Graco NXT Air Motor M02LN0 Parts list manual

Instructions/Parts
NXT®Air Motor 312796S
EN
For use with high performance finishing and coating pumps in hazardous or
non-hazardous locations. For professional use only.
Models M02xxx, M04xxx, M07xxx, M12xxx, M18xxx, and M34xxx
100 psi (0.7 MPA, 7.0 bar) Maximum Working Pressure
See page 3 for model information.
Important Safety Instructions
Read all warnings and instructions in this
manual. For complete warnings and
instructions see your pump or package
manual. Hazard symbols refer to specific
procedure risks. Save all instructions.
ti11838a

Related Manuals
2312796S
Contents
Related Manuals . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Component Identification . . . . . . . . . . . . . . . . . . . . 6
Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Preventive Maintenance Schedule . . . . . . . . . . . 9
Pressure Relief Procedure . . . . . . . . . . . . . . . . . 9
Repair Air Valve . . . . . . . . . . . . . . . . . . . . . . . . . 9
Replace Pilot Valves . . . . . . . . . . . . . . . . . . . . . 13
Repair Air Motor . . . . . . . . . . . . . . . . . . . . . . . . 13
Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Air Motor Parts — All Models . . . . . . . . . . . . . . . . 17
Air Valve Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Kits and Accessories . . . . . . . . . . . . . . . . . . . . . . 21
Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Mounting Hole Diagrams . . . . . . . . . . . . . . . . . . . 23
Technical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Graco Standard Warranty . . . . . . . . . . . . . . . . . . . 26
Graco Information . . . . . . . . . . . . . . . . . . . . . . . . . 26
Related Manuals
Manual Description
312792 Merkur Displacement Pump
312793 Merkur Bellows Displacement Pump
312794 Merkur Pump Assembly
312795 Merkur Bellows Pump Assembly
312797 Merkur Spray Packages, AA and Airless,
Ambient
312798 Merkur Electrostatic Spray Packages
312799 Merkur Bellows Spray Packages, AA
and Airless
313255 Merkur Heated Spray Packages

Warnings
312796S 3
Warnings
The following warnings are for the setup, use, grounding, maintenance, and repair of this equipment. The exclama-
tion point symbol alerts you to a general warning and the hazard symbol refers to procedure-specific risk. Refer back
to these warnings. Additional, product-specific warnings may be found throughout the body of this manual where
applicable.
FIRE AND EXPLOSION HAZARD
Flammable fumes, such as solvent and paint fumes, in work area can ignite or explode. To help prevent
fire and explosion:
• Use equipment only in well ventilated area.
• Eliminate all ignition sources; such as pilot lights, cigarettes, portable electric lamps, and plastic drop
cloths (potential static arc).
• Keep work area free of debris, including solvent, rags and gasoline.
• Do not plug or unplug power cords, or turn power or light switches on or off when flammable fumes are
present.
• Ground all equipment in the work area. See Grounding instructions.
• Use only grounded hoses.
• Hold gun firmly to side of grounded pail when triggering into pail.
• If there is static sparking or you feel a shock, stop operation immediately. Do not use equipment until
you identify and correct the problem.
• Keep a working fire extinguisher in the work area.
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 com-
ponent. See Technical Data in all equipment manuals.
• Use fluids and solvents that are compatible with equipment wetted parts. See Technical Data in all
equipment manuals. Read fluid and solvent manufacturer’s warnings. For complete information about
your material, request MSDS forms from distributor or retailer.
• Check equipment daily. Repair or replace worn or damaged parts immediately with genuine manufac-
turer’s replacement parts only.
• Do not alter or modify equipment.
• 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.
SKIN INJECTION HAZARD
High-pressure fluid from gun, 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 gun at anyone or at any part of the body.
• Do not put your hand over the spray tip.
• Do not stop or deflect leaks with your hand, body, glove, or rag.
• Do not spray without tip guard and trigger guard installed.
• Engage trigger lock when not spraying.
• Follow Pressure Relief Procedure in this manual, when you stop spraying and before cleaning,
checking, or servicing equipment.
WARNING
WARNINGWARNING
WARNING

Warnings
4312796S
PRESSURIZED EQUIPMENT HAZARD
Fluid from the gun/dispense valve, leaks, or ruptured components can splash in the eyes or on skin and
cause serious injury.
• Follow Pressure Relief Procedure in this manual, when you stop spraying and before cleaning,
checking, or servicing equipment.
• Tighten all fluid connections before operating the equipment.
• Check hoses, tubes, and couplings daily. Replace worn or damaged parts immediately.
MOVING PARTS HAZARD
Moving parts can pinch or amputate fingers and other body parts.
• Keep clear of moving parts.
• Do not operate equipment with protective guards or covers removed.
• Pressurized equipment can start without warning. Before checking, moving, or servicing equipment,
follow the Pressure Relief Procedure in this manual. Disconnect power or air supply.
PERSONAL PROTECTIVE EQUIPMENT
You must wear appropriate protective equipment when operating, servicing, or when in the operating area
of the equipment to help protect you from serious injury, including eye injury, inhalation of toxic fumes,
burns, and hearing loss. This equipment includes but is not limited to:
• Protective eyewear
• Clothing and respirator as recommended by the fluid and solvent manufacturer
• Gloves
• Hearing protection
WARNING
WARNINGWARNING
WARNING

Models
312796S 5
Models
Check your motor’s identification plate (ID) for the 6-digit part number of your
motor. Use the following matrix to define the construction of your motor. For
example, motor part number M04LT0 represents an air motor (M), with 400
cc displacement, a 3.5 in. piston diameter and a 2.5 in. stroke (04), low noise
exhaust (L), and DataTrak™monitoring with runaway protection (T). The last
digit (0) is unassigned.
* Uses a smaller muffler. Limited use.
ti12922a
ID
M04 L T 0
First Digit
Second and Third Digits
(displacement, piston
diameter x stroke)
Fourth Digit
(Exhaust Type)
Fifth Digit
(Data Monitoring) Sixth Digit
M
(Air Motor)
02 200 cc, 2.5 in x 2.5 in. F* Flush pump
(limited use)
NNone (Compatible with
DataTrak with Cycle Count)
0
(not
assigned)
04 400 cc, 3.5 in. x 2.5 in. LLow noise TCompatible with DataTrak
with Runaway Protection
07 700 cc, 4.5 in. x 2.5 in. PPark - Vent valve to be
parked in down position
(compatible with DataTrak
with Cycle Count)
12 1200 cc, 6.0 in. x 2.5 in. H200 cc Motor Compatible
with Linear Sensor
18 1800 cc, 7.5 in. x 2.5 in.
34 3400 cc, 7.5 in. x 4.75 in.
Do not operate the air motor without a plumbed
exhaust line or muffler installed.
Air
Motor
Part No. Series
Displacement
(cc)
Stroke
(in.)
Piston
Diameter,
in. (mm)
Low
Noise
Linear
Sensor
Compatible
DataTrak
Cycle Count
Compatible
DataTrak with
Runaway
Protection
Compatible
Park
(Lowers to
down
position)
M02LN0 C 200 2.5 2.5 (63) 
M02LH0 A 200 2.5 2.5 (63)  
M02LT0 A 200 2.5 2.5 (63) 
M04LN0 D 400 2.5 3.5 (89)  
M04LT0 D 400 2.5 3.5 (89)   
M07LN0 D 700 2.5 4.5 (114)  
M07LT0 D 700 2.5 4.5 (114)   
M12FN0 D 1200 2.5 6.0 (152) 
M12LN0 D 1200 2.5 6.0 (152)  
M12LT0 D 1200 2.5 6.0 (152)   
M12LP0 D 1200 2.5 6.0 (152)   
M18LN0 D 1800 2.5 7.5 (191)  
M18LT0 D 1800 2.5 7.5 (191)   
M34LN0 A 3400 4.75 7.5 (191) 

Component Identification
6312796S
Component Identification
Key:
A Air valve
B Air inlet, 1/4 in. npt(f) for M02xxx and M04xxx models,
1/2 in. npt(f) for M07xxx, M12xxx, and M18xxx models
C Muffler (M18xxx models have a second muffler, see inset.
Model M12Fxx has smaller mufflers; not shown.)
D Pilot valve
E Manifold
F Solenoid release button (for DataTrak models with
runaway protection)
G Ground screw
H Solenoid bracket (for DataTrak models with runaway
protection)
J Solenoid (for DataTrak models with runaway protection)
K Reed switch (DataTrak models)
FIG. 1: NXT Air Motor components
A
B
C
D
F
G
H
J
K
ti12645a
E
Model M04LT0 shown
M18xxx models have
two mufflers (C).

Component Identification
312796S 7
Grounding
See FIG. 2. Verify that the ground screw (GS) is attached
and tightened securely to the air motor. Connect the
other end of the ground wire (U) to a true earth ground.
Accessories
Bleed-type master air valve
• Required in your system to relieve air trapped
between it and the air motor when the valve is
closed.
• Be sure the valve is easily accessible from the pump
and located downstream from the air regulator.
Air regulator
Adjusts air pressure to the motor and fluid outlet pres-
sure of pump. Locate it close to the pump. Install a
gauge to read air pressure.
Air filter
Removes harmful dirt and moisture from compressed
air supply.
FIG. 2: Ground wire
GS Uti12914a
Trapped air can cause the pump to cycle unexpectedly,
which could result in serious injury from splashing or
moving parts.

Troubleshooting
8312796S
Troubleshooting
Relieve the pressure before checking or servicing
the equipment.
NOTICE
Check all possible problems and causes before dis-
assembling the pump.
Problem Cause Solution
Air motor will not run. DataTrak solenoid engaged (DataTrak
models with runaway protection).
Push solenoid release button (118).
Remove solenoid and manually
move pin.
Damaged air valve (17). Replace or service air valve (17).
See page 9.
Damaged pilot valve (19). Replace pilot valves (19). See page
13.
Air continuously exhausting
around air motor piston rod.
Damaged u-cups (3, 43). Replace piston rod u-cups (3, 43).
See page 13.
Air continuously exhausting from
muffler.
Damaged air valve plate (105) or cup
(112).
Replace or service air valve (17).
See page 9.
Air motor “bounces” at top of
stroke.
Damaged bottom pilot valve. Replace bottom pilot valve (19). See
page 13.
Air motor “bounces” at bottom of
stroke.
Damaged top pilot valve. Replace top pilot valve (19). See
page 13.
Icing inside motor. Air motor operating at high pressure
or high cycle rate.
Reduce pressure, cycle rate, or duty
cycle of motor.
Reduce dew point of compressed air
in moisture coalescing filter.

Repair
312796S 9
Repair
Preventive Maintenance
Schedule
The operating conditions of your system determine how
often maintenance is required. Establish a preventive
maintenance schedule by recording when and what kind
of maintenance is needed, and then determine a regular
schedule for checking your system.
Pressure Relief Procedure
1. Engage the trigger lock.
2. Close the bleed-type master valve.
3. Disengage the trigger lock.
4. Hold a metal part of the gun firmly to a grounded
metal pail. Trigger the gun to relieve pressure.
5. Engage the trigger lock.
6. Open all fluid drain valves in the system, having a
waste container ready to catch drainage. Leave
drain valve(s) open until you are ready to spray
again.
7. If you suspect the spray tip or hose is clogged or
that pressure has not been fully relieved after follow-
ing the steps above, VERY SLOWLY loosen tip
guard retaining nut or hose end coupling to relieve
pressure gradually, then loosen completely. Clear
hose or tip obstruction.
Repair Air Valve
Replace Complete Air Valve
1. Stop the pump at the middle of its stroke. Relieve
the pressure. See procedure at left.
2. Disconnect the air line to the motor.
3. For motors with DataTrak: Remove screw (32) to
disconnect the reed switch (31) from the air valve
(17).
4. For motors with DataTrak: If equipped with a run-
away protection solenoid, remove two screws (18)
and the solenoid bracket (26). Pull the solenoid (25)
out of the air valve.
• Trapped air can cause the pump to cycle unexpect-
edly, which could result in serious injury from skin
injection or moving parts.
• Do not lift or move motor while pressurized.
FIG. 3: Reed switch assembly & air line removal
ti12727a
31
32
air
line

Repair
10 312796S
5. Remove screws (18). Remove the air valve (17) and
gasket (16*).
6. To repair the air valve, go to Disassemble the Air
Valve, step 1 at right. To install a replacement air
valve, continue with step 7.
7. Align the new air valve gasket (16*) on the mani-
fold, then attach the air valve (17).
8. For motors with DataTrak: If equipped with a run-
away protection solenoid, remember to reattach the
solenoid bracket and the solenoid.
9. For motors with DataTrak: Use screw to attach the
reed switch assembly to the new air valve. Be sure
the sensor cables are connected properly (see
pump or package manual).
10. Reconnect the air line to the motor.
Replace Seals or Rebuild Air Valve
Air Valve Seal Kits are available. See page 21 to order
the correct kit for your pump. Parts are marked †.
Air Valve Repair Kits are available. See page 21 to order
the correct kit for your pump. Parts are marked .
Air Valve End Cap Kits are available. See page 21 to
order the correct kit for your pump. Parts are marked .
Disassemble the Air Valve
1. Perform steps 1-5 under Replace Complete Air
Valve, page 9.
2. See FIG. 5. Use a 2 mm or 5/64 hex key to remove
two screws (109†). Remove the valve plate
(105).
3. M02xxx and M04xxx Motors: Remove the cup
(112) and spring (111).
M07xxx, M12xxx, and M18xxx Motors: Remove
the two-piece cup assembly (112a, b, and c), and
spring (111).
4. Remove the snap ring (110) from each end. Use
the piston to push the end caps (107, 117) out of
the ends. Remove end cap o-rings (106†,
119†).
5. Remove the piston (102). Remove the u-cup seals
(108†) from each end and the detent assembly
(103) and detent cam (104) from the center.
FIG. 4: Solenoid removal
ti12728a
Use a
10 mm hex
26
25
FIG. 5: Air plate removal
109†
105
112
111
ti12751a
112c
112b
112a