GORMAN-RUPP PUMPS AMT 337 Series Assembly instructions

Specications Information and Repair Parts Manual 337 Series and 338 Series
3370-250-00 1 5/2022
Please read and save this Repair Parts Manual. Read this manual and the General Operating Instructions carefully before attempting to assemble, install, operate
or maintain the product described. Protect yourself and others by observing all safety information. The Safety Instructions are contained in the General Operating
Instructions. Failure to comply with the safety instructions accompanying this product could result in personal injury and/or property damage! Retain instructions
for future reference. AMT reserves the right to discontinue any model or change specications at any time without incurring any obligation.
©2022 AMT Pump Company, A Subsidiary of The Gorman-Rupp Company, All Rights Reserved.
Periodic maintenance and inspection is required on all pumps to insure proper operation. Unit must be clear of debris and sediment. Inspect for leaks and loose bolts. Failure to do so
voids warranty.
Diaphragm Pumps
.
UNPACKING
After unpacking the unit, inspect carefully for any damage that may have
occurred during transit. Check for loose, missing or damaged parts.
Specic Safety Information for Gasoline Engine Driven
Pumps
1. Carefully read the instruction manuals supplied by the engine
manufacturer before attempting to assemble, disassemble or operate
the engine or any other part. The “Warning” and “Caution” statements
in this manual signal potentially hazardous conditions to the operator or
equipment. Know when these conditions can exist. Take necessary steps
to protect personnel, as well as equipment.
Gasoline is a highly combustible fuel. Use it with care! The improper
use, handling and/or storage of gasoline can be dangerous. Help prevent
accidents by following these safety rules:
• Use gasoline only as a fuel, never as a cleaning uid.
• Always use an approved container to hold or store gasoline. Never
store gasoline in familiar containers such as milk gallons or soda pop
bottles
• Never store gasoline near a heater or an open ame.
• When storing or using gasoline, make sure container is out of the
reach of children.
• Never add gasoline to a running or hot engine. Spilled gasoline on
a hot engine may cause a re or an explosion. Fill gasoline tank
DESCRIPTION
These diaphragm pumps are high capacity, self-priming (to 25 ft. lift), portable units shipped completely assembled (except for handle). The pumps are used
for operation with uids mixed with abrasive solids such as sand, silt, mud, sludge and waste. Not for use with pumping cement or mortar. Handles liquids from
40º to 180º F (4º to 82 º C). Pump is capable of handling solids up to 1-5/8” diameter. For use with water and other non-ammable uids compatible with pump
component materials.
outdoors and wipe up any spills.
• Have a re extinguisher nearby. Be sure extinguisher is in operating
condition – check the pressure gauge or indicator. Be familiar with
its proper use. Consult the local re department for the correct
type of extinguisher for your application. Extinguishers rated ABC
by the National Fire Protection Association are appropriate for all
applications.
• On permanent installations, be sure all fuel supplies have a positive
shuto󰀨 valve. Fuel lines must be of steel piping, adequately secured
and free from leaks. Do not use copper piping on exible lines as
copper becomes hardened and brittle and will break. Use black
pipe on natural gas or gaseous fuels, but not on gasoline or diesel
fuels. Piping at the engine should be a suitable exible line that is
compatible with the uid.
Positively no smoking!
2. Check engine oil, fuel levels and gear box oil levels before initial startup
each day. Stay away from moving parts due to the danger of becoming
caught in moving parts. Avoid loose jackets, shirts, sleeves and ties. Make
sure all nuts and bolts are secure. Keep power shields and guards in
place. If adjustment MUST be made while the unit is running, use extreme
caution around hot manifolds, moving parts, etc.
3. Do not work with this equipment when mentally or physically fatigued.
Model Driver Type Material Diaphragm Check Valve Gear Box Plunger Bearing NPT
338Z-96 Hatz 1B30 Diesel Aluminum Thermoplastice/TPE Neoprene Oil Bath Needle 2”
338G-96 Honda GX120 Aluminum Thermoplastice/TPE Neoprene Oil Bath Needle 2”
338L-96 LCT 280CC Aluminum Thermoplastice/TPE Neoprene Oil Bath Needle 2”
338E-96 1.5 HP 115VAC @ 60 HZ Aluminum Thermoplastice/TPE Neoprene Oil Bath Needle 2”
338T-96 1.5 HP, 3PH 208-
230/460VAC @ 60HZ Aluminum Thermoplastice/TPE Neoprene Oil Bath Needle 2”
337G-96 Honda GX120 Aluminum Thermoplastice/TPE Neoprene Oil Bath Needle 3”
337H-96 Honda GX160 Aluminum Thermoplastice/TPE Neoprene Oil Bath Needle 3”
337L-96 LCT 280CC Aluminum Thermoplastice/TPE Neoprene Oil Bath Needle 3”
337Z-96 Hatz 1B30 Diesel Aluminum Thermoplastice/TPE Neoprene Oil Bath Needle 3”
337E-96 1.5 HP 115 VAC @ 60 HZ Aluminum Thermoplastice/TPE Neoprene Oil Bath Needle 3”
337T-96 1.5 HP, 3PH 208-
230/460VAC @ 60HZ Aluminum Thermoplastice/TPE Neoprene Oil Bath Needle 3”
NOTE: Driver is subject to change without notice, see labels and manual with driver for operation, specications, maintenance and warranty.

Specications Information and Repair Parts Manual 337 Series and 338 Series
3370-250-00 2 5/2022
4. Be careful not to touch the exterior of the engine, especially the mu󰀪er
and the area around it. It is hot enough to be painful or cause injury.
5. To prevent accidental starting, always remove the spark plug or disconnect
and ground the spark plug wire before working on the engine or the
equipment driven by the engine.
6. DO NOT RUN THE ENGINE IN AN ENCLOSED AREA!! Exhaust gases
contain carbon monoxide, which is an odorless and deadly gas that will
cause death if breathed too long. If equipment is located in an enclosed
area with an exhaust line to the outside, regularly check the exhaust
system for leaks. Be sure the area is well ventilated.
7. If the gas engine is equipped with a spark arrester screen in the mu󰀪er, it
should be inspected for wear periodically and replaced when necessary.
Specic Safety Information for Electric Motor Driven Pump
1. This unit is not waterproof and is not intended to be used in potentially wet
locations. The motor is designed to be used in a clean dry location with
access to an adequate supply of cooling air. Ambient temperature around
the motor should not exceed 104º F (40º C). For outdoor installations,
motor must be protected by a cover that does not block air ow to
and around the motor. This unit is not weatherproof nor is it able to be
submersed in water.
2. When wiring an electrically driven pump, follow all electrical and safety
codes, as well as the most recent United States National Electrical Code
(NEC) and the Occupational Safety and Health Act (OSHA).
Risk of electrical shock! Never connect the green (or green and yellow)
wire to a live terminal.
3. To reduce the risk of electric shock, the motor must be securely and
adequately grounded!. This can be accomplished by either: (1) inserting
plug (portable) directly into a properly installed and grounded 3-prong
grounding-type receptacle (as shown in Figure 2); (2) permanently wiring
the unit with a grounded metal raceway system; (3) using a separate
ground wire connected to the bare metal of the motor frame; or (4) other
suitable means. The green (or green and yellow) conductor in the cord is
the grounding wire. The motor must be securely and adequately grounded
for your protection against shock hazards! Where a 2-prong wall receptacle
is encountered, it must be replaced with a properly grounded 3-prong
receptacle with a grounded 3-prong receptacle installed in accordance
with the National Electrical Code and local codes and ordinances.
To ensure a proper ground, the grounding means must be tested by a
qualied electrician. Use only 3-wire extension cords that have 3-prong,
grounding-type plugs and 3-pole receptacles that accept the equipment
plug.
4. All wiring should be performed by a qualied electrician.
Figure 2 Grounding Methods
An incorrect connection may cause an electric short, produce an electrical
shock or burn out the pump motor, resulting in property damage and/or
personal injury.
5. Protect electrical cord from sharp objects, hot surfaces, oil and chemicals.
Avoid kinking the cord. Replace or repair damaged or worn cords
immediately.
6. Provide safety shields on all moving and electrical parts to prevent
personal injury.
7. Keep ngers and foreign objects away from ventilation and other
openings. Do not insert any objects into the motor.
8. Use wire of adequate size to minimize voltage drop at the motor.
9. Disconnect power before servicing a motor or its load. If the power
disconnect is out of sight, lock it in the open position and tag it to prevent
unexpected application of power.
10. Do not touch an operating motor. Modern motors are designed to operate
at high temperatures.
General Safety Information (All Units)
1. Know the pump application, limitations and potential hazards.
Do not use to pump ammable or explosive uids such as gasoline,
fuel oil, or kerosene, etc. Do not use in ammable and/or explosive
atmospheres. Pump should only be used with liquids compatible with
pump component materials. Failure to follow this warning can result in
personal injury and/or property damage.
2. Make certain that the power source conforms to the requirements of your
equipment.
3. Provide adequate protection and guarding around moving parts.
4. Disconnect power before servicing.
5. Release all pressure within the system before servicing any component.
6. Drain all liquids from the system before servicing.
7. Secure the discharge line before starting the pump. An unsecured
discharge line will whip, possibly causing personal injury and/or property
damage.
8. Check hoses for weak or worn condition before each use, making certain
that all connections are secure.
9. Periodically inspect pump and system components. Perform routine
maintenance as required (see Maintenance Section).
10. Provide a means of pressure relief for pumps whose discharge line can
be shut o󰀨 or obstructed.
11. Personal Safety:
• Wear safety glasses at all times when working with pumps.
• Wear a face shield and proper apparel when pumping hazardous
chemicals.
• Keep work area clean, uncluttered and properly lighted - replace all
unused tools and equipment.
• Keep visitors at a safe distance from the work area.
• Make workshop childproof – with padlocks, master switches and by
removing starter keys.
12. For air drive units follow Safety Information in instruction sheet supplied
with air motor.
ASSEMBLY
1. HANDLE (Refer to Figure A)
• Place handle (Ref. No. A11) on gearbox foot ange and align holes.
• Install two hex screws (Ref. No. A12) at washers (Ref. No. A13) and
hex nuts (Ref. No. A14), tighten screws.
2. ROTATING SUCTION/DISCHARGE PORTS (OPTIONAL) (Refer to
Figure A,W,P)
Diaphragm Pumps

Specications Information and Repair Parts Manual 337 Series and 338 Series
3370-250-00 3 5/2022
Diaphragm Pumps
In some applications, it may be preferable to have suction/discharge ports
rotated 90 degrees to be in line with driver. If so, proceed as follows:
• Remove four hex cap screws (Ref. No. A8) and hex nut (Ref. No. A9)
from pump assembly to separate pump well (Ref. No. A3) from pump
base (Ref. No. A7).
• Rotate pump well 90 degrees clockwise so that driver is positioned over
top of discharge plate (Ref. No. W6).
• Be sure that pump well, base and diaphragm (Ref. No. P13) are aligned
properly with one another. Then, reinstall four hex cap screws and hex
nuts and tighten.
GEAR BOX OIL (Refer to Figure A,G)
3. Place pump on a level surface. Fill pump gear box (Ref. No. A1) with gear
box oil before the pump is operated. Gear oil must meet requirements of
API GL-5 and military specication MIL-L-2105B. Remove level plug (Ref.
No. G5). Pour gear oil into gear box slowly until oil comes out of ll port.
Warranty on this unit is void unless the gear box is lubricated with
appropriate gear oil listed above. DO NOT OVER FILL!
INSTALLATION
NOTE: In any installation where property damage can occur by pumps not
operating due to power outages, discharge line freezing or any other reason, a
backup system(s) and/or warning system(s) should be used.
1. Place the pump on a level, solid foundation, locating it as close to the
liquid as possible, making the suction line as short and direct as possible.
2. Install pipe nipples (Ref. No. A35) so the smoother side of pipe end faces
the suction and discharge hose.
Maximum discharge head is 25 feet or 10.9 psi. Operation over this head
or pressure will cause pump to stall and/or gearbox damage. Use only
rigid hoses.
3. Attach suction piping to the suction inlet (Ref. No. W2) and discharge
piping to the discharge outlet (Ref. No. W6). The suction line should
be positioned such that there is a continual upward slope from the uid
source to the pump. Avoid using loops or sections of pipe or ttings, which
might permit air to become trapped.
NOTE: If hose is used, be sure to use reinforced hose on both the suction
and discharge. DO NOT USE canvas or similar collapsible materials. NEVER
USE PIPE REDUCER; PIPE SIZE MUST BE EQUAL TO OR LARGER THAN
PUMP PORT SIZE. Suction line must be airtight so that air cannot leak in and
destroy priming vacuum. On a permanent installation where piping is used,
always connect a piece of exible hose between pump and piping so pump is
free to move slightly.
4. It is advisable to use a strainer (Ref. No. A36) on the inlet end of the
suction hose or pipe. A properly sized strainer is supplied with this unit
and should be used at all times to prevent damage. Keep the strainer
clean. If possible, suspend it to keep it from becoming clogged with muck,
roots, debris or leaves. It is best to keep hose free of kinks as they will
restrict ow and add excess loading to pump and gearing.
5. GASOLINE ENGINE UNITS: Follow all instructions in the engine manual
before starting the engine. Fill engine with oil, gasoline, etc.
ELECTRIC MOTOR UNITS: It is strongly recommended that this unit is
plugged into a G.F.I. (Ground Fault Interrupter) circuit. Consult your local
electrician for installation and availability.
6. Input RPM (to pump) – Input RPM must be between 1750 and 2750 RPM.
Final pump speed will be 40 strokes/min. with a 1750 RPM input and 60
strokes/min. with a 2750 RPM input.
Do not exceed 60 strokes per minute with the diaphragm pump.
OPERATION
Operate the diaphragm pump in an upright position only.
1. This diaphragm pump is capable of priming “dry” up to fteen feet; it will
prime much faster when it is lled with clean water through priming cap
(Ref. No. W5). Primed, it can lift to 25 feet.
2. Activate unit following engine or air motor manual or turning unit on if
electrical.
Do not control discharge capacity with a valve or similar device.
CLEARING JAM-UP
If large solids or an accumulation of sand or other sediment becomes lodged
in the pump well (Ref. No. A3) preventing the plunger arm (Ref. No. A2) from
making a full stroke, the pump should be thoroughly cleaned as described
in “If Pump Stalls” shown below. Refer to parts list and illustration for parts
identication.
If pump has stopped or stalled for any unknown reason, clean out pump
cavity thoroughly. Failure to comply with the “caution” could result in
damage to crank (Ref. No. P5/P9), plunger arm (Ref. No. P1) or other parts
of assembly.
1. IF PUMP STALLS:
• Remove four bolts (Ref. No. A8). Seperate pump well from pump
body.
• Clean obstruction and all debris from pump well assembly (Ref. No.
A3).
• Reassemble pump in reverse order of disassembly and return to
service.
2. IF PLUNGER ARM (Ref. No. P1) SEIZES AND GEAR BOX OUTPUT
SHAFT (Ref. No. G8) TURNS IN CRANK (Ref. No. P5):
• Remove guard (Ref. No. A4) by loosening screws (Ref. No. A5).
• Disassemble pump and clean as described in steps above stalled
engine jam up.
• Torque the crank lock screw (Ref. No. P7) to 70 foot pounds with an
appropriate torque wrench (see Figure 3).
Figure 3
• Reassemble the pump in reverse order of disassembly and return
to service.
Pump jamming with an over-torqued lock screw may cause internal
damage. Under torqueing may allow the output shaft to spin and wear
parts necessitating replacement.

Specications Information and Repair Parts Manual 337 Series and 338 Series
3370-250-00 4 5/2022
MAINTENANCE
Make certain that unit is disconnected from power source before
attempting to service or remove any component.
1. Check gear box oil level every 20 hours of operation or at least once a
week; more often if any leakage is detected around the gear box. Change
gearbox oil after the rst 40 hours of operation. Fill to the oil level plug.
Change gearbox oil every 350 hours of operation.
2. The plunger bearing (Ref. No. P3) must be greased (any automotive
grease) after every 8 hours of use. Remove guard (Ref. No. A4) by
loosening two screws (Ref. No. A5). Grease tting on end of bearing; will
be visible after removing guard. Bearing may be cleaned and kept well
lubricated by pumping grease slowly into tting until new grease oozes out
between bearing and journal.
3. During freezing weather, be sure to drain the pump when it is not running.
Remove discharge hose and tip unit towards discharge side.
4. Keep pump clean. After use with liquids containing foreign materials, ush
with clean water.
REPLACEMENT OF FLAPPER VALVE
(Ref. No. W9)
1. Remove two bolts (Ref. No. W3) and remove suction priming plate (Ref.
No. W2). Replace apper (Ref. No. W9) on pin (Ref. No. W8) to locate on
suction plate.
2. Remove two bolts (Ref. No. W7) and remove discharge plate (Ref. No.
W6). Replace apper valve on pin (Ref. No. W8) to locate valve on pump
well (Ref. No. W1).
REPLACEMENT OF DIAPHRAGM
(Ref. No. P13)
1. Remove guard (Ref. No. A4) by loosening screws (Ref. No. A5).
2. Rotate pump until plunger arm (Ref. No. A2) is in the down position.
3. Remove pump well (Ref. No. A3) by removing screws (Ref. No. A8).
4. Remove diaphragm by removing four nuts (Ref. No. P12) from studs (Ref.
No. P11).
5. Replace diaphragm and reverse steps 1 through 4 for reassembly.
GEAR BOX OVERHAULING
A completely assembled gear box is available as a replacement part (Ref. No.
G28).
DISASSEMBLY
1. Remove diaphragm (Ref. No. P13) as described in “Replacement of
Diaphragm”.
2. Remove crank (Ref. No. P5) by loosening hex head screw (Ref. No. P7).
Use screwdriver in slot of crank to release clamp on output shaft (Ref.
No. G8).
3. Drain oil from gear box by removing drain plug (Ref. No. G4).
4. Remove driver (Ref. Nos. A28/A32) from adapter (Ref. No. G26) by
removing four bolts (Ref. No. A27) plus 4 additional bolts (Ref. No. A29)
from engine mount bracket (Ref. No. A16) for gas driver models. Slide
driver back from adapter until driver shaft disengages pinion (Ref. No.
G20).
5. Remove adapter by removing four bolts (Ref. No. G27).
6. Remove gear box from pump base (Ref. No. A7) by removing four bolts
(Ref. No. A6).
7. Remove pinion/bearing assembly (Ref. Nos. G15, G20, G24) by pulling
straight out. Use a slide hammer puller gripping in pinion groove
Diaphragm Pumps
8. Remove twelve screws (Ref. No. G3) holding gear box halves (Ref. Nos.
G1 & G2) together.
9. Carefully separate gearbox halves; input (Ref. No. G2) and output (Ref.
No. G1).
10. Remove gasket (Ref. No. G22).
11. Remove output shaft/bearing assembly (Ref. Nos. G8, G9, G10, G11,
G12, G13) and idler pinion/bearing assembly (Ref. Nos. G13, G14, G17,
G18, G19).
12. Remove output shaft oil seal (Ref. No. G23) from output housing.
13. Remove needle bearing (Re. No. G16) from inut housing.
14. Remove bearing (Ref. No. G15) from end of input pinion shaft (Ref. No.
G20).
15. Remove bearings (Ref. Nos. G13 & G14) from ends of idler pinion shaft
(Ref. No. G17).
16. Remove internal spur gear (Ref. No. G19) and key (Ref. No. G18) from
idler pinion shaft.
17. Remove retaining ring (Ref. No. G10) and bearings (Ref. Nos. G12 &
G13) from ends of output shaft (Ref. No. G8).
18. Remove output gear (Ref. No. G11) and key (Ref. No. G9) from output
shaft.
REASSEMBLY
1. Assemble input pinion/bearing assembly, idler pinion/bearing assembly
and output shaft/bearing assembly.
2. Install output shaft oil seal into gearbox output half. Lubricate lip seal.
Install needle bearing in gear box input half.
3. Slide output shaft through lip seal. Start output bearing in bore in gear
box output half. Position idler pinion bearing assembly in its bore in output
half. Simultaneously press both assemblies into output half.
4. Install gasket on output half.
5. Position gear box input half; align shaft bearings with bearing bores.
Press gear box halves together, align pins in output half with pin bore in
input half.
6. Secure halves together with twelve screws.
7. Slide input pinion/bearing assembly into bore in gear box input half.
Rotate pinion during installation to make sure gear teeth align with internal
spur gear teeth.
8. Reassemble gear box to pump base with four bolts.
9. Reassemble adapter to gear box with four bolts.
10. Align driver shaft key (Ref. No. A26) with keyway in pinion. Slide driver
into pinion, secure to adapter with four bolts (Ref. No. A27).
• (Gas engine only) Attach engine to engine mount with four additional
screw assemblies (Ref. No. A29).
11. Reassemble crank to output shaft as described under “Operation” section.
12. Replace diaphragm as described under “Replacement of Diaphragm”
section.
13. Fill gear box with oil as described under “Assembly” section.
14. Pump should be checked daily, weekly, monthly for proper operation.
NOTE: Only qualied service personnel should attempt to repair this unit.
Improper repair and/or assembly can cause pump damage, driver damage
and/or an electrical shock hazard depending on model.

Specications Information and Repair Parts Manual 337 Series and 338 Series
3370-250-00 5 5/2022
Diaphragm Pumps
Symptom Possible Cause(s) Corrective Action
Pump will not prime or retain 1. Air leak in suction line 1. Repair or replace
prime after operating 2. Defective apper valves 2. Replace
3. Clogged foot valve or strainer 3. Clean or replace
4. No liquid in suction line 4. Fill suction line & pump with liquid
5. Material jammed in pump well 5. Clean (See Maintenance)
Flow rate is slow 1. Incorrect driver speed 1. Increase speed (see Specications)
2. Piping is fouled or damaged 2. Clean or replace
3. Clogged pump 3. Clean
4. Discharge line restricted or undersized 4. Flush out piping or replace
5. Collapsible discharge hose 5. Replace with rigid or non-collapsible
hose
6. Too many bends 6. Straighten hose
7. Lines are too long 7. Shorten lines
Pump runs but no uid 1. Faulty suction piping 1. Replace
2. Pump located too far from uid source 2. Place pump closer to source
3. Gate valve closed 3. Open gate valve
4. Clogged strainer 4. Clean or replace
5. Discharge height too great 5. Lower discharge height
Pump starts and stops pumping 1. Leak in suction line 1. Repair
2. Leak in foot valve 2. Repair or replace
3. Diaphragm has a crack or hole 3. Replace
4. Defective or clogged apper valves 4. Clean or replace
Excessive noise while pump in operation 1. Pump not secured to rm foundation 1. Secure properly
2. Restricted suction line 2. Clean or correct
Pump stalls repeatedly or 1. Discharge height over 25 feet of head 1. Lower height (see Specications)
stops for no apparent reason 2. Material jammed in pump well 2. Clean out pump well (See Operation &
Maintenance section)

Specications Information and Repair Parts Manual 337 Series and 338 Series
3370-250-00 6 5/2022
For Repair Parts contact dealer where pump was purchased.
Please provide following information:
-Model Number
-Serial Number (if any)
Part description and number as shown in parts list
Assembled Pump - Figure A
Diaphragm Pumps

Specications Information and Repair Parts Manual 337 Series and 338 Series
3370-250-00 7 5/2022
Part Number for Models
Ref 3” Engine 3” Motor 2” Engine 2” Motor
No. Description Driven Pump Driven Pump Driven Pump Driven Pump Qty
A1 Gearbox/Gearbox Feet Assembly Ref. Page 8 to 11 Ref. Page 8 to 11 Ref. Page 8 to 11 Ref. Page 8 to 11 1
A2 Plunger Diaphragm Assembly Ref. Page 12 & 13 Ref. Page 12 & 13 Ref. Page 12 & 13 Ref. Page 12 & 13 1
A3 Well Assembly Ref. Page 14 & 15 Ref. Page 14 & 15 Ref. Page 14 & 15 Ref. Page 14 & 15 1
A4 Plunger Guard / Kit 3370-102-92 3370-102-92 3370-102-92 3370-102-92 1
A5 1/4-20x3/4 Screw Incl. w/Ref. A4 Incl. w/Ref. A4 Incl. w/Ref. A4 Incl. w/Ref. A4 2
A6 1/2-13x3/4 Hex Flange Screw 1766-065-00 1766-065-00 1766-065-00 1766-065-00 4
A7 Base 3354-001-00 3354-001-00 3360-020-01 3360-020-01 1
A8 1/2-13x2-1/4 Hex Head Bolt Grade-5 1766-016-00 1766-016-00 1766-016-00 1766-016-00 4
A9 1/2-13 Hex Nut 1782-004-00 1782-004-00 1782-004-00 1782-004-00 4
A10 Washer (not shown) 1798-002-00 1798-002-00 1798-002-00 1798-002-00 4
A11 Handle / Kit 3370-116-90 3370-116-90 3370-116-90 3370-116-90 1
A12 1/2-13x1-3/4 Hex Head Bolt incl w/A11 incl w/A11 incl w/A11 incl w/A11 2
A13 1/2 Flat Washer incl w/A11 incl w/A11 incl w/A11 incl w/A11 2
A14 1/2-13 Hex Nut incl w/A11 incl w/A11 incl w/A11 incl w/A11 2
A15 Mount Brace 3354-107-00 3354-107-00 3354-107-00 3354-107-00 2
A16 Engine Mount 3354-108-00 3354-108-00 3354-108-00 3354-108-00 1
A16 Engine Mount Kit for Hatz Diesel 335Z-101-90 N/A 335Z-101-90 N/A 1
A17 Wheel Bracket 3354-109-00 3354-109-00 3354-109-00 3354-109-00 2
A18 Wheel 1663-000-00 1663-000-00 1663-000-00 1663-000-00 2
A19 5/8-11x4 Hex Head Bolt 1769-000-00 1769-000-00 1769-000-00 1769-000-00 2
A20 5/8 Flat Washer 1799-000-00 1799-000-00 1799-000-00 1799-000-00 2
A21 5/8-11 Hex Nut 1782-022-00 1782-022-00 1782-022-00 1782-022-00 2
A22 5/16-18x3/4 Hex Flange Screw 1745-002-00 1745-002-00 1745-002-00 1745-002-00 4
A23 1/4-20x3 Hex Bolt 1734-013-00 1734-013-00 1734-013-00 1734-013-00 2
A24 1/4 Flat Washer 1789-000-00 1789-000-00 1789-000-00 1789-000-00 2
A25 1/4-20 Hex Nut 1776-000-00 1776-000-00 1776-000-00 1776-000-00 2
A26 3/16x1-1/2 Square Key 1517-001-00 1517-001-00 1517-001-00 1517-001-00 1
A27 5/16-24x3/4 Hex Flange Screw 1752-000-00 N/A 1752-000-00 N/A 4
A27 3/8-16x1 Hex Flange Screw N/A 1755-002-00 N/A 1755-002-00 4
A28 Engine 3/4 Keyed PTO See Chart N/A See Chart N/A 1
A29 5/16-18x1-1/2 Hex Bolt 1748-000-00 N/A 1748-000-00 N/A 4
A30 5/16 Flat Washer 1790-000-00 N/A 1790-000-00 N/A 4
A31 5/16-18 Hex Nut 1785-000-00 N/A 1785-000-00 N/A 4
A32 Motor - 1 Phase N/A 1626-095-00 N/A 1626-095-00 1
Motor - 3 Phase N/A 1627-039-00 N/A 1627-039-00 1
A33 Cord Assembly N/A 335E-352-90 N/A 335E-352-90 1
A34 Switch Assembly (not shown) N/A 335E-350-90 N/A 335E-350-90 1
A35 Nipple Pack (2 NPT nipples) (not shown) 3270-173-90 3270-173-90 C366-999-90 C366-999-90 1
NPT x BSPT Nipple pack (2 nipples) C370-999-90 C370-999-90 C369-999-90 C369-999-90 opt
A36 Suction Strainer (not shown) 1680-000-00 1680-000-00 C230-170-00 C230-170-00 1
Repair Parts List - Assembled Pump (Reference Figure A)
Ref 3” Engine 2” Engine
No. Description Driven Pump Driven Pump Part Number Qty
A28 Honda GX120UT1QX2 337G-96 338G-96 1630-007-00 1
A28 Honda GX160UT1QX2 337H-96 N/A 1639-017-00 1
A28 LCT280CC 337L-96 338L-96 1630-070-00 1
A28 Hatz 1B30 337Z-96 338Z-96 1630-037-90 1
Honda GX160 Spark Arrestor Kit (not shown) 337H-96 N/A 1639-001-90 1
Repair Parts List - Engine Chart

Specications Information and Repair Parts Manual 337 Series and 338 Series
3370-250-00 8 5/2022
For Repair Parts contact dealer where pump was purchased.
Please provide following information:
-Model Number
-Serial Number (if any)
Part description and number as shown in parts list
Gearbox - Figure G
Diaphragm Pumps

Specications Information and Repair Parts Manual 337 Series and 338 Series
3370-250-00 9 5/2022
Repair Parts List - Gearbox (Reference Figure G)
Ref 3” Pumps 2” Pump
No. Description Part Number Part Number Qty
G1 Gearbox Output Half 3370-090-01 3370-090-01 1
G2 Gearbox Input Half 3370-091-01 3370-091-01 1
G3 1/4-20x1 Hex Flange Screw 1730-002-00 1730-002-00 12
G4 1/4 NPT Plug (drain) 1767-002-00 1767-002-00 1
G5 1/2 NPT Plug and Oring (ll / oil level) 3SXB-170-90 3SXB-170-90 1
G6 1/4 NPT Vented Plug 1767-009-00 1767-009-00 1
G7 Lift Bracket 3354-106-00 3354-106-00 1
G8 Output Shaft 3354-140-00 3354-141-00 1
G9 Woodru󰀨 Key #1008 2141-000-00 2141-000-00 1
G10 External Retaining Ring SH-112 1806-064-00 1806-064-00 1
G11 Output Gear 3354-120-00 3354-120-00 1
G12 Bearing-Open 35x80x21 #6307 JEM 3354-190-00 3354-190-00 1
G13 Bearing-Open 20x52x15 #6304 JEM 3354-191-00 3354-191-00 2
G14 Bearing-Open 15x42x13 #6302 JEM 3354-192-00 3354-192-00 1
G15 Bearing-Open 35x62x14 #6007 JEM 3354-194-00 3354-194-00 1
G16 Bearing-Open 30x37x12 Needle 3370-094-00 3370-094-00 1
G17 Idler Pinion Shaft 3354-121-00 3354-121-00 1
G18 Woodru󰀨 Key #406 2157-000-00 2157-000-00 1
G19 Internal Spur Gear 2149-000-00 2149-000-00 1
G20 Input Pinion (3/4 keyed engine) 3370-122-00 3370-122-00 1
G20 Input Pinion (5/8 keyed 56C motor) 3370-123-00 3370-123-00 1
G21 1/4x1 Dowel Pin 1717-002-00 1717-002-00 2
G22 Gasket 3354-300-00 3354-300-00 1
G23 Oil Lip Seal 1-1/4x1-3/4x1/4 2148-000-00 2148-000-00 1
G24 Oil Lip Seal 40x62x8 2148-001-00 2148-001-00 1
G25 1/4-20x1/4 Set Screw 1711-001-00 1711-001-00 1
G26 Adapter (engine) 3370-093-01 3370-093-01 1
G26 Adapter (56C motor) 3370-092-00 3370-092-00 1
G27 5/16-18x3/4 Hex Flange Screw 1745-002-00 1745-002-00 4
G28 Assembled Gearbox for Gas Engine Models 3370-090-96 3380-090-96 1
(includes Ref. Nos. G1 thru G25)
G28 Assembled Gearbox for Electric Models 3370-091-96 3380-091-96 1
(includes Ref. Nos. G1 thru G25)

Specications Information and Repair Parts Manual 337 Series and 338 Series
3370-250-00 10 5/2022
For Repair Parts contact dealer where pump was purchased.
Please provide following information:
-Model Number
-Serial Number (if any)
Part description and number as shown in parts list
Gearbox Feet - Figure L
Diaphragm Pumps

Specications Information and Repair Parts Manual 337 Series and 338 Series
3370-250-00 11 5/2022
Repair Parts List - Gearbox Feet (Reference Figure L)
Ref 3” Pumps 2” Pump
No. Description Part Number Part Number Qty
L1 Steel leg - Left 3370-101-00 3370-101-00 1
L2 Steel leg - Right 3370-100-00 3370-100-00 1
L3 Guard Bracket 3370-102-00 3370-102-00 1
L4 1/2-13x3/4 Hex ange screw 1766-065-00 1766-065-00 4
L5 1/4-20X1/2 Screw 1715-001-00 1715-001-00 2
L6 1/4-20x3/4 Screw 1719-000-00 1719-000-00 2
L7 1/4-20 Flange nut 1776-000-00 1776-000-00 2
L8 1/4-20x3/4 Hex ange screw 1722-000-00 1722-000-00 2
L9 1/4-20 Clip nut 1769-011-00 1769-011-00 2
L10 5/16x3/4 Spring pin 1769-010-00 1769-010-00 2

Specications Information and Repair Parts Manual 337 Series and 338 Series
3370-250-00 12 5/2022
For Repair Parts contact dealer where pump was purchased.
Please provide following information:
-Model Number
-Serial Number (if any)
Part description and number as shown in parts list
Plunger Assembly - Figure P
Diaphragm Pumps

Specications Information and Repair Parts Manual 337 Series and 338 Series
3370-250-00 13 5/2022
Repair Parts List - Plunger Assembly (Reference Figure P)
Ref 3” Pumps 2” Pump
No. Description Part Number Part Number Qty
P1 Plunger 2134-000-02 3360-090-02 1
P2 Retaining Ring 3350-190-00 3360-191-00 1
P3 Plunger Bearing 2138-000-90 3360-190-90 1
(includes Ref. No. P4)
P4 Bearing Lock Nut Incl. w/Ref. P3 Incl. w/Ref. P3 1
P5 Crank / Crank Assembly Kit 2140-000-90 3360-094-90 1
(includes Ref. Nos. P6, P7, P8, & P9)
P6 5/16-18x1/2 Socket Set Screw Incl. w/ Ref.P5 Incl. w/ Ref.P5 1
P7 1/2-13 Hex Head Cap Screw Grade-5 Incl. w/Ref. P5 Incl. w/Ref. P5 1
P8 1/2 Lock Washer Incl. w/Ref. P5 Incl. w/Ref. P5 1
P9 Bearing Shim Incl. w/Ref. P5 Incl. w/Ref. P5 1
P10 Diaphragm Retaining Plate 3370-020-00 3380-092-00 1
P11 7/16-14x2 Stud 1766-007-00 N/A 4
P11 3/8-16x2 Stud N/A 1760-012-00 4
P12 7/16 Heavy Hex Nut 1766-036-00 N/A 4
P12 3/8-16 Hex Nut N/A 1780-000-00 4
P13 Diaphragm 3370-300-00 3380-300-00 1

Specications Information and Repair Parts Manual 337 Series and 338 Series
3370-250-00 14 5/2022
For Repair Parts contact dealer where pump was purchased.
Please provide following information:
-Model Number
-Serial Number (if any)
Part description and number as shown in parts list
Well Assembly - Figure W
Diaphragm Pumps

Specications Information and Repair Parts Manual 337 Series and 338 Series
3370-250-00 15 5/2022
Repair Parts List - Well Assembly (Reference Figure W)
Ref 3” Pumps 2” Pump
No. Description Part Number Part Number Qty
W1 Well 2120-001-00 3360-001-00 1
W2 Suction Plate 2123-000-00 3360-050-00 1
W3 1/2-13x1-1/4 Hex Flange Screw Grade-5 1766-010-00 N/A 2
W3 3/8-16x1-1/4 Hex Flange Screw Grade-5 N/A 1757-007-00 2
W4 Gasket Incl. w/Ref. W5 Incl. w/Ref. W5 1
W5 Fill Cap 2124-000-00 2124-000-00 1
(includes Ref. Nos. W5, & W6)
W6 Discharge Plate 2131-000-00 3360-052-01 1
W7 1/2-13x1-1/4 Hex Flange Screw Grade-5 1766-010-00 N/A 2
W7 3/8-16x1-1/4 Hex Flange Screw Grade-5 N/A 1757-007-00 2
W8 1/8 Diameter x 3/8 Pin 2121-000-00 2121-000-00 2
W9 Check Valve (neoprene) / Asssembly Kit 3354-070-90 3360-070-90 2
(includes Ref. Nos. W9, W10, W11, & W12)
W10 Check Valve Weight Top Incl. w/Ref. W9 Incl. w/Ref. W9 1
W11 Check Valve Weight Bottom Incl. w/Ref. W9 Incl. w/Ref. W9 1
W12 1/4-20x1/2 Hex Head Cap Screw Incl. w/Ref. W9 Incl. w/Ref. W9 2

Specications Information and Repair Parts Manual 337 Series and 338 Series
3370-250-00 16 5/2022