Giant Triplex Ceramic Plunger Pump LP350 Troubleshooting guide

Models
LP350, LP400, LP450
Triplex Ceramic
Plunger Pump
Operating Instructions/
Repair and Service
Manual
Contents:
InstallationInstructions: page 2
PumpSpecifications: pages 3-5
Exploded View: page 6
Parts List/Kits/Torque Specs: page 7
Trouble Shooting Chart: page 8
Spare Parts List: page 8
Repair Instructions: page 9-11
Dimensions: back page
WarrantyInformation: back page
Updated 2/02

2
INSTALLATION INSTRUCTIONS
4. Use of a dampener is necessary to minimize
pulsation at drive elements, plumbing, connec-
tions, and other system areas. The use of a
dampener with Giant Industries, Inc. pumps is
optional, although recommended by Giant
Industries, Inc. to further reduce system pulsa-
tion. Dampeners can also reduce the severity of
pressure spikes that occur in systems using a
shut-off gun. A dampener must be positioned
downstreamfromtheunloader.
5. Crankshaft rotation on Giant Industries, Inc.
pumps should be made in the direction desig-
nated by the arrows on the pump crankcase.
Reverse rotation may be safely achieved by
following a few guidelines available upon
request from Giant Industries, Inc. Required
horsepower for system operation can be ob-
tained from the charts on pages 3-5.
6. Before beginning operation of your pumping
system, remember: Check that the crankcase
and seal areas have been properly lubricated per
recommended schedules. Do not run the pump
dry for extended periods of time. Cavitation will
result in severe damage. Always remember to
check that all plumbing valves are open and that
pumped media can flow freely to the inlet of the
pump.
IMPORTANTOPERATINGCONDITIONS
Failure to comply with any of these conditions invalidates the warranty.
2. Pump operation must not exceed rated
pressure, volume, or RPM. A pressure relief
device must be installed in the discharge of the
system.
3. Acids, alkalines, or abrasive fluids cannot be
pumped unless approval in writing is obtained
before operation from Giant Industries, Inc.
4. Run the pump dry approximately 10 seconds
to drain the water before exposure to freezing
temperatures.
1. Prior to initial operation, add oil to the
crankcase so that oil level is between the two
lines on the oil dipstick. DO NOT OVERFILL.
Use SAE 90 Industrial gear oil.
Crankcase oil should be changed after the
first 50 hours of operation, then at regular
intervals of 500 hours or less depending on
operatingconditions.
Installation of the Giant Industries, Inc.,
pump is not a complicated procedure, but
there are some basic steps common to all
pumps. The following information is to be
considered as a general outline for installa-
tion. If you have unique requirements, please
contact Giant Industries, Inc. or your local
distributor for assistance.
1. The pump should be installed flat on a base to
a maximum of a 15 degree angle of inclination
to ensure optimum lubrication.
2. The inlet to the pump should be sized for the
flow rate of the pump with no unnecessary
restrictions that can cause cavitation. Teflon
tape should be used to seal all joints. If pumps
are to be operated at temperatures in excess of
1400F, it is important to insure a positive head
to the pump to prevent cavitation.
3. The discharge plumbing from the pump
should be properly sized to the flow rate to
prevent line pressure loss to the work area. It is
essential to provide a safety bypass valve
between the pump and the work area to protect
the pump from pressure spikes in the event of a
blockage or the use of a shut-off gun.
Finally, remember that high pressure operation in a pump system has many advantages. But, if it is used
carelessly and without regard to its potential hazard, it can cause serious injury.

3
Specifications
Model LP350
Volume................................................................................................... Up to 22.6 GPM
Discharge Pressure ................................................................................. 2350 PSI
Inlet Pressure.......................................................................................... Up to 90 PSI
Maximum Crankshaft Speed................................................................... Up to 1000 RPM
Plunger Diameter.................................................................................... 30mm
Stroke..................................................................................................... 42mm
Crankcase Oil Capacity .......................................................................... 100 fl.oz.
Temperature of Pumped Fluids ............................................................... 140 oF @1000 RPM
............................................................................................................... 160 oF Up to 500 RPM
Inlet Port ................................................................................................ 1-1/4" BSP+
Discharge Port ........................................................................................ 1" BSP++
Shaft Mounting ...................................................................................... Either side
Shaft Rotation ............................................................................Top of pulley towards manifold
Weight.................................................................................................... 105 lbs.
Crankshaft Diameter............................................................................... 35mm
+
++
PULLEYINFORMATION
Pulley selection and pump speed are based on a 1725
RPM motor and "B" section belts. When selecting
desired GPM, allow for a ±5% tolerance on pumps
output due to variations in pulleys, belts and motors
amongmanufacturers.
1. Select GPM required, then select appropriate
motor and pump pulley from the same line.
2. Thedesiredpressureisachievedbyselectingthe
correct nozzle size that corresponds with the pump
GPM.
HORSEPOWER INFORMATION
Horsepower ratings shown are the power require-
ments for the pump. Gas engine power outputs
must be approximately twice the pump power
requirements shown above.
We recommend that a 1.1 service factor be specified
when selecting an electric motor as the power source.
To compute specific pump horsepower requirements,
use the following formula:
HP = (GPM x PSI) / 1440
LP350 PULLEY SELECTION AND HORSEPOWER
REQUIREMENTS
PUMP
PULLEY
MOTOR
PULLEY
RPM GPM 500 PSI 1000 PSI 2000 PSI 2300 PSI
12.75"
3.95"
500
11.3
3.9
7.8
15.7
18.0
12.75"
4.95"
640
14.5
5.0
10.0
20.1
23.1
12.75"
5.75"
750
16.9
5.9
11.8
23.5
27.1
12.75"
6.15"
805
18.2
6.3
12.6
25.3
29.0
12.75" 6.55" 865 19.5 6.8 13.6 27.1 31.2
12.75" 6.95" 940 21.2 7.4 14.7 29.5 33.9
12.75" 7.50" 1000 22.6 7.8 15.7 31.4 36.1

4
Specifications
Model LP400
Volume................................................................................................... Up to 15.1 GPM
Discharge Pressure ................................................................................. 3600 PSI
Inlet Pressure.......................................................................................... Up to 90 PSI
Maximum Crankshaft Speed................................................................... Up to 1000 RPM
Plunger Diameter.................................................................................... 24mm
Stroke..................................................................................................... 42mm
Crankcase Oil Capacity .......................................................................... 100 fl.oz.
Temperature of Pumped Fluids ............................................................... 140 oF @1000 RPM
............................................................................................................... 160 oF Up to 500 RPM
Inlet Port ................................................................................................ 1-1/4" BSP
Discharge Port ........................................................................................ 1" BSP
Shaft Mounting....................................................................................... Either side
Shaft Rotation ............................................................................Top of pulley towards manifold
Weight.................................................................................................... 105 lbs.
Crankshaft Diameter............................................................................... 35mm
PULLEYINFORMATION
Pulley selection and pump speed are based on a 1725
RPM motor and "B" section belts. When selecting
desired GPM, allow for a ±5% tolerance on pumps
output due to variations in pulleys, belts and motors
amongmanufacturers.
1. Select GPM required, then select appropriate
motor and pump pulley from the same line.
2. Thedesiredpressureisachievedbyselectingthe
correct nozzle size that corresponds with the pump
GPM.
HORSEPOWER INFORMATION
Horsepower ratings shown are the power require-
ments for the pump. Gas engine power outputs
must be approximately twice the pump power
requirements shown above.
We recommend that a 1.1 service factor be specified
when selecting an electric motor as the power source.
To compute specific pump horsepower requirements,
use the following formula:
HP = (GPM x PSI) / 1440
LP400 PULLEY SELECTION AND HORSEPOWER
REQUIREMENTS
PUMP
PULLEY
MOTOR
PULLEY
RPM GPM
2000 PSI
2500 PSI 3000 PSI 3600 PSI
12.75"
3.95"
500
7.5
10.5
13.1
15.7
18.8
12.75"
4.95"
640
9.6
13.4
16.7
20.1
24.1
12.75"
5.75"
750
11.3
15.7
19.6
23.5
28.2
12.75"
6.15"
805
12.1
16.8
21.0
25.3
30.3
12.75" 6.55" 865 13.0 18.1 22.6 27.1 32.6
12.75" 6.95" 940 14.2 19.7 24.6 29.5 35.4
12.75" 7.50" 1000 15.1 20.9 26.1 31.4 37.6

5
Specifications
Model LP450
Volume................................................................................................... Up to 19.7 GPM
Discharge Pressure ................................................................................. 2600 PSI
Inlet Pressure.......................................................................................... Up to 90 PSI
Maximum Crankshaft Speed................................................................... Up to 1000 RPM
Plunger Diameter.................................................................................... 28mm
Stroke..................................................................................................... 42mm
Crankcase Oil Capacity .......................................................................... 100 fl.oz.
Temperature of Pumped Fluids ............................................................... 140 oF @1000 RPM
............................................................................................................... 160 oF Up to 500 RPM
Inlet Port ................................................................................................ 1-1/4" BSP
Discharge Port ........................................................................................ 1" BSP
Shaft Mounting....................................................................................... Either side
Shaft Rotation.............................................................................Top of pulley towards manifold
Weight.................................................................................................... 105 lbs.
Crankshaft Diameter............................................................................... 35mm
PULLEYINFORMATION
Pulley selection and pump speed are based on a 1725
RPM motor and "B" section belts. When selecting
desired GPM, allow for a ±5% tolerance on pumps
output due to variations in pulleys, belts and motors
amongmanufacturers.
1. Select GPM required, then select appropriate
motor and pump pulley from the same line.
2. Thedesiredpressureisachievedbyselectingthe
correct nozzle size that corresponds with the pump
GPM.
HORSEPOWER INFORMATION
Horsepower ratings shown are the power require-
ments for the pump. Gas engine power outputs
must be approximately twice the pump power
requirements shown above.
We recommend that a 1.1 service factor be specified
when selecting an electric motor as the power source.
To compute specific pump horsepower requirements,
use the following formula:
HP = (GPM x PSI) / 1440
LP450 PULLEY SELECTION AND HORSEPOWER
REQUIREMENTS
PUMP
PULLEY
MOTOR
PULLEY
RPM GPM
1000 PSI
1500 PSI 2000 PSI 2600 PSI
12.75"
3.95"
500
9.8
6.8
10.3
13.7
17.8
12.75"
4.95"
640
12.6
8.7
13.1
17.5
22.7
12.75"
5.75"
750
14.8
10.3
15.4
20.5
26.7
12.75"
6.15"
805
15.8
11.0
16.5
22.0
28.6
12.75" 6.55" 865 17.0 11.8 17.7 23.6 30.7
12.75" 6.95" 940 18.5 12.8 19.3 25.7 33.4
12.75" 7.50" 1000 19.7 13.7 20.5 27.3 35.5

6
LP350, LP400, LP450 - EXPLODED VIEW

7
ITEM # PART # DESCRIPTION QTY
107759 Crankcase 1
213000 Oil filler plug assy. 1
406085 CrankcaseCover 1
507104 O-ring, Crankcase cover 1
607186 Oil Sightglass with Gasket 1
806086 OilDipstick 1
901009 O-Ring,Dipstick 1
10 01010 CylinderScrew 4
11 01011 Spring Ring 5
12 07109 Plug 1
13 07182 Gasket 1
14 07111 Bearing Cover 2
15 07112 Radial Shaft Seal 2
16 07113 O-Ring 2
17 07114 Hexagon Screw 8
20 07116 Taper Roller Bearing 2
20A 07117 FittingDisc 1-3
20B 13001 Fitting Disc (May not be present) 1-3
21 07118 ShaftProtector 1
22 13242 Crankshaft 1
23 13243 WoodruffKey 1
24 13340 Connecting Rod Assy. 3
24A 13277 Inner Hexagon Screw 6
24B 13278 SpringWasher 6
25 13244 Crosshead / Plunger Assy. 3
28 13232 CrossheadPin 3
29A 07256 Centeringsleeve 3
29B 13046 PlungerPipe(LP400) 3
29B 13005 PlungerPipe(LP450) 3
29B 07261 PlungerPipe(LP350) 3
29C 13007 Tensioning Screw 3
29D 07258 CopperRing 3
30 07779 O-Ring 3
31 07133 Oil Seal 3
35 13392 SealSleeve(LP400) 3
ITEM # PART # DESCRIPTION QTY
35 06650 SealSleeve(LP350,LP450) 3
37 13393 SealCase(LP400) 3
37 06651 SealCase(LP350/LP450) 3
38 07140 O-Ring(LP400) 3
38 07700 O-Ring(LP350/LP450) 6
38A 12055 O-Ring(LP400Only) 3
39 07271 PressureRing(LP350) 3
39 13016 PressureRing(LP400) 3
39 13013 PressureRing(LP450) 3
40 13016 V-Sleeve(LP350) 6
40 06083 V-Sleeve(LP400) 6
40 13015 V-Sleeve(LP450) 6
41 07273 SupportRing(LP350) 3
41 13367 SupportRing(LP400) 3
41 06652 SupportRing(LP450) 3
42 07338 PressureSpring(LP400) 3
42 14084 PressureSpring(LP350/LP450) 3
43 13018 Valve Casing 1
44A 07150 O-Ring 9
44B 06266 Support Ring 3
45 06078 CompressionSpring 3
46 07060 Valve Assy. 6
46A 07064 Valve Seat 6
46B 07063 Valve Plate 6
46C 07062 Valve Spring 6
46D 07066 SpacerPipe 6
48 07156 Plug 3
49 07754 Stud bolt 8
49A 07158 Hexagon Nut 8
49B 07159 Disc 8
50 07423 Plug, 1/4" BSP 1
50A 07161 CopperRing 1
52 13020 DiscforCrankshaft 1
53 06607 Hexagon Screw 1
LP350, LP400 & LP450 PARTS LIST
TORQUE SPECIFICATIONS
Position Description TorqueAmount
24 Connecting Rod 264 in.-lbs.
29C Tensioning Screw 33 ft.-lbs.
49A Hexagon Nut 59 ft.-lbs.
LP350,LP400&LP450KITS
PackingKit,LP350 #09233
(prior to 2/97)
Item Part # Description Qty
38 7140 O-ring 3
38A 13012 O-ring 3
40 13016 V-sleeve 6
41 7150 O-ring 3
PackingKit,LP400 #09309
(prior to 2/97)
Item Part # Description Qty
38 07140 O-ring 3
38A 13012 O-ring 3
40 13049 V-sleeve 3
40A 13050 Support-ring 3
PackingKitLP450 #09234
(prior to 2/97)
Item Part # Description Qty
38 07140 O-ring 3
38A 12055 O-ring 3
40 13015 V-Sleeve 6
41 06652 O-ring 3
PackingKit,LP350 #09546
(after2/97)
Item Part # Description Qty
38 07700 O-Ring 6
40 13016 V-Sleeve 6
PackingKitLP400 #09548
(afterto 2/97)
Item Part # Description Qty
38 07140 O-ring 3
38A 12055 O-ring 3
40 06083 V-sleeve 6
PackingKitLP450 #09549
(afterto 2/97)
Item Part # Description Qty
38 07700 O-ring 6
40 13015 V-Sleeve 6
Valve Kit #09196
Item Part # Description Qty
44A 07150 O-Ring 6
44B 06266 Support Ring 3
46A 7064 Valve seat 1
46B 7063 Valve plate 1
46C 7062 Valve spring 1
Pumps Manufactured Prior to 2/97 PumpsManufactured After2/97

8
PUMP SYSTEM MALFUNCTION
MALFUNCTION CAUSE REMEDY
The Pressure and/ Worn packing seals Replace packing seals
or the Delivery Broken valve spring Replace spring
Drops Belt slippage Tighten or Replace belt
Worn or Damaged nozzle Replace nozzle
Fouled discharge valve Clean valve assembly
Fouled inlet strainer Clean strainer
Worn or Damaged hose Repair/Replace hose
Worn or Plugged relief valve on pump Clean, Reset, and Replace worn parts
Cavitation Check suction lines on inlet of
pump for restrictions
Unloader Check for proper operation
Water in crankcase High humidity Reduce oil change interval
Worn seals Replace seals
Noisy Operation Worn bearings Replace bearings, Refill crankcase
oil with recommended lubricant
Cavitation Check inlet lines for restrictions
and/or proper sizing
Rough/Pulsating Worn packing Replace packing
Operation with Inlet restriction Check system for stoppage, air
Pressure Drop leaks, correctly sized inlet
plumbing to pump
Accumulator pressure Recharge/Replace accumulator
Unloader Check for proper operation
Cavitation Check inlet lines for restrictions
and/or proper size
Pump Pressure as Restricted discharge plumbing Re-size discharge plumbing to Drop at
gun flow rate of pump
Rated, Pressure
Excessive Worn plungers Replace plungers
Leakage Worn packing/seals Adjust or Replace packing seals
Excessive vacuum Reduce suction vacuum
Cracked plungers Replace plungers
Inlet pressure too high Reduce inlet pressure
High Crankcase Wrong Grade of oil Giant oil is recommended
Temperature Improper amount of oil in crankcase Adjust oil level to proper amount
Preventative Maintenance Check-List & Recommended Spare Parts List
Check Daily Weekly 50hrs Every Every Every
500 hrs 1500 hrs 3000 hrs
Oil Level/Quality X
Oil Leaks X
Water Leaks X
Belts, Pulley X
Plumbing X
RecommendedSpareParts
Oil Change (1 Gallon) p/n 1154 XX
Seal Spare Parts (1 kit/pump) X
(See page 7 for kit list)
Oil Seal Kit (1 kit/pump) X
(See page 7 for kit lit)
Valve Spare Parts (1 kit/pump) X
(See page 7 for kit list)

9
REPAIR INSTRUCTION - LP350, LP400, LP450
TO CHECK VALVES
4) Inspect valve seats (46A) and valve plates (46B) for damage
and replace if needed. Check valve casing (43) surfaces for
damage. Replace o-rings (44A) and reinstall valve assemblies
(46) into valve casing. (Lubricate o-rings before installation.)
5) Replace tension plugs (48)
and tighten them securely.
46D 46C 46B 46A 44A
1) With a 30mm wrench
remove the three (3)
tension plugs (48) from top
of valve casing (43).
2) Remove discharge and inlet
valve assemblies (46) by
pulling them upwards out of
the valve casing (43). It
maybe necessary to use a
slide hammer tool.
3) Withthevalveassembly(46)
pointeddown,placeadowel
rodthroughthetop ofspacer
pipe (46D). Hold assembly
inhand and tap endofdowel
sharply with mallet until as-
semblybreaksfree.
6) Remove the eight (8)
manifold nuts and washers
(49A,B) using a 19mm
wrench and pull off valve
casing (43).
7) If needed, tap valve casing
with a rubber mallet to re-
move it.
8) Using two flat screw drivers,
pry seal sleeve (35) out of
crankcase guides.
SEALAND PLUNGER REPLACEMENT

10
9) Remove seal case (37) from
seal sleeve (35). 10) Check plunger surface (25
and 29B) for wear and pit-
ting. If none is found, pro-
ceed to step twelve.
11) Ifplunger(29B)isworn,re-
move tension screw (29C)
with a 17mm wrench. Clean
tension screw with wire
brush to remove any old
locktite. Discard copper gas-
ket (29D) and replace with
new. Clean the front surface
of plunger/ crosshead as-
sembly (25). Install new
plunger (29B) onto plunger/
crosshead assembly. Put
some locktite on both sur-
faces of copper gasket and
tension screw threads. Se-
cure plunger in place with
tension screw and gasket
and tighten to 33 ft.-lbs.
REPAIR INSTRUCTION - LP350, LP400, LP450
12) Remove v-sleeves (40) and support ring (41) for seal case (37)
and replace with new elastomers. Lubricate parts before
reinstalling into seal sleeve. Replace seal sleeve/seal case
assembly (35/37) into the valve casing (43).
35 39 40 (2) 41 42 38 38A 37 38
(LP400 only)
13) Placeentiremanifoldassem-
bly sleeve assembly over the
studs (49) and push firmly
untilseatedagainstthecrank-
case (1).
14) Replace nuts and washers
(49A,B) and tighten to59ft.-lbs.
in the pattern as shown to the
right. 6427
81 3 5

11
DISASSEMBLY OF CRANKCASE
1) Remove valve casing (43) and plunger pipe (29B), drain oil.
2) Screw off gear cover (4) and bearing cover (14).
3) Remove connecting rod screws (24) and push the front of connecting rod forward as far as possible. Remove
back halves of connecting rods, note which position from which they came from.
4) Turning the crankshaft slightly, carefully hit on side of crankshaft (22) with a rubber mallet until crankshaft is
loose.
CAUTION:Donotbendtheconnectingrodshafts.Checkcranshaftandconnectingrodsurfaces,shaft
seals and taper roller bearings.
REASSEMBLY
5) Using a soft tool, press in the outer bearing ring until the outer edge lines up with the outer edge of the
bearing hole (1).
6) Remove the bearing cover (14) together with the shaft seal (15) and o-ring (16). Fit crankshaft through
bearing hole on the opposite side.
7) Press in outer bearing (20) inwards with the bearing cover (14). Make sure that the crankshaft is in a vertical
position and turn it slowly so that the taper rollers of the bearings touch the edge of outer bearing ring.
8) Adjust axial bearing clearance to at least .004” and maximum at .006” by placing fitting discs (20A and/or
20B) under the bearing cover (14).
CAUTION: After assembly has been completed, the crankshaft should turn easily and with very
little clearance.
9) Bolt connecting rod halves together making sure they are replaced in the same position from which they
came. Tighten connecting rod screws to 264 in.-lbs.
REPAIR INSTRUCTIONS - LP350, LP400, LP450

GIANT INDUSTRIES LIMITED WARRANTY
Giant Industries, Inc. pumps and accessories are warranted by the manufacturer to be free from
defects in workmanship and material as follows:
1. Forportablepressurewashersandcarwashapplications,thedischargemanifoldswill
neverfail,period. Iftheyeverfail, wewillreplacethem freeofcharge.Our otherpump
parts, used in portable pressure washers and in car wash applications, are warranted
for five years from the date of shipment for all pumps used in NON-SALINE, clean
water applications.
2. One (1) year from the date of shipment for all other Giant industrial and consumer
pumps.
3. Six (6) months from the date of shipment for all rebuilt pumps.
4. Ninety (90) days from the date of shipment for all Giant accessories.
Thiswarrantyislimitedtorepairorreplacementofpumpsandaccessoriesofwhichthe manufacturer’s
evaluation shows were defective at the time of shipment by the manufacturer. The following items
are NOT covered or will void the warranty:
1. Defects caused by negligence or fault of the buyer or third party.
2. Normal wear and tear to standard wear parts.
3. Use of repair parts other than those manufactured or authorized by Giant.
4. Improper use of the product as a component part.
5. Changes or modifications made by the customer or third party.
6. The operation of pumps and or accessories exceeding the specifications set forth
in the Operations Manuals provided by Giant Industries, Inc.
Liability under this warranty is on all non-wear parts and limited to the replacement or repair of those
products returned freight prepaid to Giant Industries which are deemed to be defective due to
workmanshiporfailureofmaterial. AReturnedGoodsAuthorization(R.G.A.)numberandcompleted
warranty evaluation form is required prior to the return to Giant Industries of all products under
warranty consideration. Call (419)-531-4600 or fax [phone] to obtain an R.G.A. number.
Repairorreplacementofdefectiveproductsasprovidedisthesoleandexclusiveremedyprovided
hereunderandtheMANUFACTURERSHALLNOTBELIABLEFORFURTHERLOSS,DAMAGES,
OREXPENSES,INCLUDINGINCIDENTALANDCONSEQUENTIALDAMAGESDIRECTLYOR
INDIRECTLYARISINGFROMTHESALEORUSEOFTHISPRODUCT.
THELIMITEDWARRANTYSETFORTHHEREINISINLIEUOFALLOTHERWARRANTIESOR
REPRESENTATION,EXPRESSORIMPLIED,INCLUDING WITHOUT LIMITATION ANYWAR-
RANTIESORMERCHANTABILITYORFITNESSFORAPARTICULARPURPOSEANDALLSUCH
WARRANTIESAREHEREBYDISCLAIMEDANDEXCLUDEDBYTHEMANUFACTURER.
GIANT INDUSTRIES, INC. 900 N. Westwood Ave., P.O. Box 3187, Toledo, Ohio 43607
Phone: [phone] FAX [phone], www.giantpumps.com
 Copyright 2002 Giant Industries, Inc. 2/02 LP350.PM6
LP350, LP400 & LP450 DIMENSIONS (inches)