . . . . . . . . . . . . . . . . . . 8
To Start the Pump . . . . . . . . . . . . . . . . . . . . . . . . 8
Shutdown and Care . . . . . . . . . . . . . . . . . . . . . . . 9
Emergency Stop Procedure. . . . . . . . . . . . . . . . . 9
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Repair. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Intake Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Displacement Pump . . . . . . . . . . . . . . . . . . . . . . 14
Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Model 236752, Series B - Square Housings . . . 15
Model 236752, Series C - Cylindrical Housings. 17
Model 236754, Series B - Cylindrical Housings. 19
Technical Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Performance Chart . . . . . . . . . . . . . . . . . . . . . . . . . 21
California Proposition 65 . . . . . . . . . . . . . . . . . . . . 21
Graco Standard Warranty. . . . . . . . . . . . . . . . . . . . 22
IMPORTANT
The design of the Viscount II hydraulic pump upper and lower motor housings has been updated. This cylindrical
design replaces the square housing design previously used. There is no performance change associated with this
update.
If replacement of a square housing is necessary, both upper and lower housings should be converted to the
cylindrical design as it is not backwards compatible.
Unless otherwise specified in this manual, all Instructions apply to both Square and Cylindrical Series of Models.

Warnings
308391P 3
Warnings
The following warnings are for the setup, use, grounding, maintenance, and repair of this equipment. The
exclamation point symbol alerts you to a general warning and the hazard symbols refer to procedure-specific risks.
When these symbols appear in the body of this manual or on warning labels, refer back to these Warnings.
Product-specific hazard symbols and warnings not covered in this section may appear throughout the body of this
manual where applicable.
WARNING
FIRE AND EXPLOSION HAZARD
When flammable fluids are present in the work area, such as gasoline and windshield wiper fluid, be
aware that flammable fumes can ignite or explode. To help prevent fire and explosion:
•Use equipment only in well-ventilated area.
•Eliminate all ignition sources, such as cigarettes and portable electric lamps.
•Ground all equipment in the work area.
•Keep work area free of debris, including rags and spilled or open containers of solvent and gasoline.
•Do not plug or unplug power cords or turn lights on or off when flammable fumes are present.
•Use only grounded hoses.
•Stop operation immediately if static sparking occurs or you feel a shock. Do not use equipment until
you identify and correct the problem.
•Keep a working fire extinguisher in the work area.
SKIN INJECTION HAZARD
High-pressure fluid from dispensing device, hose leaks, or ruptured components will pierce skin. This
may look like just a cut, but it is a serious injury that can result in amputation. Get immediate surgical
treatment.
•Do not point dispensing device at anyone or at any part of the body.
•Do not put your hand over the fluid outlet.
•Do not stop or deflect leaks with your hand, body, glove, or rag.
•Follow the Pressure Relief Procedure when you stop dispensing and before cleaning, checking, or
servicing equipment.
•Tighten all fluid connections before operating the equipment.
•Check hoses and couplings daily. Replace worn or damaged parts immediately.

Warnings
4 308391P
EQUIPMENT MISUSE HAZARD
Misuse can cause death or serious injury.
•Do not operate the unit when fatigued or under the influence of drugs or alcohol.
•Do not exceed the maximum working pressure or temperature rating of the lowest rated system
component. See Technical Specifications in all equipment manuals.
•Use fluids and solvents that are compatible with equipment wetted parts. See Technical
Specifications in all equipment manuals. Read fluid and solvent manufacturer’s warnings. For
complete information about your material, request Safety Data Sheets (SDSs) from distributor or
retailer.
•Do not leave the work area while equipment is energized or under pressure.
•Turn off all equipment and follow the Pressure Relief Procedure when equipment is not in use.
•Check equipment daily. Repair or replace worn or damaged parts immediately with genuine
manufacturer’s replacement parts only.
•Do not alter or modify equipment. Alterations or modifications may void agency approvals and create
safety hazards.
•Make sure all equipment is rated and approved for the environment in which you are using it.
•Use equipment only for its intended purpose. Call your distributor for information.
•Route hoses and cables away from traffic areas, sharp edges, moving parts, and hot surfaces.
•Do not kink or over bend hoses or use hoses to pull equipment.
•Keep children and animals away from work area.
•Comply with all applicable safety regulations.
TOXIC FLUID OR FUMES HAZARD
Toxic fluids or fumes can cause serious injury or death if splashed in the eyes or on skin, inhaled, or
swallowed.
•Read Safety Data Sheets (SDSs) to know the specific hazards of the fluids you are using.
•Store hazardous fluid in approved containers, and dispose of it according to applicable guidelines.
BURN HAZARD
Equipment surfaces and fluid that is heated can become very hot during operation. To avoid severe
burns:
•Do not touch hot fluid or equipment.
MOVING PARTS HAZARD
Moving parts can pinch, cut or amputate fingers and other body parts.
•Keep clear of moving parts.
•Do not operate equipment with protective guards or covers removed.
•Equipment can start without warning. Before checking, moving, or servicing equipment, follow the
Pressure Relief Procedure and disconnect all power sources.
PERSONAL PROTECTIVE EQUIPMENT
Wear appropriate protective equipment when in the work area to help prevent serious injury, including
eye injury, hearing loss, inhalation of toxic fumes, and burns. This protective equipment includes but is
not limited to:
• Protective eyewear, and hearing protection.
• Respirators, protective clothing, and gloves as recommended by the fluid and solvent manufacturer
WARNING

Installation
308391P 5
Installation
Pump Accessories
Suction Tube Kit: A suction tube kit is available for
siphoning from 55 gallon containers.
Intake Tube: To install, apply PTFE tape to the female
threads at the top of the tube (Q). Screw the tube tightly
into the intake housing of the stubby pump.
Low-Level Cutoff Valve: To install, screw the low-level
cutoff valve into the bottom of the pump intake tube or
the suction tube. This valve closes the pump intake
when the fluid level is low, causing the pump to stall to
avoid running all day.
Pump Outlet Drain Valve: Install a drain valve (D) close
to the pump fluid outlet assist in relieving fluid pressure
in the pump, hose, and dispense valve when the pump
is shut off.
Thermal Relief Kit: Install a Thermal Relief Kit (T) at the
pump fluid outlet.
Grounding
Pump: Use a ground wire and clamp. Remove the
ground screw (Z) and insert through the eye of the ring
terminal at end of ground wire (Y). Fasten the ground
screw back onto the pump and tighten securely.
Connect the other end of the ground wire to a true earth
ground. (FIG. 1)
Hydraulic and fluid hoses: Use only electrically
conductive hoses.
Hydraulic power supply: Follow manufacturer’s
recommendations.
Any pails used when flushing: Use only metal,
grounded pails when flushing. Make firm
metal-to-metal contact between the metal part of the
dispense valve and the pail. Use the lowest possible
pressure.
Maximum Working Pressure of Accessories
To reduce the risk of serious injury including fluid
injection and splashing in the eyes or on the skin,
which may be caused by component ruptures, all
accessories added to the reciprocator power supply
side of the pump fluid outlet side must have at least a
1500 psi (10 MPa, 103 bar) maximum working
pressure.
The equipment must be grounded to reduce the risk
of static sparking. Static sparking can cause fumes
to ignite or explode. Grounding provides an escape
wire for the electric current.
FIG. 1
Y
Z

Installation
6 308391P
Key:
A Hydraulic Control (See manual 308395)
B Porous Plug (weep tube optional)
C Fluid Dispense Outlet
D Drain Valve (required)
E Hydraulic Return Line
F Hydraulic Outlet, 1 1/4 npt
G Return Line Shutoff Valve
H Hydraulic Inlet, 3/4 npt
J Hydraulic Supply Line Shutoff Valve
K Pressure Gauge
L Pressure Reducing Valve
M Flow Control Valve
N Hydraulic Supply Line (Use only Graco Hydraulic power
supply)
P Dispensed Material Supply Suction Hose Kit
R Ground Wire (required)
S Wall Mounting Bracket (See manual 308394)
T Thermal Relief Kit (required)
The installation shown in FIG. 2 is only a guide. For
assistance in designing a system to suit your needs.
Contact your Graco representative.
Mount the pump to suit the type of installation planned.
Hydraulic Power Supply
To reduce the risk of damaging the hydraulic power
supply, blow out all hydraulic lines with air, flush
thoroughly with solvent, and then blow out with air
again before connecting the lines to the motor.
Always plug the hydraulic inlets, outlets, and lines when
disconnecting them to avoid introducing dirt and other
contaminants to the system.
Carefully follow the manufacturers recommendations
on reservoir and filter cleaning, and periodic changes of
the hydraulic fluid.
FIG. 2: Typical Installation
HR
E
N
A
G
J
L
M
B
P
D
C
K
F
S
T
Note: Square housings shown

Installation
308391P 7
Hydraulic Components
Drain Line: Remove the plug (24) from the pump
adapter, and install a 1/8 inch diameter weep tube,
ending in a waste container. Monitor the weepage of
hydraulic fluid. If it seems excessive or increases
suddenly, the reciprocator or pump throat seals may
need to be changed. (FIG. 3)
Hydraulic Fluid Control: The hydraulic fluid control
provides pressure regulator, and pump isolation. (FIG.
2)
Pressure Regulation: The hydraulic fluid control reduces
the hydraulic oil pressure to the operating pressure
required for the application.
Flow Regulation: The hydraulic fluid control limits the
maximum amount of oil flow to the motor to keep the
hydraulic motor within the cycle rate limit. This prevents
pump runaway. The limit on the Power-Star is 66 cpm.
Pump Isolation: The hydraulic fluid control has ball
valves on the supply and return sides of the manifold.
The ball valves isolate the hydraulic fluid control and
pump for servicing without stopping the hydraulic
power supply.
Always turn off the hydraulic supply side valve (K)
first to avoid possible serious injury or component
damage. See the Typical Installation on page 6.
FIG. 3
24

Operation
8 308391P
Operation
Pressure Relief Procedure
Follow the Pressure Relief Procedure
whenever you see this symbol.
1. Close the supply line shutoff valve, and then the
return line shutoff valve.
2. Open the dispensing valve to relieve the pressure.
3. Place a container under the drain valve to catch any
drainage. Open the pump outlet drain valve.
4. Leave the drain valve open until you are ready to
dispense again.
If you suspect that the dispensing valve, extension, or
grease fitting coupler is clogged, or that the pressure
has not been fully relieved after following the steps
above, VERY SLOWLY loosen the coupler or hose end
coupling and relieve pressure gradually, then loosen
completely and clear the clog.
Before Starting the Pump
Recommended Hydraulic Oil
Use a Graco-approved Hydraulic Oil or a premium, ISO
grade 46 petroleum-based hydraulic oil containing rust
and oxidation inhibitors and anti-wear agents.
Before using any other type of oil in this motor contact
your Graco distributor. Unauthorized use of lesser
grade oil or substitutes may void the warranty.
1. Check the hydraulic fluid level in the hydraulic
power supply before each use, and add fluid as
necessary to fill the lines.
2. Flush the pump before using it for the first time to
remove the light oil that was left in after factory
testing to protect the pump from corrosion. Be sure
the solvent used is compatible with the fluid to be
pumped and the pump’s wetted parts. See
Technical Data, page 20. Flush until clean solvent
comes from the outlet hose.
To Start the Pump
1. Turn on the hydraulic power supply.
2. Open the return line shutoff valve (H) first, and
slowly open the hydraulic supply line shutoff valve
(K). (FIG. 2)
3. Adjust the hydraulic inlet pressure from 500 to 1500
psi (3.5 to 10.3 MPa, 35 to 103 bar) with the
regulator control adjustment (M) on the hydraulic
fluid control (A).
Increasing the inlet pressure increases the outlet
pressure. Decreasing the inlet pressure decreases
the outlet pressure. Always use the lowest pressure
possible to obtain the desired results. This reduces
pump wear.
To prevent the pump from running dry, use a low-level
cutoff valve.
This equipment stays pressurized until pressure is
manually relieved. To help prevent serious injury from
pressurized fluid, such as skin injection, splashing
fluid and moving parts, follow the Pressure Relief
Procedure when you stop spraying and before
cleaning, checking, or servicing the equipment.
NOTICE
Never allow a pump to run dry of the fluid being
pumped. A dry pump quickly speeds up and can
damage itself. If it speeds up, shut off the power
supply to the reciprocator immediately. Refill the
supply container and prime the pump to eliminate
air.

Operation
308391P 9
Shutdown and Care
At the end of the work shift or when the pump is
unattended, always relieve the pressure, see Pressure
Relief Procedure on page 8.
Emergency Stop Procedure
Close the supply line shutoff valve marked STOP.

Troubleshooting
10 308391P
Troubleshooting
1. Follow Pressure Relief Procedure, page 8, before
checking or repairing gun.
2. Check all possible problems and causes before
disassembling gun.
Problem Cause Solution
Pump will not run
Closed dispense valve Pump only runs with valve open.
Pressure too low Increase supply pressure using the
pressure adjusting valve.
Insufficient hydraulic fluid supply
Check hydraulic power supply.
Adjust to a maximum of 12 gpm
(45.4 lpm) flow
Clogged fluid outlet line, intake
valve, dispense valve, suction line Check; clear obstructions.
Motor stalled
Press reciprocator reset button (39).
Pump should start immediately. See
Parts Drawing on page 15.
Reciprocator damaged Repair. See pages 11 through 15.
Pump speeds up or runs erratically
Pump piston and/or intake valve
worn Check and repair. See Page 11
Empty supply container
Refill and reprime. Do not allow
pump to run dry. Monitor closely or
use a low-level cutoff valve.
Pump runs, but output low on up
and/or down strokes
Pump piston and/or intake valve
worn Check and repair. See Page 11.
Insufficient material fluid supply Refill fluid supply container.
Pressure too low Increase supply pressure using the
pressure adjustment on the control.
Clogged fluid outlet line, intake
valve, dispense valve, suction line Check; clear obstructions.
Excessive weepage from porous
plug (B) Worn throat seals Repair. See page 11
Hydraulic oil leaks from seal nuts in
the upper housing or cap (36, 43)
Seal nuts (19) are loose, worn, or
damaged
Tighten the seal nuts. If leaking
persists, change the seal nuts.
Pump runs slowly with dispense
valve closed Pump/dispense line leakage If system is OK, rebuild the pump. Use kits 220457 and 236862.

Repair
308391P 11
Repair
Refer to Parts Drawing on page 15 unless otherwise
specified.
• Spool valve Repair Kit 220457 is available to
replace the gaskets (29), spring retaining plugs (31),
springs (21), spool (38), trip rod (33) and piston stop
(37). The spool, plugs, and springs must be
replaced as a group.
• Clean all parts as you disassemble them, and
inspect for wear or damage. Replace parts as
necessary. Use Loctite® TL-242 thread sealant, or
equivalent, when thread sealant is specified.
• Pump Repair Kit 236862 is available to replace the
gasket (29), o-rings (11, 12, 105 and 108) seals (17),
packing (107), and piston rings (15).
Disassembly
Refer to Parts Drawing on page 15 unless otherwise
specified.
1. Relieve the pressure (page 8), and stop the pump at
the bottom of its stroke.
2. Disconnect the displacement pump hoses.
Disconnect the hydraulic hoses and plug all
hydraulic connections and lines to prevent
contamination.
3. Place the hydraulic motor horizontally in a bench
vise at the pump adapter (42) and bottom cylinder
cap (43).
4. Remove the displacement pump with a strap
wrench.
5. Remove the cap screws (25) and the mounting
plate (46).
6. Remove the hydraulic motor from the vise.
7. Place the piston (110) flats in the vise.
8. Loosen, but do not remove piston (44a) with a
wrench.
9. Remove the piston (110) flats from the vise.
10. Place the motor vertically in the vise at the pump
adapter (42) and the bottom cylinder cap (43).
11. Remove the piston (110), ball (103), and seal (107).
The socket screw (9), cap screws (22), and retainer
(44b) are fastened with Loctite® TL-242. Heat may be
used sparingly to soften the adhesive during
disassembly.
12. Remove one detent assembly retaining plug (31),
spring (21), gasket (29), ball guide (30), and ball (7).
If the ball or other parts stick in the upper housing
(36), use a magnet to extract the parts. Do not allow
the parts to fall into the motor. Repeat the
procedure for the other detent assembly.
13. Unscrew the top and bottom flare nuts on the
hydraulic tube (49), and remove the tube. Allow the
oil to drain from the motor into a pan.
14. Remove the socket screws (9), and remove the end
cap (40).
15. Remove the bolts (23), but do not remove the rods
(47).
To avoid serious injury, do not move this unit without
the use of lifting equipment. Keep the hoist attached
for steps 1 through 15.
NOTICE
Avoid getting dust or dirt in the motor during repair.
Cleanliness is essential when repairing a hydraulic
motor. Foreign particles like dust or dirt in the
hydraulic fluid can increase friction between moving
parts and increase component wear.
NOTICE
To prevent damage to the spool (38) and the upper
housing (36), remove the detent parts (31, 21, 29, 30,
and 7) before removing the end cap (40).

Repair
12 308391P
16. Remove the stop plug (39) from the upper housing
(36). Pull the upper housing about 3 inches off the
cylinder (35). Shim the housing with 3/4 in. flat
stock to keep an opening. The cylinder can stay in
the lower housing (43).
17. Hold the trip rod (33) steady with a trip rod pliers
(P/N 207579) on the rod, and remove the top hex
nut (16) from the trip rod.
18. Remove the upper housing (36). Remove the valve
spool (38) from the upper housing (36). Save the
spring collars (41), the springs (34), and the parts
remaining inside the upper housing.
19. Inspect the bore in the upper housing (36) and the
outside diameter of the valve spool (38) for wear.
Replace parts if damaged. Inspect the trip rod (33)
above the shoulder for damage. There must be no
reduction in diameter.
20. Pull the trip rod and piston (44a) from the lower
housing (43) and cylinder (35).
21. The seals (17) must be replaced if they are leaking.
Remove seals from adapter (42).
22. Perform steps 23 and 24 if parts inspected in step
19 are damaged.
23. Place the piston (44a) in a vise; tighten the vise on
the flats of the piston. Remove retaining ring (44c)
from piston. Use a spanner wrench to remove the
retainer (44b). Remove the trip rod (33) from the
piston (44a).
24. Remove the trip rod nut (10) and piston stop (37). If
the piston is replaced, remove the compression
springs (18), and compression rings (15) to use the
new piston.
Reassembly
Refer to FIG. 4 for the following instructions.
1. Place the pump adapter (42) in a vise. Grease the
new seal (17) from the repair kit. Install a seal in the
pump adapter (42) with the lip facings down. Install
the rod guide (45) and install the second seal with
the lip facing up in the pump adapter. Install the
bottom cylinder cap (43). Ensure all fluid ports are
facing the same direction.
2. Install the piston (44a) into the pump adapter (42)
and the bottom cylinder cap (43). Lubricate the
piston rings (15) and install the piston (44a) with the
openings on the rings opposed 180°.
3. Only perform steps 4 and 5 if steps 23 and 24 of
Disassembly were performed.
4. Install the compression spring (18) inside the
piston. Install the trip rod nut (10) and piston stop
(37) on the trip rod (33).
5. Install the trip rod (33) in the piston (44a). Apply
thread sealant to the retainer (44b). With the piston
flat in a vise, tighten the retainer until it is slightly
below the retaining ring groove. Install retaining ring
(44c). This is important to prevent the retainer from
backing out during operation and damaging the
motor.
Graco recommends replacing piston (44a), retainer
(44b), and retaining ring (44c) together in kit 26C143.
Retainer (44b) can be used on old pistons without
retaining groove, but must be threaded in completely.
6. Install the o-ring (12) on cylinder (35). Install the
cylinder over the piston and rings.
NOTICE
With the bolts removed, the assembly may separate
at the joints between the cylinder (35) and the upper
housing (36) and bottom cylinder cap (43). Hold
motor and housings securely when removing parts
to avoid premature separation of large parts and
possible damage to parts from falls.
44b
44a
44b
44a
44c
New Piston Old Piston

Repair
308391P 13
7. Install the upper housing (36). Install a 3/4 inch flat
stock shim between the upper housing and the
cylinder. Install the trip rod guide (41), the spring
(34), valve spool (38), and the remaining parts from
the inside of the upper housing. See Parts Drawing,
page 15,
8. Holding the trip rod (33) steady with a trip rod pliers
on the rod, and install the top hex nut (16) on the
trip rod.
9. Replace the o-ring (11) on the stop plug (39). Install
the stop plug in the upper housing (36).
10. Install tie rods (47) and bolts (23); hand tighten.
11. Install the two lock nuts (5) and washers (6).
12. Apply thread sealant to the socket screws (9).
Install the end cap (40) with the socket screws.
13. Install one detent assembly; retaining plug (31),
spring (21), gasket (29), ball guide (30), and ball (7).
Repeat for the other detent assembly.
14. Align the tie rods (47) and bolts (23) and torque to
70 to 80 ft-lbs (95 to 108 N.m). Install eyelet (26)
Attach hoist to the eyelet.
15. Screw the top and bottom flare nuts on the
hydraulic tube (49), and install the tube.
16. Place the motor horizontally in a vise at the pump
adapter (42) and the bottom cylinder cap (43).
17. Apply thread sealant to the threads of the piston
(110) and install the piston, ball (103), and the seal
(107) with the lips facing up.
18. Remove the hydraulic motor from the vise.
19. Place the piston (110) flats in a vise.
20. Tighten the piston (44a) with a wrench.
21. Remove the piston from the vise.
22. Place the pump horizontally in the vise.
23. Install the displacement pump with a strap wrench.
24. Remove the hydraulic motor from the bench vise.
25. Unplug all hydraulic connections and lines and
connect the hydraulic hoses. Connect the
displacement pump hoses.
26. Flush the displacement pump if possible. Relieve
the pressure (page 8)
Intake Valve
Refer to FIG. 5 for the following instructions.
1. Relieve the pressure, see page 8.
2. Unscrew the valve body (112). Remove the o-ring
(105), ball (104), and retainer (113).
3. Inspect the parts for wear or damage. If the ball is
nicked, replace it. Reassemble, using grease on the
male threads.
NOTICE
To avoid damaging the internal parts, install detent
parts (31, 21, 29, 30, and 7) after install the end cap
(40).
FIG. 4
26
5
22
33
18
16
41
50
12
15
12
17
42
47
25
Lips must face
up toward top of motor
Rings must be positioned
with joints opposed 180
38
31
30
7
41
Apply Loctite TL–242
thread sealant to threads
43
Torque to
70–80 ft–lb (95–108 N.m)
1
4
5
2
1
2
6
4
6
Concave surface faces ball
6
37
10
34
3436
9
7
7Torque to
120–130 ft–lb (163–176 N.m
)
17
3
Lips must face down to-
ward bottom of pump
3
4
5
29
21
46
44b
40
11
39
5
35
45
5
Note: Square housings
shown.

Repair
14 308391P
Displacement Pump
Refer to FIG. 5 for the following instructions.
Clean and inspect all parts for wear of damage as you
disassemble them. Replace parts as needed. For the
best results, always replace all the o-rings and
packings when you disassemble the pump.
1. Relieve the pressure, see page 8.
2. Remove the piston (110). Follow steps 1 through 11
of Disassembly (page 11).
3. Carefully inspect the smooth inner surface of the
cylinder (111) for scoring or irregular surfaces. Such
damage causes premature seal wear and leaking.
Replace the parts as needed.
4. Grease the new piston seal and install with the lips
facing up.
5. Reconnect the reciprocator and displacement
pump as described in steps 16 through 26 of
Reassembly, page 12.
FIG. 5
104
112
105
111
107
113
1
108

Parts
308391P 15
Parts
Model 236752, Series B - Square Housings
29
See the repair section for important
torque and lubrication notes
Rings must be positioned
with joints opposed 180
Torque to
70–80 ft–lb (95–108 N.m)
1
2
9
6
27
26
28
13
49
47
5
14
19
45
17
24
17
43
35
12
12
40
23
39
44b
37
10
15
15
18
44a
25
46
11
16
41
34
38
34
41
50
33
44c
7
30
21
31
19
22
36
3
2
2
42
1
1
Torque to
120–130 ft–lb (163–176 N.m)
3
4
5
4
5
Lips face up
Lips face down
56
54
ti20637b
Graco recommends replacing 44a,44b, and 44c
all together in Kit 26C143

Parts
16 308391P
Model 236752, Series B
▲Replacement safety labels, tags, and cards are
available at no cost. Also available in the following
languages:
German (Part No. 290396)
French (Part No. 290397)
Spanish (Part No. 290398)
† Parts included in Pump Repair Kit 236862 (purchase
separately).
◆ Graco recommends replacing 44a, 44b, and 44c all
together in Kit 26C143.
Items marked --- are not available separately.
Ref. Part Description Qty.
5 100127 NUT, mscr, hex, 5/8-11 unc-2B 2
6 LOCKWASHER, spring, 5/8” 4
7 101701 BALL, 1/4 inch dia 2
8 101754 PLUG, pipe, 3/8 npt(f) 1
9 CAPSCREW, soc hd, 5/16-18 x 1
inch
3
10 103450 NUT, hex, self locking, 5/16-18 1
11† O-RING, nitrile rubber 1
12† O-RING, nitrile rubber 2
13 104098 TEE, tube, for 3/4 in. (19 mm) tube 1
14 104099 ELBOW, 90°, for 3/4 in (19 mm)
tube
1
15† RING, piston, compression 2
16 104105 NUT, hex lock, 1/4-20 1
17† SEAL, v-block, polyurethane 2
18 104664 SPRING, compression 1
19 105429 NUT, seal, 3/4-14 npt 2
20 105430 NUT, seal, 1 in. npt 1
21 108522 SPRING, helical compression 2
22 108538 SCREW, soc flat hd, self locking,
1/4-20 x 1/2 in.
3
23 BOLT, hex hd 2
24 110064 PLUG, pipe, vented 1
25 112570 SCREW, cap, soc hd 4
26 112571 NUT, eye 2
27 112573 ADAPTER, pipe, female 1
28 112574 UNION, swivel 1
29† GASKET, plug 2
30 167210 GUIDE, ball 2
31 167431 PLUG, spring retaining 2
33 171407 ROD, trip 1
34 171411 SPRING, compression 2
35 171412 CYLINDER 1
36 172814 HOUSING, upper 1
37 181243 STOP, piston 1
38 181874 SPOOL, valve 1
39 183252 PLUG, stop 1
40 183290 CAP, end 1
41 183659 GUIDE, trip, shaft 2
42 189714 ADAPTER, pump 1
43 189715 CAP, cylinder, bottom 1
44 26C143 KIT, piston; includes items 44a,
44b, and 44c
1
44a◆--- PISTON 1
44b◆171398 RETAINER 1
44c◆114962 RING, retaining 1
45 189717 GUIDE, rod 1
46 189718 PLATE, mounting 1
47 189719 ROD, tie 2
48 189720 LABEL, identification 1
49 210108 TUBE 1
50 210292 BEARING and GUIDE 1
54 116343 SCREW, ground 1
56▲290331 LABEL, instruction, English 1
Ref. Part Description Qty.

Parts
308391P 17
Model 236752, Series C - Cylindrical Housings

Parts
18 308391P
Model 236752, Series C - Cylindrical Housings
▲Replacement safety labels, tags, and cards are
available at no cost. Also available in the following
languages:
German (Part No. 290396)
French (Part No. 290397)
Spanish (Part No. 290398)
†Parts included in Pump Repair Kit 236862 (purchase
separately).
◆ Graco recommends replacing 44a, 44b, and 44c all
together in Kit 26C143.
Items marked --- are not available separately.
Ref. Part Description Qty.
5 100127 NUT, mscr, hex, 5/8-11 unc-2B 2
6 LOCKWASHER, spring, 5/8” 4
7 101701 BALL, 1/4 inch dia 2
8 101754 PLUG, pipe, 3/8 npt(f) 1
9 CAPSCREW, soc hd, 5/16-18 x 1
inch
3
10 103450 NUT, hex, self locking, 5/16-18 1
11† O-RING, nitrile rubber 1
12† O-RING, nitrile rubber 2
13 104098 TEE, tube, for 3/4 in. (19 mm) tube 1
14 104099 ELBOW, 90°, for 3/4 in (19 mm)
tube
1
15† RING, piston, compression 2
16 104105 NUT, hex lock, 1/4-20 1
17† SEAL, v-block, polyurethane 2
18 104664 SPRING, compression 1
19 105429 NUT, seal, 3/4-14 npt 2
20 105430 NUT, seal, 1 in. npt 1
21 108522 SPRING, helical compression 2
22 108538 SCREW, soc flat hd, self locking,
1/4-20 x 1/2 in.
3
23 BOLT, hex hd 2
24 110064 PLUG, pipe, vented 1
25 112570 SCREW, cap, soc hd 4
26 112571 NUT, eye 2
27 112573 ADAPTER, pipe, female 1
28 112574 UNION, swivel 1
29† GASKET, plug 2
30 167210 GUIDE, ball 2
31 167431 PLUG, spring retaining 2
33 171407 ROD, trip 1
34 171411 SPRING, compression 2
35 171412 CYLINDER 1
36 19D965 HOUSING, upper 1
37 181243 STOP, piston 1
38 181874 SPOOL, valve 1
39 183252 PLUG, stop 1
40 183290 CAP, end 1
41 183659 GUIDE, trip, shaft 2
42 19D966 ADAPTER, pump 1
43 19D967 CAP, cylinder, bottom 1
44 26C143 KIT, piston; includes items 44a,
44b, and 44c
1
44a◆--- PISTON 1
44b◆171398 RETAINER 1
44c◆114962 RING, retaining 1
45 189717 GUIDE, rod 1
46 189718 PLATE, mounting 1
47 189719 ROD, tie 2
48 189720 LABEL, identification 1
49 210108 TUBE 1
50 210292 BEARING and GUIDE 1
54 116343 SCREW, ground 1
56▲290331 LABEL, instruction, English 1
Ref. Part Description Qty.

Parts
308391P 19
Model 236754, Series B - Cylindrical Housings
† Parts included in Pump Repair Kit 236862 (purchase
separately).
104
110
113
108
112
114
111
107
105
103
101
Ref. Part Description Qty.
101 236752 RECIPROCATOR, hydra,
Power-Star
1
103 101178 BALL, metallic 1
104 108001 BALL, metallic, sst 1
105† PACKING, o-ring 1
107† SEAL, block vee 1
108† PACKING, o-ring 1
110 189707 PISTON, fluid 1
111 189708 CYLINDER, pump 1
112 189709 VALVE, housing 1
113 189710 RETAINER, ball 1
114 189711 WASHER, piston 1

Technical Data
20 308391P
Technical Data
Dimensions
Power-Star™
US Metric
Fluid Ratio 1:1
Maximum Cycle Rate 60 cpm
Maximum Output Flow 12.0 gpm 45.4 lpm
Maximum Output Pressure 1500 psi 10.3 MPa, 103 bar
Maximum Input Flow 12.0 gpm 45.4 lpm
Maximum Hydraulic Fluid Input Pressure 1500 psi 10.3 MPa, 103 bar
Maximum Input Fluid Temperature 130°F 55°C
Pressure Reducing Adjustment Range 300-1500 psi 2.07 - 10.3 MPa, 20.7 - 103 bar
Weight (Model 236752, Series B) 100lb 45.4 kg
Weight (Model 236752, Series C and 236754,
Series B, Cylindrical housings)
120lb 54.4kg
Rod Seals Nitrile
Piston Seals Polyurethane
Displacement Pump Wetted Parts Iron, Steel, SST Nitrile, Polyurethane
Sound Pressure 78 dB(A)*
* Sound pressure reading taken with pump operating at 60 cycles per minute. Sound pressure measured per
CAGI-PNEUROP, 1971
Loctite® is a registered trademark of the Loctite Corporation.
30 in.
(762 mm)
7.0 in.
(177.8 mm)
8.0 in.
(203.2 mm)
.406 in. ( 10.31 mm) diameter (4);
for 3/8 in. screw
4.0 in.
(101.6 mm)