Graco Check-Mate 450 Operation manual

308–017
Rev. L
Supersedes E
and PCN K
Model 222–768 Shown
0423
INSTRUCTIONS-PARTS LIST
INSTRUCTIONS
This manual contains important
warnings and information.
READ AND KEEP FOR REFERENCE.
CARBON STEEL
Check-Mate 450 Pumps
WITH PRIMING PIST ON, AND
SEVERE-DUTY ROD AND CYLINDER
For Pump Model Nos., Ratios, and Working Pressures,
refer to page 2.
U.S. Patent Nos. 5,147,188 and 5,154,532.
Table of Contents
List of Models 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Symbols 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Warnings 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operation 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Service
Troubleshooting 12
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Required Tools 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disconnecting the Displacement Pump 14. . . . . . . .
Reconnecting the Displacement Pump 15. . . . . . . .
Displacement Pump Service 16. . . . . . . . . . . . . . . . .
Parts 22 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Technical Data and Performance Charts 32. . . . . . . . .
Dimensions 38 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mounting Hole Layout 39. . . . . . . . . . . . . . . . . . . . . . . . . .
Warranty 40 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Toll-Free Graco Phone Numbers 40. . . . . . . . . . . . . . . .
GRACO INC. P.O. BOX 1441 MINNEAPOLIS, MN 55440–1441
COPYRIGHT 1990, GRACO INC.
Graco Inc. is registered to I.S. EN ISO 9001

2 308–017
List of Models
Maximum Air
W orking Pressure
Maximum Fluid
Working
Pressure
Model No. Description bar psi bar psi
222–770 10:1 ratio Monark  Pump, Series A
(UHMWPE/  Packed)
12.5 180 125 1800
235–626 10:1 ratio Monark  Pump, Series A
( Packed)
12.5 180 125 1800
222–768 20:1 ratio President  Pump, Series A
(UHMWPE/  Packed)
12.5 180 250 3600
237–207 20:1 ratio stubby President  Pump,
Series A (UHMWPE/  Packed)
12.5 180 250 3600
222–769 34:1 ratio Senator  Pump, Series A
(UHMWPE/  Packed)
8.3 120 281 4080
224–660 34:1 ratio Quiet Senator  Pump,
Series A (UHMWPE/  Packed)
8.3 120 281 4080
237–492 34:1 ratio stubby Senator  Pump,
Series A (UHMWPE/  Packed)
8.3 120 281 4080
237–780 34:1 ratio stubby Quiet Senator 
Pump, Series A
(UHMWPE/  Packed)
8.3 120 281 4080
222–778 55:1 ratio Bulldog  Pump, Series A
(UHMWPE/  Packed)
6.3 90 347 4950
222–813 55:1 ratio Quiet Bulldog  Pump,
Series A (UHMWPE/  Packed)
6.3 90 347 4950
237–208 55:1 ratio stubby Bulldog  Pump,
Series A (UHMWPE/  Packed)
6.3 90 347 4950
237–779 55:1 ratio stubby Quiet Bulldog 
Pump, Series A
(UHMWPE/  Packed)
6.3 90 347 4950
PTFE
PTFE
PTFE
PTFE
PTFE
PTFE
PTFE
PTFE
PTFE
PTFE
PTFE
PTFE

308–017 3
Symbols
Warning Symbol
WARNING
This symbol alerts you to the possibility of serious
injury or death if you do not follow the instructions.
Caution Symbol
CAUTION
This symbol alerts you to the possibility of damage to
or destruction of equipment if you do not follow the
instructions.
WARNING
INSTRUCTIONS
EQUIPMENT MISUSE HAZARD
Equipment misuse can cause the equipment to rupture or malfunction and result in serious injury .
D
This equipment is for professional use only .
D
Read all instruction manuals, tags, and labels before operating the equipment.
D Use the equipment only for its intended purpose. If you are not sure, call your Graco distributor .
D
Do not alter or modify this equipment.
D Check equipment daily . Repair or replace worn or damaged parts immediately .
D Do not exceed the maximum working pressure stated on the equipment or in the T echnical Data
for your equipment. Do not exceed the maximum working pressure of the lowest rated component
in your system.
D Use fluids and solvents which are compatible with the equipment wetted parts. Refer to the Tech-
nical Data section of all equipment manuals. Read the fluid and solvent manufacturer ’ s warnings.
D Do not use hoses to pull equipment.
D Route hoses away from traffic areas, sharp edges, moving parts, and hot surfaces. Do not expose
Graco hoses to temperatures above 82 _ C (180 _ F) or below –40 _ C (–40 _F).
DW
ear hearing protection when operating this equipment.
D Comply with all applicable local, state, and national fire, electrical, and safety regulations.

4 308–017
WARNING
INJECTION HAZARD
Spray from the spray gun/dispense valve, leaks or ruptured components can inject fluid into your body
and cause extremely serious injury , including the need for amputation. Fluid splashed in the eyes or on
the skin can also cause serious injury .

Fluid injected into the skin might look like just a cut, but it is a serious injury . Get immediate medi -
cal attention.

Do not point the gun/valve at anyone or at any part of the body .
 Do not put your hand or fingers over the spray tip/nozzle.
 Do not stop or deflect leaks with your hand, body , glove or rag.
 Do not “blow back” fluid; this is not an air spray system.
 Always have the tip guard and the trigger guard on the gun when spraying.
 Check the gun dif fuser operation weekly . Refer to the gun manual.
 Be sure the gun/valve trigger safety operates before spraying.
 Lock the gun/valve trigger safety when you stop spraying.
 Follow the Pressure Relief Procedure on page 9 if the spray tip/nozzle clogs and before clean -
ing, checking or servicing the equipment.
T ighten all fluid connections before operating the equipment.
 Check the hoses, tubes, and couplings daily . Replace worn or damaged parts immediately . Do not
repair high pressure couplings; you must replace the entire hose.
 Fluid hoses must have spring guards on both ends, to help protect them from rupture caused by
kinks or bends near the couplings.
MOVING P ARTS HAZARD
Moving parts, such as the priming piston, can pinch or amputate your fingers.
 Keep clear of all moving parts when starting or operating the pump.
 Keep hands and fingers away from the priming piston during operation and whenever the pump is
charged with air
.

Before servicing the equipment, follow the Pressure Relief Procedure on page 9 to prevent the
equipment from starting unexpectedly.

308–017 5
WARNING
FIRE AND EXPLOSION HAZARD
Improper grounding, poor ventilation, open flames or sparks can cause a hazardous condition and re -
sult in a fire or explosion and serious injury .
 Ground the equipment and the object being sprayed. Refer to Grounding on page 8.
 If there is any static sparking or you feel an electric shock while using this equipment, stop spray-
ing/dispensing immediately . Do not use the equipment until you identify and correct the problem.
 Provide fresh air ventilation to avoid the buildup of flammable fumes from solvents or the fluid be -
ing sprayed/dispensed.
 Keep the spray/dispense area free of debris, including solvent, rags, and gasoline.
 Electrically disconnect all equipment in the spray/dispense area.
 Extinguish all open flames or pilot lights in the spray/dispense area.
 Do not smoke in the spray/dispense area.
 Do not turn on or of f any light switch in the spray/dispense area while operating or if fumes are
present.
 Do not operate a gasoline engine in the spray/dispense area.
TOXIC FLUID HAZARD
Hazardous fluid or toxic fumes can cause serious injury or death if splashed in the eyes or on the skin,
inhaled, or swallowed.
 Know the specific hazards of the fluid you are using.
 Store hazardous fluid in an approved container . Dispose of hazardous fluid according to all local,
state and national guidelines.
 Always wear protective eyewear , gloves, clothing and respirator as recommended by the fluid and
solvent manufacturer .

6 308–017
Installation
General Information
NOTE: Reference numbers and letters in parentheses
in the text refer to the callouts in the figures and the
parts drawings.
NOTE: Always use Genuine Graco Parts and
Accessories, available from your Graco distributor .
Refer to the Product Data Sheet, Form No. 305–546. If
you supply your own accessories, be sure they are
adequately sized and pressure-rated to meet the
system’ s requirements.
Fig. 1 is only a guide for selecting and installing sys -
tem components and accessories. Contact your Graco
distributor for assistance in designing a system to suit
your particular needs.
System Accessories
WARNING
A red-handled main air bleed valve (V), pump air
bleed valve (G), and fluid drain valve (L) are re -
quired. These accessories help reduce the risk of
serious injury , including fluid injection and splashing
of fluid in the eyes or on the skin, and injury from
moving parts if you are adjusting or repairing the
pump.
The red-handled main air bleed valve (V) shuts of f
and relieves the air to the pump and ram. Order
Part No. 1 13–269 for Monark and President
Pumps, or 113–218 for Senator and Bulldog
Pumps. The ram will hold pressure if the ram
director valve (U) is in the horizontal (neutral)
position. T o relieve air pressure in the ram, close
the red-handled bleed valve (V) and move the
director valve (U) to DOWN. The ram will slowly
drop.
The pump air bleed valve (G) relieves air trapped
between it and the pump after the air is shut of f.
T
rapped air can cause the pump to cycle unexpect -
edly
. Locate the valve close to the pump.
The fluid drain valve (L) assists in relieving fluid
pressure in the displacement pump, hose, and gun.
T riggering the gun to relieve pressure may not be
suf ficient. Order Part No. 210–658 (3/8 npt).
Air Line
Install the following accessories as shown in Fig. 1,
using adapters as necessary:
 A red-handled main air bleed valve (V) is re -
quired in your system to shut of f the air supply to
the pump and ram (see the WARNING at left).
When closed, the valve will bleed of f all air in the
ram and pump, and the ram will slowly drop. Be
sure the valve is easily accessible from the pump,
and is located upstream from the air manifold (D).
 The pump air bleed valve (G) is required in your
system to relieve air trapped between it and the air
motor when the valve is closed (see the WARNING
at left). Be sure the valve is easily accessible from
the pump, and is located downstream from the air
regulator (H).
The
pump air regulator (H) controls pump speed
and outlet pressure by adjusting the air pressure to
the pump. Locate the regulator close to the pump,
but
upstream from the pump air bleed valve (G).
An air line lubricator (F) provides automatic air
motor lubrication.
A pump runaway valve (E ) senses when the
pump is running too fast and automatically shuts of f
the air to the motor . A pump which runs too fast can
be seriously damaged.
 An air manifold (D) has a swivel air inlet. It has
ports for connecting lines to air accessories, such
as the
ram air regulator (T), which controls the air
pressure to the ram.
 The air pressure relief valve (Q) limits the air
pressure to the ram to 10 bar (150 psi).
 The ram director valve (U) controls the raising
and lowering of the ram.
An air line filter (J) removes harmful dirt and mois -
ture from the compressed air supply . Also, install a
drain valve (W) at the bottom of each air line drop,
to drain off moisture.
 A bleed-type air valve (K) isolates the air line ac -
cessories for servicing. Locate upstream from all
other air line accessories.

308–017 7
Installation
Fluid Line Accessories
Install the following accessories in the positions shown
in Fig. 1, using adapters as necessary:
 Install a fluid drain valve (L) in a tee near the
pump fluid outlet. The drain valve is required in your
system to relieve fluid pressure in the displacement
pump, hose and gun/valve (see the WARNING on
page 6). Install with the drain valve pointing down,
but so the handle points up when the valve is open.
A fluid regulator (M) controls fluid pressure to the
gun/valve, and dampens pressure surges.
A gun or dispense valve (N) dispenses the fluid.
The gun shown in Fig. 1 is a high pressure dispens -
ing gun for highly viscous fluids.
 A gun/valve swivel (P) allows freer gun/valve
movement.
Air and Fluid Hoses
Be sure all air hoses (S) and fluid hoses (R) are prop -
erly sized and pressure-rated for your system. Use
only electrically conductive hoses. Fluid hoses must
have spring guards on both ends.

Fig. 1
KEY
APump
B19
Liter (5 Gallon) Air-Powered Ram
C Wiper Plate
D Air Manifold
E Pump Runaway V alve (location shown)
F Air Line Lubricator (location shown)
G Pump Bleed-T ype Air V alve
(required, for pump)
H Pump Air Regulator
J Air Line Filter
KBleed-T ype Air V alve (for accessories)
L Fluid Drain V alve (required)
M Fluid Pressure Regulator
N Airless Spray Gun or Dispensing V alve
PGun/V
alve Swivel
Q Ram Air Pressure Relief V alve
R
Electrically Conductive Fluid Supply Hose
S Electrically Conductive Air Supply Hose
T Ram Air Regulator
U Ram Director V alve
V
Red-Handled Main Air Bleed V alve
W
Air LIne Drain V alve
Y
Ground Wire (required, see page 8 for
installation instructions)
A
B
D
E
F
G
JK
Y
R
T
L
N
P
S
M
C
W
H
S
V
QU

8 308–017
Installation
Grounding
WARNING
FIRE AND EXPLOSION HAZARD
Before operating the pump, ground the
system as explained below . Also read
the section FIRE OR EXPLOSION
HAZARD on page 5.
1. Pump: use a ground wire and clamp. See Fig. 2.
Loosen the grounding lug locknut (W) and washer
(X). Insert one end of a 1.5 mm  (12 ga) minimum
ground wire (Y) into the slot in lug (Z) and tighten
the locknut securely . Connect the other end of the
wire to a true earth ground. Order Part No.
237–569 Ground Wire and Clamp.
Fig. 2
W
X
Y
Z
0864
2. Air and fluid hoses: use only electrically conductive
hoses.
3.
Air compressor: follow manufacturer ’ s recommen -
dations.
4.
Spray gun/dispense valve: ground through connec -
tion to a properly grounded fluid hose and pump.
5. Fluid supply container: follow your local code.
6. Object being sprayed: follow your local code.
7. All solvent pails used when flushing: follow your
local code. Use only metal pails, which are con -
ductive, placed on a grounded surface. Do not
place the pail on a nonconductive surface, such as
paper or cardboard, which interrupts the grounding
continuity.
8.
T o maintain grounding continuity when flushing or
relieving pressure , always hold a metal part of the
gun/valve firmly to the side of a grounded metal
pail, then trigger the gun/valve.
Mounting Accessories
Mount the pump (A) to suit the type of installation
planned. Pump dimensions and the mounting hole
layout are shown on pages 38 and 39.
If you are mounting the pump on a ram (B), refer to the
manual supplied with the ram for installation and oper -
ation instructions. The ram shown in Fig. 1 is a 19 liter
(5 gal.) pail ram, used with a wiper plate (C). The ram
shown includes an air regulator (T). It also requires an
air supply hose (S) and an air manifold (D), which di -
vides the main air supply into separate lines for the
pump and the ram.
By using Pump Mounting Kit 222–776, you can also
mount the pump on Floor Stand 222–780, 200 liter (55
gal.) Ram 207–279, or Inductor 222–635.

308–017 9
Operation
Pressure Relief Procedure
WARNING
INJECTION HAZARD
The system pressure must be manually
relieved to prevent the system from
starting or dispensing accidentally . Fluid
under high pressure can be injected through the
skin and cause serious injury . T o reduce the risk of
an injury from injection, splashing fluid, or moving
parts, follow the Pressure Relief Procedure
whenever you:
 are instructed to relieve the pressure,
 stop spraying/dispensing,
 check or service any of the system equipment,
 or install or clean the spray tip/nozzle.
1. Lock the gun/valve trigger safety .
2. Close the pump’ s bleed-type air valve (G, required
in your system).
3. Shut of f the red-handled main air bleed valve (V ,
required in your system). If the pump is mounted
on a ram, set the ram director valve (U) to DOWN.
The ram will slowly drop.
4. Unlock the gun/valve trigger safety .
5. Hold a metal part of the gun/valve firmly to the side
of a grounded metal pail, and trigger the gun/valve
to relieve pressure.
6. Lock the gun/valve trigger safety .
7. Open the drain valve (required in your system),
having a container ready to catch the drainage.
8. Leave the drain valve open until you are ready to
spray/dispense again.
If you suspect that the spray tip/nozzle or hose is com -
pletely clogged, or that pressure has not been fully re -
lieved after following the steps above, very slowly
loosen the tip guard retaining nut or hose end coupling
and relieve pressure gradually , then loosen completely .
Now clear the tip/nozzle or hose.
Packing Nut/Wet-Cup
Before starting, fill the packing nut (2) 1/3 full with
Graco Throat Seal Liquid (TSL) or compatible solvent.
See Fig. 3.
WARNING
T o reduce the risk of serious injury whenever you
are instructed to relieve pressure, always follow the
Pressure Relief Procedure at left.
The packing nut is torqued at the factory and is ready
for operation. If it becomes loose and there is leaking
from the throat packings, relieve pressure, then torque
the nut to 45–53 N.m (33–39 ft-lb) using the supplied
wrench (1 10). Do this whenever necessary . Do not
overtighten the packing nut.
25
35
2
BB
0423
Fig. 3
1Bleed
hole must face down.
110
1
2T
orque to 45–53 N.m (33–39 ft-lb).
2
AA
23

10 308–017
Operation
Flush the Pump Before First Use
The pump is tested with lightweight oil, which is left in
to protect the pump parts. If the fluid you are using
may be contaminated by the oil, flush it out with a
compatible solvent. See Flushing on page 1 1.
Starting and Adjusting the Pump
WARNING
MOVING P ARTS HAZARD
See Fig. 3. The priming piston (25) and
the air motor piston (located behind the
air motor plates, AA) move during opera -
tion.
Keep hands and fingers away from the priming pis -
ton (25) during operation and whenever the pump
is charged with air . The priming piston extends be -
yond the intake cylinder (23) to pull material into
the pump and can amputate a hand or finger
caught between it and the intake cylinder . Follow
the Pressure Relief Procedure on page 9, be -
fore checking, clearing, or cleaning the priming pis -
ton.
Never operate the pump with the air motor plates
(AA) removed.
1. Do not install the spray tip yet.
2. Supply fluid to the pump, per the requirements of
your system.
3. See Fig. 1. Close the pump air regulator (H).
4. Open the red-handled main air bleed valve (V) and
the pump’
s bleed-type air valve (G).
5. Hold a metal part of the gun/valve (N) firmly to the
side of a grounded metal pail and hold the trigger
open.
6.
Slowly open the air regulator (H) until the pump
starts.
7.
Cycle the pump slowly until all air is pushed out
and the pump and hoses are fully primed.
8. Release the gun/valve trigger and lock the trigger
safety . The pump should stall against pressure.
WARNING
INJECTION HAZARD
T o reduce the risk of fluid injection, do not use
your hand or fingers to cover the bleed hole (BB)
on the underside of the bleeder valve (35) when
priming the pump.
9. If the pump fails to prime properly , open the
bleeder valve (35) slightly . Use the bleed hole (BB)
on the underside of the valve as a priming valve
until the fluid appears at the hole. See Fig. 3.
Close the bleeder valve.
NOTE: When changing fluid containers with the hose
and gun/valve already primed, open the bleeder valve
(35) to help prime the pump and vent air before it en -
ters the hose. Close the bleeder valve when all air is
eliminated.
CAUTION
Do not allow the pump to run dry . It will quickly accel -
erate to a high speed, causing damage. If your pump
is running too fast, stop it immediately and check the
fluid supply . If the container is empty and air has
been pumped into the lines, refill the container and
prime the pump and the lines, or flush and leave it
filled with a compatible solvent. Eliminate all air from
the fluid system.

308–017 11
Operation
Starting and Adjusting the Pump
(continued)
10. With the pump and lines primed, and with ade -
quate air pressure and volume supplied, the pump
will start and stop as you open and close the gun/
valve. In a circulating system, the pump will speed
up or slow down on demand, until the air supply is
shut of
f.
WARNING
T o reduce the risk of serious injury whenever you
are instructed to relieve pressure, always follow the
Pressure Relief Procedure on page 9.
11. Relieve the pressure. Install the spray tip in the
gun.
WARNING
COMPONENT RUPTURE HAZARD
T o reduce the risk of overpressurizing
your system, which could cause compo -
nent rupture and serious injury , never
exceed the Maximum Incoming Air Pressure to the
pump (see the T echnical Data on pages 32–37).
12. Use the air regulator (H) to control the pump speed
and the fluid pressure. Always use the lowest air
pressure necessary to get the desired results.
Higher pressures cause premature tip/nozzle and
pump wear .
Shutdown and Care of the Pump
WARNING
To reduce the risk of serious injury whenever you
are instructed to relieve pressure, always follow the
Pressure Relief Procedure on page 9.
For overnight shutdown, stop the pump at the bottom
of the stroke to prevent fluid from drying on the ex
-
posed displacement rod and damaging the throat
packings. Relieve the pressure.
Always flush the pump before the fluid dries on the
displacement rod. Refer to Flushing at right.
Flushing
WARNING
FIRE AND EXPLOSION HAZARD
Before operating the pump, read the
section FIRE OR EXPLOSION HAZ -
ARD
on page 5. Be sure the entire
system and flushing pails are properly
grounded. Refer to Grounding on page
8.
Flush with a fluid that is compatible with the fluid you
are pumping and with the wetted parts in your system.
Check with your fluid manufacturer or supplier for rec -
ommended flushing fluids and flushing frequency . Al -
ways flush the pump before fluid dries on the displace -
ment rod.
CAUTION
Never leave water or water-base fluid in the pump
overnight. If you are pumping water-base fluid, flush
with water first, then with a rust inhibitor such as min -
eral spirits. Relieve the pressure, but leave the rust
inhibitor in the pump to protect the parts from corro -
sion.
WARNING
T o reduce the risk of serious injury whenever you
are instructed to relieve pressure, always follow the
Pressure Relief Procedure on page 9.
1. Relieve the pressure.
2. Remove the spray tip/nozzle from the gun/valve.
3. Hold a metal part of the gun/valve firmly to the side
of a grounded metal pail.
4. Start the pump. Always use the lowest possible
fluid pressure when flushing.
5. T rigger the gun/valve.
6. Flush the system until clear solvent flows from the
gun/valve.
7.
Relieve the pressure.

12 308–017
Troubleshooting
WARNING
T o reduce the risk of serious injury whenever you
are instructed to relieve pressure, always follow the
Pressure Relief Procedure on page 9.
1. Relieve the pressure.
2. Check all possible problems and causes before
disassembling the pump.
PROBLEM CAUSE SOLUTION
Pump fails to operate. Restricted line or inadequate air supply;
closed or clogged valves.
Clear; increase the air supply .
Check that all valves are open.
Obstructed fluid hose or gun/valve;
fluid hose ID is too small.
Open, clear*; use a hose with a larger ID.
Fluid dried on the displacement rod. Clean; always stop the pump at the bottom of its
stroke;
keep the wet-cup 1/3 filled with a compat -
ible
solvent.
Dirty , worn, or damaged motor parts. Clean or repair; see the separate motor manual.
Pump operates, but
output is low on both
strokes.
Restricted line or inadequate air supply;
closed or clogged valves.
Clear; increase the air supply .
Check that all valves are open.
Obstructed fluid hose or gun/valve;
fluid hose ID is too small.
Open, clear*; use a hose with a larger ID.
Bleeder valve is open. Close the valve.
Air is leaking into the supply container . Check the ram plate seal.
Fluid is too heavy for pump priming. Use the bleeder valve (see page 10); use a ram.
Held open or worn intake valve or seals. Clear the valve; replace the seals.
Worn packings in the displacement
pump.
Replace the packings.
Pump operates, but
output is low on down-
stroke.
Fluid too heavy for pump priming. Use the bleeder valve (see page 10); use a ram.
Held open or worn intake valve or seals. Clear the valve; replace the seals.
Pump operates, but
output is low on up-
stroke.
Held open or worn piston valve or seals. Clear the valve; replace the seals.
THE TROUBLESHOOTING CHAR T IS CONTINUED ON P AGE 13.
*T o determine if the fluid hose or gun is obstructed, follow the Pressure Relief Procedure on page 9. Discon -
nect the fluid hose and place a container at the pump fluid outlet to catch any fluid. T urn on the air just enough
to start the pump. If the pump starts when the air is turned on, the obstruction is in the fluid hose or gun.

308–017 13
Troubleshooting
PROBLEM CAUSE SOLUTION
Erratic or accelerated
pump
speed.
Exhausted fluid supply . Refill and prime.
Fluid is too heavy for pump priming. Use the bleeder valve (see page 10); use a ram.
Held open or worn piston valve or seals. Clear the valve; replace the seals.
Held open or worn priming piston. Clear; service.
Worn packings in the displacement
pump.
Replace the packings.

14 308–017
Service
Required Tools
Torque wrench
 Bench vise, with soft jaws
 Rubber mallet
Hammer

O-ring pick
 13 mm (1/2 in.) dia. brass rod
 Set of socket wrenches
 Set of adjustable wrenches
 Pipe wrench
 Packing nut wrench (1 10, supplied)
 Thread lubricant
 Thread sealant
Disconnecting the Displacement Pump
1. Flush the pump, if possible. Stop the pump at the
bottom of its stroke.
WARNING
T o reduce the risk of serious injury whenever you
are instructed to relieve pressure, always follow the
Pressure Relief Procedure on page 9.
2. Relieve the pressure.
3. Disconnect the air hose. Hold the fluid outlet fitting
(8) with a wrench to keep it from being loosened
while you disconnect the fluid hose.
4. Remove the pump from its mounting. Disconnect
the displacement pump (107) from the motor (101)
as follows. Be sure to note the relative position of
the pump’ s fluid outlet (8) to the motor air inlet
(CC).
5.
Using an adjustable wrench (or a hammer and
rod), unscrew the coupling nut (104) from the con -
necting rod (103). Do not lose or drop the coupling
collars (105). See Fig. 4.
6. Hold the tie rod flats with a wrench to keep the
rods from turning. Use the wrench (1 10) provided
with the pump to unscrew the nuts (106) from the
tie rods (102). Carefully remove the displacement
pump (107) from the motor (101).
7.
Refer to page 16 for displacement pump service.
T o service the air motor , refer to the separate mo -
tor manual, supplied.

308–017 15
Service
Reconnecting the Displacement Pump
1. Make sure the coupling nut (104) and the coupling
collars (105) are in place on the displacement rod
(1). See Fig. 4.
2. Orient the pump’s fluid outlet (8) to the air inlet
(CC) as was noted in step 4 under Disconnecting
the Displacement Pump. Position the displace -
ment pump (107) on the tie rods (102).
NOTE: Refer to Fig. 4 and the T orque Chart for proper
torque values for your pump.
3. If you removed the tie rods (102) from the air mo -
tor (101), reinstall them using an 11 mm wrench.
T orque as specified.
4. Screw the nuts (106) onto the tie rods (102) and
torque as specified.
5. Screw the coupling nut (104) onto the connecting
rod (103) loosely . Hold the connecting rod flats
with a wrench to keep it from turning. Using an
adjustable wrench, torque the coupling nut.
6. Using a torque wrench in the square hole of the
supplied wrench (1
10), torque the packing nut (2).
7. Mount the pump and reconnect all hoses. Recon -
nect the ground wire if it was disconnected. Fill the
wet-cup (2) 1/3 full of Graco Throat Seal Liquid or
compatible solvent.
8. T urn on the air supply . Run the pump slowly to en -
sure proper operation.
WARNING
T o reduce the risk of serious injury whenever you
are instructed to relieve pressure, always follow the
Pressure Relief Procedure on page 9.
9. Before returning the pump to production, relieve
the pressure and retorque the packing nut (2).
PUMP T ORQUE CHART (Refer to Fig. 4)
Pump
Model
Tie Rod
(102)
Tie Rod
Nut
(106)
Coupling
Nut (104)
Packing
Nut (2)
222–768
237–207 4 1 3 2
222–769,
222–770,
222–778,
222–813,
224–660,
235–626
5 1 3 2
237–208,
237–492,
237–779,
237–780
7 7 6 2
Fig. 4
1
3
4
2
101
111
102
103
104
105
107
106
Torque to 20–25 N.m
(15–18 ft-lb).
T orque to 50–61 N.m
(37–45 ft-lb).
Model 222–768
President Pump
Shown
8
2
0424
110
Torque to 45–53 N.m
(33–39 ft-lb).
T orque to 27–34 N.m
(20–25 ft-lb).
4
3
2
1
1
CC
5
6
7
T
orque to 36–45 N.m
(27–33 ft-lb).
T orque to 195–210 N.m
(145–155 ft-lb).
T orque to 81–89 N.m
(60–66 ft-lb).
or
or
or 7
6
,5,
7

16 308–017
Service
Displacement Pump Service
Disassembly
When
disassembling the pump, lay out all removed
parts in sequence, to ease reassembly
.
NOTE: Repair Kit 222–773 is available for Displace -
ment Pumps 222–790, 237–206, and 237–450. The kit
includes piston and intake seals and cylinder o-rings.
For the best results, use all the new parts in the kit. Kit
parts are marked with one asterisk, for example (1 1*).
Repair Kits 222–774 (UHMWPE/ r ), 222–775
(r ), and 237–916 (UHMWPE/leather) are avail -
able to replace the throat packings. For the best re -
sults, use all the new parts in the kit. Kit parts are
marked with a symbol, for example (3 { ). See page 30.
Repair Kit 222–793 is available to service the intake
valve of Displacement Pumps 222–790, 237–206, and
237–450. For the best results, use all the new parts in
the kit. Kit parts are marked with a symbol, for exam
-
ple (19 }).
1.
Remove the displacement pump from the air motor
as explained on page 14. Place the pump in a
vise, with the jaws on the outlet housing (10).
2. Hold the flats of the priming piston rod (24) with a
12 mm wrench. Using a 22 mm wrench, unscrew
the priming piston nut (30). Slide the priming piston
(25) and piston guide (31) of f the rod. Inspect the
surfaces of the guide (31) and piston (25) for scor -
ing, wear , or other damage.
3. Loosen the packing nut (2) using the wrench (1 10)
supplied, or a hammer and brass rod. Remove the
intake cylinder (23), using an adjustable wrench.
4. Unscrew the intake valve housing (17) from the
cylinder (12), using an adjustable wrench. Pull the
housing of f the pump. The intake check valve as -
sembly (DD) should slide down the priming piston
rod (24) as you remove the housing; if it does not
slide easily , firmly tap on the top of the housing
(17) with a rubber mallet to loosen.
5. Use an o-ring pick to remove the seal (21) from
the intake valve housing (17). Discard the seal;
use a new one for reassembly . Pull the intake
valve seat (22) out the bottom of the housing (17).
If the seat is dif ficult to remove, insert a brass rod
through the top of the housing and drive the seat
out with a hammer .T ake care not to drop the check
valve assembly (DD) as it comes free, and set it
aside for later .
6. Push the displacement rod (1) down as far as pos -
sible, then pull it and the priming piston rod (24)
out of the outlet housing (10) and cylinder (12).
7. Remove the packing nut (2), throat packings (5
and/or 3) and glands (4 and 6) from the outlet
housing (10).
Do not remove the fluid outlet nipple
(8) and o-ring (9) from the housing unless they
need replacement.
8. Unscrew the handle of the bleeder valve (35) from
its housing. Clean the threads and the bleed hole
in the valve housing. It is not necessary to remove
the valve housing from the outlet housing (10).
9. Use a 400 mm adjustable wrench on the flats of
the pump cylinder (12) and unscrew the cylinder
from the outlet housing (10). Remove the o-rings
(1 1). Inspect the inside surface of the cylinder for
wear , scoring or other damage by holding it up to
the light at an angle or running a finger over the
surface.
10. Inspect the outer surfaces of the displacement rod
(1) and priming piston rod (24) for wear , scoring or
other damage by holding them up to the light at an
angle or running a finger over the surface.
11. Use a vise with soft jaws to hold the displacement
rod (1) by its flats. Place a 19 mm wrench on the
flats of the piston and unscrew the piston (13) and
priming piston rod (24) from the displacement rod
(1). Remove the spacer (33). Disassemble the pis -
ton guide (14) from the piston (13).
12. It is not necessary to remove the priming piston
rod (24) from the piston (13) unless your inspec -
tion reveals scoring, wear , or other damage to ei -
ther part. T
o disassemble, place the piston flats in
a vise and unscrew the rod, using a 12 mm wrench
on the flats.
PTFE
PTFE

308–017 17
Service
Fig. 5
1
3
4
2
2
10
11
11
21
22
31
30
23
24
4
5
or
3
6
3
Lips of v-packings must face down.
Throat Packing Detail
12
1
9
25
0425A
35
17
Valve Handle (remove and clean).
See Detail at right.
8
2
2
V alve Housing (do not remove).
4
3
13
33
14
15
DD
16
19
20
18
Detail of Piston and
Intake Check V alve
12
(Ref)
1
(Ref)
24
(Ref)
17
(Ref)
42
11
5Remove
only if damaged.
5
DD

18 308–017
Service
13. Place the flats of the piston seat (16) in a vise. Us -
ing a 13 mm (1/2 in.) dia. brass rod (EE), unscrew
the piston guide (14) from the piston seat (16).
See Fig. 6. Remove the piston seal (15); always
replace with a new one. Inspect the mating sur -
faces of the piston (13) and piston seat (16) for
nicks, scoring or wear .
Fig. 6
14
16
0205
EE
14. T
o disassemble the intake check valve (DD), place
the nut (18) in a vise and unscrew the intake valve
body (19), using a 28 mm wrench. See Fig. 7. Re -
move the seals (42, 20) from the nut and from the
valve body; always replace them with new ones.
Inspect the mating surfaces of the intake valve
body (19) and seat (22) for wear , scoring, or other
damage.
NOTE:
The seal (42) is press-fit in the nut (18) and
may require cutting to ease removal.
15. Inspect all parts for damage and clean with a com -
patible solvent. T o reassemble, refer to page 19.
Fig. 7
19
18
0206

308–017 19
Service
Reassembly (Refer to Fig. 8)
1. Place a 13 mm (1/2 in.) diameter brass rod length -
wise in a vise. Install a new piston seal (15*) on
the piston seat. Apply thread sealant to the
threads of the piston seat. Place the piston guide
(14) securely on the brass rod. Using a 32 mm
crow’ s-foot, screw the piston seat (16) into the pis -
ton guide. T orque to 27–34 N.m (20–25 ft-lb).
2. If it was necessary to remove the priming piston
rod (24) from the piston (13), apply thread sealant
to the threads of the rod. Place the flats of the pis -
ton (13) in a vise. Hold the flats of the rod with a
12 mm wrench, and screw the rod into the piston.
T orque to 45–53 N.m (33–39 ft-lb).
3. Use a vise with soft jaws to hold the displacement
rod (1) by its flats. Install the spacer (33, see the
following note) on the rod. Install the assembled
piston guide/seat on the piston (13). Apply thread
sealant to the threads of the displacement rod, and
screw the piston assembly onto the rod, using a 19
mm wrench on the flats of the piston. T orque to
120–130 N.m (88–95 ft-lb). There will be a small
gap between the top of the piston (13) and the
shoulder of the rod (1).
NOTE: The piston spacer (33) is not required when
pumping fluids with a viscosity greater than 1 million
centipoise.
4.
Screw the handle of the bleeder valve (35) into the
valve housing. The handle has two sets of threads.
When reassembling, be sure to screw the handle
fully into the valve housing.
NOTE: It is not ordinarily necessary to remove the out -
let nipple (8) and o-ring (9*). However , if they were re -
placed because of damage, lubricate the o-ring and
place it on the nipple. Screw the nipple into the outlet
housing (10). T orque to 70–75 N.m (51–55 ft-lb).
5. Lubricate the o-rings (1 1*) and install them on the
cylinder (12). Apply thread lubricant to the top
threads of the cylinder. Using a 400 mm wrench on
the flats of the cylinder , screw it into the outlet
housing (10). T orque to 297–325 N.m (220–240
ft-lb).

20 308–017
Service
6. Lubricate the throat packings and glands, and
install them in the outlet housing (10) one at a time
in the following order
, with the lips of the
v-packings facing down:
the male gland (6 ),
v-packings (see the NOTE below), and the female
gland (4  ). Apply thread lubricant to the packing
nut (2) and install the nut loosely in the outlet
housing.
NOTE:
Refer to page 30 for the correct throat packing
configuration for your pump.
7. Carefully insert the displacement rod (1) into the
bottom of the cylinder (12). Push the rod up into
the cylinder and through the outlet housing (10),
until it protrudes from the packing nut (2). Be care -
ful not to damage the piston seal (15*) while per -
forming this step.
8. Apply thread lubricant to the bottom threads of the
cylinder (12). Be sure the o-ring (1 1*) is in place on
the cylinder . Guide the intake valve housing (17)
up onto the priming piston rod (24) and screw it
onto the cylinder , using an adjustable wrench.
T orque to 297–325 N.m (220–240 ft-lb).
9. With the beveled side facing up, press the seal
(42) into the recess of the intake packing nut (18)
until it snaps into place. The nose of the seal
should be flush with or slightly recessed into the
face of the packing nut.
10. Apply sealant to the threads of the intake packing
nut (18). With the threads facing down toward the
pump intake, slide the nut up onto the priming pis -
ton rod (24) until it clears the flats of the rod.
11. Lubricate a new intake valve seal (20*) and slide it
onto the rod, being careful not to damage the seal
when passing over the flats of the rod. Slide the
seal up until it reaches the packing nut (18). Apply
sealant to the female threads of the intake valve
body (19), and slide it onto the rod until it reaches
the nut (18).
12. Place a 26 mm wrench on the flats of the packing
nut (18) and a 28 mm wrench on the flats of the
valve body (19). Screw the nut into the body , mak -
ing certain they remain in position above the flats
of the rod (24). T orque to 45–53 N.m (33–39 ft-lb).
Slide the assembled intake check valve up the
priming piston rod until it reaches the stop (FF);
this may be dif ficult due to high friction between
the seal and rod.
13. Position the intake valve seat (22) so its large bev -
eled side faces down toward the pump intake.
Slide the seat (22) onto the priming piston rod (24)
and into the intake valve housing (17) until it seats
on the lower lip of the housing. Lubricate a new
seal (21*) and push it up into the gap around the
bottom outer edge of the seat (22).
14. Apply thread lubricant to the threads of the intake
cylinder (23) and screw the cylinder into the intake
valve housing (17), using an adjustable wrench.
T orque to 297–325 N.m (220–240 ft-lb).
15. Slide the priming piston guide (31) onto the rod
(24) until it stops. Then install the priming piston
(25) with the flat side of the priming piston (25)
facing up toward the pump. Apply thread sealant to
the threads of the priming piston rod (24). Hold the
rod steady with a 12 mm wrench on the flats, and
screw the priming piston nut (30) onto the rod with
a 22 mm wrench. T orque to 45–53 N.m (33–39
ft-lb).
16.
Reconnect the displacement pump to the air motor
as explained on page 15.
17. Allow 2 hours for the thread sealant to cure before
returning the pump to service.