Yamaha PW3028A User manual

PRESSURE WASHER
SERVICE MANUAL
PW3028A
PW3028B
LIT-19616-PW-30 7DH-F819P-10

2
TABLE OF CONTENTS
GENERAL INFORMATION
 GeneralCheckandSetup ..................................3

 AccessoryChecklist ...........................................4

 GlossaryofTerms...............................................4

 RecommendedServiceTools.............................5

 QuickStartGuideandCommon
  CustomerErrors .................................................6
TROUBLESHOOTING
 GeneralTroubleshooting.....................................7
 TroubleshootingChart-AllPumpTypes ........ 8-9
 DiagnosisandMaintenance ....................... 10-11
 AvoidCavitationDamage .................................12
 NotWarrantedExamples..................................13
SERVICING
 TriplexPlungerPumps......................................14
 PressureWasherSystem..................................14
 Servicing..................................................... 15-24
   ManifoldRemoval..........................................15
   ValveAssemblyRemoval ..............................15
   SoapInjectorAssemblyRemoval .................15
   UnloaderRemoval.........................................15
   PlungerChamberRemoval ...........................15
   CeramicPlungerRemoval.............................16
   ValveAssemblyReplacement .......................16
   SoapInjectorAssemblyReplacement ..........16
   UnloaderReplacement..................................16
   CeramicPlungerReplacement......................17
   PlungerChamberReplacement ....................17
   ManifoldReplacement ..................................17
   CrankcaseSealandO-RingReplacement....17
   IdleDownAdjustment ...................................21
PUMP SPECIFICATIONS
 CATPumpRepairKits ................................ 22-23
 PumpReplacement ..........................................24
 PumpPressureSettingProcedure ...................25
 CATPumpHighPressureSettingProcedure ...26
 GeneralSpecifications................................ 27-28

3
GENERAL CHECK AND SETUP
Always refer to the operator’s manual delivered with the pressure washer for general checks and setup. Initial
observationsshouldbetakenwhenthepressurewasherisreceivedatyourservicecenter.Inordertocreatea
properrecordofrepairs,thefollowingshouldbecheckedbeforebeginningservice:
SAFETY AND SERVICE BULLETIN CHECK:
Safety
Allpotentialhazardousconditions,includingbutnotlimitedto,crackedfuellines,crackedframesand/orelectrical
issues,shouldbecheckedandrecommendedforrepairifoutofwarranty.Outofwarrantyconcernsshouldalso
benotedandconfirmedifcustomerwillaccepttherepair.
Service Bulletin
Anyservicebulletinsshouldbecheckedanddefectsdescribedintheservicebulletincorrected.
ENGINE LUBRICANT:
Toaddorcheckrefertotheenginemanufacturer’sdocumentationformoreinformation:

 Placepressurewasheronaflat,levelsurface.

 Unscrewtheoilcap/dipstickbyturningcounter-clockwise.

 Using4-strokeenginelubricant(SAE30orSAE10W30),addengineoiluntilthefluidlevelrisestotheupper
portionofthehatchedareaonthedipstick.

 Replacetheoilcap/dipstickandsecurelytighten.
PUMP LUBRICANT:

 Allpumpsshipwithoilalreadyinsidedirectfromthefactory.Thereisnoneedtoaddoilunlessthisisapump
maintenanceissue.

 Makeavisualinspectionofthepressurewasher’spump.

NOTE: Beforecommencingwithservice,shutoffdriveandturnoffwatersupplytopump.Relievealldis-
chargelinepressurebytriggeringwandoropeningvalvedischargeline.Afterservicingiscompleted,turn
onwatersupplytopump,startdrive,resetpressureregulatingdeviceandsecondaryvalve,readsystem
pressureonthegaugeatthepumphead.Checkforanyleaks,vibrationorpressurefluctuationsandresume
operation.
ACCESSORIES:
Avisualcheckofalldeliveredaccessoriesshouldbemadealsoduringinitialreceipt.Damagecausedbymisuse,
neglect,accident,abuse,improperhandling,freezing,normalwearandtearornon-compliancewithoperator’s
manualarenotcoveredaspreviouslyindicated.Itemsliketriggerwands,spraylances,nozzlesorhighpressure
hoseswithfailuresrightoutofthebox,shouldbereplacedunderwarrantybeforedeliveringbacktothecustomer.

4
ACCESSORY CHECKLIST
SPRAY WAND:
 Determinewheretheleakageorfailureoccurs.
 Pressurizeaccessorytotheratedpressureandcyclethetriggerlever.Ifwandleakswhilenotactivatingthe
triggerlever,replacewand.CheckO-ringsandreplaceasneeded.
SPRAY WANDS/LANCES:
 Determinewheretheleakageorfailureoccurs.
 Insertnozzlesandspraytoratedpressure.Ifanewnozzlegetsstuckinthecoupler/fittingreplacelance
assembly.
HIGH PRESSURE HOSE:
 Determinewheretheleakageorfailureoccurs.
 CheckO-ringsandconnections.
NOZZLES:
Spraytipsizeisaveryimportantfactorofproperpressurewasherperformance.Usingatipthatissizedtoosmall
willallowoverpressurizationofthepumpandcomponents.YoumustknowyouroutputGPMandyourdesired
outputPSItoproperlyselectaspraytipsize.
 Quick-ConnectNozzles-Spraytipsareavailableinvarioussprayangles/degrees;0,15,25,and40.
 TurboNozzles–Theseincreasecleaningefficiencyasmuchas200%comparedtoa25degreeflatfannozzle.
The0degreerotationcreatesacleaningandtearingaction.
 SoapBlaster–Thenozzlecanbeeasilyadjustedforlongrangeorshortrangecleaning.
NOZZLE MAINTENANCE: (ALL PRESSURE WASHERS)
Excessivepumppressure,apulsingsensationfeltwhilesqueezingthetrigger,maybetheresultofacloggedor
dirtynozzle.Checkthenozzleusingthefollowingprocedures.
 Turnoffthepressurewasherandshutoffthewatersupply.Pulltriggertoreleasewaterpressure.
 Removethenozzlefromthespraylance.
 Usingastraightenedpaperclipornozzlecleaningtool,freeanyforeignmaterialscloggingorrestrictingthe
nozzle.
 Flushanydebrisoutofnozzle.
GLOSSARY OF TERMS
GPM
GallonsPerMinute
HP
HighPressure
LP
LowPressure
NP
NozzlePressure
PSI
PoundsPerSquareInch

5
RECOMMENDED SERVICE TOOLS
5000
1000
50
0
0
100 150 200
250
300
350
2000
3000
4000
BAR
100xkPa
psi
TITE
242
RPM METER
HEX KEY
(5 mm AND 10 mm)
PRESSURE
GAUGE
REVERSE PLIERS
WRENCH
(19 mm AND 24 mm)
3/8 in. NPT
QUICK CONNECTS
0º NOZZLE
PICKS
SEAL
INSTALLATION TOOL
RUBBER MALLET
SAFETY GOGGLES
Silicone
Grease
Silicone
Grease
NEEDLE NOSE
PLIERS
FLAT HEAD
SCREWDRIVER
PHILLIPS HEAD
SCREWDRIVER Fig.1
MENU
LOCK
99.999
RPM
MONARCH
PT99

6
QUICK START GUIDE AND COMMON CUTOMER ERRORS
STARTING THE UNIT (COLD START)
 1. Addfuel.Addfuelstabilizereverytimeyoufuelthemachine.
 2. TurnthefuelvalvetoON.
 3. PutchokeleverinON(START)position.
 4. PutengineswitchinONposition.
 5. Pullrecoilstartertostart.Iftheenginedoesnotstartaftereachpulloftherecoilstarter,squeezethetrigger
torelievewaterpressurebeforeattemptingtostarttheengineagain.
 6. Allowenginetorunforseveralseconds,thenmovechoketoOFF(RUN)position.
RESTARTING THE UNIT (HOT RESTART)
 1. Squeezethetriggertoreliefwaterpressure.Unitwillnotstartuntilthisisdone.
 2. Pullrecoilstartertostart.
  IfTheEngineDoesNotStart:
  * Checkforenoughfuel.
  * Mayneedtoadjustchokeposition.
  * Trystartingagain.
940873007-04
NOTICE
DONOT USE FUEL
CONTAINING MORE
THAN 10% ETHANOL;
IT IS A VIOLATION
OF U.S. FEDERAL LAW,
WILL DAMAGE YOUR
PRODUCT, AND VOID
THE WARRANTY.
E
T
H
A
N
O
L
F
R
E
E
DO NOT USE E15 OR E85 FUEL IN THIS UNIT.
IT IS A VIOLATION OF FEDERAL LAW AND WILL
DAMAGE THE UNIT AND VOID YOUR WARRANTY.
WARNING! Never use bleach or
solvent-based detergent.
•Will damage your pump
•Will void your warranty
•Will damage plants/shrubs
Completely uncoil garden hose or
remove completely from reel to
prevent kinks.
Completely uncoil garden hose or
remove completely from reel to
prevent kinks.
This is a 4-cycle engine. Do not mix
fuel and oil together.
Add fuel stabilizer every time you
fuel the machine.
Turn water faucet on fully.
Make sure there are no leaks.
DO NOT OVERTILT THE UNIT!
Fig.2

7
Findthesectionthatdefinesthemalfunctionofthepump.Turntothatsection'soverviewpageandidentifythe
specificproblem.Thengotothesolutionspageforthatspecificproblem.Ifyoudon'tknowwhattheproblemis,
workyourwaythroughtheproblemslisteduntilyoufindandcorrecttheproblem.
A.WATERSUPPLY
 Checkfaucet.2.5gpmisrequired.
 Outsidediameterofhoseshouldbe¾”or5/8”
 Maximumlengthofhoseshouldbe50’.
 Theinletwaterpressureshouldnotexceed90psi.
 Hoseshouldnotbekinkedordamaged.
B.NOZZLE
Checkfunctionandsettingoforiginalnozzlebyusinganin-housenozzle.Ifpumpfunctionsproperlywithin-house
nozzlebutmalfunctionswithoriginalnozzle,replacenozzle.
C.WaterInletFilter
Removefilterwithpairofvalvepliers.
 Cleanfilter.
 Replacefilterifitistorn,bentormissing.
 Reinstallfilter.
NOTE: Ifwaterinletfilterismissingordamaged,furtherdamagemayhaveoccurredinsidethepump.
D.DETERGENTINJECTOR
 a.Detergentnotdrawing
 Checkthatnozzleisinlow/chemicalposition.
 Checkthatmeteringvalveonpickupfilterisopen.
 Checkpickupfilterforclog.
 Checkdetergenttubeforholesandkinks.
 Removetubefromnipple
 Removedetergentnon-returncheckvalve.
 Inspectnon-returncheckvalveforclogs.
NOTE:Leavingdetergentinpumpwillcauseballtostick.
 Reinstallnon-returncheckvalve,nipple,meteringknobandhose.
 b.NozzleInsert
 Removenozzleinsertwithascrewdriver.
 Pulloutnozzleinsert.
 Checknozzleforwearanddamage.
 Checkthatopeningthroughnozzleisnotclogged.Clearopeningifnecessary.
E.BYPASSVALVE
 Unscrewpressurecontrolnut
 Pulloutbypassvalve.
 Inspectbypassvalvefordamageandlubrication.Inadequatelubricationwillcausevalvetohangup.
 InspectO-ringsfornicksorcuts.Replaceifnecessary.
 GreaseonlylargeO-ringswithsiliconegrease.
 Replacebypassvalveifnecessary.
F.THERMALRELIEFVALVE
 Unscrewthesafetyreliefvalvescrewcap.
 Checkforwearorpitting.
 Replacevalveifnecessary.
 Turnthermalreliefvalveholedownward.
GENERAL TROUBLESHOOTING

8
TROUBLESHOOTING CHART - ALL PUMP TYPES
SYMPTOMS CAUSES REMEDIES
Detergentfailstomixwithspray Detergent injection hose is not
properlysubmerged
Highpressurenozzleattached
Insert injection hose into detergent
containerordetergentbottle
Useblackorbluesoapnozzle.
Pumpdoesn’tproducepressure
LowPressure
Lowpressurenozzleinstalled
Inadequatewatersupply
Triggerhandleorspraywandleaks
Nozzleisclogged
Airinline
Inletfilterclogged
Pressurereliefvalvestuck;partially
pluggedorimproperlyadjustedvalve
seatworn.
Replacewithhighpressurenozzle
Provideadequatewaterflow
Check connections and/or replace
triggerhandleorspraywand
Cleannozzle
Squeezetriggerontriggerhandleto
removeairfromline
Removefilter,rinsecleanandreinstall
Clean, adjust relief valve; check
for worn and dirty valve seats. Kit
available.
Machinedoesn’treachhighpressure Diameterofgardenhoseistoosmall
Watersupplyisrestricted
Notenoughinletwaterpressure
Wrongnozzleisattached
Replacewith5/8in.or3/4in.IDhose
Checkgardenhoseforkinks,leaks
andblockages
Open water source fully, minimum
35PSI.
Attachthehighpressurenozzle
Irregularpressurevibration Pumpsuckingair
Nozzleinadequateorworn
Worn,dirty/blockedvalves
Checkthatthereisnowaterleaking
asitentersthepump
Cleanand/orreplacenozzle
Replacecheckvalves

9
SYMPTOMS CAUSES REMEDIES
Irregularpumppressure Pumpsuckingair
Blockednozzle
Airinpump
Waterinletfilterblocked
Inadequatewatersupply
Worn,dirty/blockedvalves
Wornpacking
Checkthatthereisnowaterleaking
asitentersthepump
Cleanand/orreplacenozzle
Pull the trigger to release air in
system
Cleanfilter
Make sure tap is completely open
and/or connect to a tap that has
adequateflowratetoatleast35PSI
Replacecheckvalve
Installnewsealkit
Pressuredrop Wornnozzle
Dirtyorblockedvalves
Wornpacking
LowWaterPressure
Replacethenozzle
Replacecheckvalves
Installnewsealkit
Check for proper pressure, should
be35to80PSI
Excessivenoise Pumpsuckingair
Blockedsuction
Watertemperatureistoohot
Worn,dirty/blockedvalves
Wornbearing
Valve stuck open or shut, or not
openingenough.
Checkthatthereisnowaterleaking
asitentersthepump
Inspectfilterandinletsupply
Max water temp must not exceed
104 F
Replacecheckvalves
Replacebearing
Replacebadvalve
Waterleakfromhead Wornpacking Installnewsealkit
TROUBLESHOOTING CHART - ALL PUMP TYPES

10
DIAGNOSIS AND MAINTENANCE
Oneofthemostimportantstepsinahighpressuresystemistoestablisharegularmaintenanceprogram.This
willvaryslightlywitheachsystemandisdeterminedbyvariouselementssuchasthedutycycle,theliquidbeing
pumped,theactualspecificationsvsratedspecificationsofthepump,theambientconditions,theinletconditions
andtheaccessoriesinthesystem.Acarefulreviewofthenecessaryinletconditionsandprotectiondevicesrequired
beforethesystemisinstalledandeliminatemanypotentialproblems.
PROBLEM PROBABLE CAUSE SOLUTION
Low pressure Wornnozzle.
Airleakinletplumbing.
Pressuregaugeinoperativeornot
registeringaccurately.
Reliefvalvestuck,partiallypluggedor
improperlyadjusted.
Inletsuctionstrainer(filter)cloggedor
improperlysized.
Abrasivesinpumpedliquid.
Leakydischargehose.
Inadequatewatersupply.
Severecavitation.
WornSeals.
Wornordirtyinlet/dischargevalves.
Replacewithproperlysizednozzle.
Tightenfittingsandhoses.UsePTFE
liquidortape.
Checkwithnewgauge.Replaceworn
ordamagedgauge.
Clean/adjustreliefvalve.Replace
worn/seatsando-rings.
Cleanfilter.Useadequatesizefilter.
Checkmorefrequently.
Installproperfilter.
Replacedischargehosewithproper
ratingforsystem.
Inadequatewatersupply,minimum
35PSIandhosesize3/4”-5/8”.
Checkinletconditions
Installnewsealkit.Increase
frequencyofservice.
Cleaninlet/dischargevalvesorinstall
newvalvekit.
Pulsation Inadequatewatersupply.
Foreignmaterialtrappedininlet/
dischargevalves.
Inadequatewatersupply,minimum
35PSIandhosesize3/4”-5/8”.
Cleaninlet/dischargevalvesorinstall
newvalvekit.
Water leak
Underthemanifold.
Intothecrankcase.
WornV-Packing,Hi-Pressureor
Lo-PressureSeals
Wornadaptero-rings.
Excessiveweartoseals.
Installnewsealkit.Increase
frequencyofservice.
Installnewo-rings.
Installnewsealkit.Increase
frequencyofservice.
Kocking noise
Inletsupply.
Bearing.
Inadequatewatersupply.
Brokenorwornbearing.
Inadequatewatersupply,minimum
35PSIandhosesize3/4”-5/8”.
Replacebearing.

11
DIAGNOSIS AND MAINTENANCE
Oil leak
Crankcaseoilseals.
Crankshaftoilseals
ando-rings.
Drainplug.
Bubblegauge.
Bearingcover.
Fillercap.
Replacingoil.
Worncrankcaseoilseals.
Worncrankshaftoilsealsoro-ringson
bearingcover.
Loosedrainplugorworndrainplug
o-ring.
Loosebubblegaugeorwornbubble
gaugegasket.
Loosebearingcoverorwornbearing
covero-ring.
Loosefillercaporexcessiveoilin
crankcase.
Loosenfillercap
Replacecrankcaseoilseals.
Removebearingcoverandreplace
o-ringsand/oroilseals.
Tightendrainplugorreplaceo-ring.
Tightenbubblegaugeorreplace
gasket.
Tightenbearingcoverorreplace
o-ring.
Tightenfillercap.Fillcrankcaseto
specifiedcapacity.
FillwithCAToiltoreddotonthe
bubblegauge.
Pump runs extremely
rough
Inletconditions.
Pumpvalves.
Pumpseals.
Restrictedinletorairenteringtheinlet
plumbing.
Stuckinlet/dischargevalves.
LeakingV-Packing,Hi-Pressureor
Lo-Pressureseals.
Correctinletsizedplumbing.Check
forairtightseal.
Cleanoutforeignmaterialorinstall
newvalvekit.
Installnewsealit.Increasefrequency
ofservice.
Premature seal failure
Scoredplungers.
Overpressuretoinletmanifold.
Abrasivematerialinthewaterbeing
pumped.
Excessivepressureand/ortemprature
ofpumpedwater
Runningpumpdry.
Starvingpumpofadequatewater.
Erodedmanifold.
Replaceplungers.
Reduceinletpressureper
specifications.
Installproperfiltrationatpumpinlet
andcleanregularly.
Checkpressureandinletwater
temperature.
DONOTRUNPUMPWITHOUT
WATER.
Inadequatewatersupply,minimum
35PSIandhosesize3/4”-5/8”.
Replacemanifold.Checkwater
compatibilty.

12
Fig.3
AVOID CAVITATION DAMAGE
Oneorseveraloftheconditionsshowninthechartbelowmaycontributetocavitationinasystemresultingin
prematurewear,systemdowntimeandunnecessaryoperatingcosts.
CONDITION SOLUTION
InadequateInletLineHoseSize  Increasehosesizetohosesize3/4”-5/8”.
WaterHammeringLiquid
Acceleration/Deacceleration
 Hoseshouldbenolongerthan50’.
RigidInletPlumbing  Use flexible wire reinforced hose to absorb pulsation and pressure
spikes.
ExcessiveElbowsinInletPlumbing  Keepelbowstoaminimumandlessthan90°.
ExcessiveLiquidTemperature  UseThermoValveinbypassline.
 Donotexceedpumptemperature104°F.
 Substituteclosedloopwithbaffledholdingtank.
 Adequatelysizedtankforfrequentorhighvolumebypass.
 Pressurefeedhightemperatureliquids.
AirLeaksinPlumbing  Checkallconnections.
 UsePTFEthreadtapeorpipethreadsealant.
AgitationinSupplyTank  Sizetankaccordingtopumpoutput-Minimum6-10timessystemGPM.
 Baffletanktopurgeairfromliquidandseparateinletformdischarge.
CloggedFilters  Performregularmaintenanceorusecleanfilterstomonitorbuildup.
 Useadequatemeshsizeforliquidandpumpspecifications.
CAVITATION DAMAGE

13
BLEACH DAMAGE
(GREEN OR BLUEISH COLOR)
NOT WARRANTED EXAMPLES
DEBRIS DAMAGE
CAVITATION DAMAGE
Oxidationdamageiscausedbythechemicalsthatpurify
waterincitywatersystems.Topreventsuchdamage,
youshouldusePumpProtector.
Debrisdamageiscausedwhentheuserdoesnotuse
afilterscreentofilterthewaterthatisconnectedtothe
pump. Without a filter, debris can flow freely into the
pump.
Bleach damage is caused by using it as a cleaning
agentwiththepressurewasher.Donotusebleachas
acleaningagent.
Cavitation damage is caused by agitated liquid that
containsairbubblesthatenterthepump.
Fig.4
Fig.6
VALVE
DEBRIS
Fig.5

14
TRIPLEX PLUNGER PUMPS
PRESSURE WASHER SYSTEM
UNLOADER TYPE
Anintegralunloaderwithbuilt-inby-passispartofthedischargemanifoldtoprovidesystempressureregulation
andpumpprotection.Thispumpalsoincludesafixedchemicalinjectorforchemicalapplication.
OPERATION
Pumpshouldbe purgedof airbeforecommencingwith operation.Liquid mustflowthroughthe pumpwithout
dischargerestrictiontoassurefullsystempressureisreached.
Installapressuregaugeclosetothemanifoldheadofthepumptoassistinsettingsystempressureandtoperiodically
monitorsystempressure.
Settingandadjustingtheunloaderpressuremustbedonewiththesystemturnedon.Startthesystemwiththe
unloaderbacked offtothelowest pressure setting(counterclockwisedirection). Squeeze thetrigger andread
thepressureonthegaugeatthepump.Donotreadpressureatthewandornozzle.Ifmorepressureisdesired,
releasethetrigger,turnadjustingcaponequarterturninaclockwisedirection.Squeezethetriggerandreadthe
pressure.Repeatthisprocessuntilthedesiredsystempressureisreached.Threadlockingnutuptoadjustingcap.
NOTE:Pressureisnotsetatthefactory.
SERVICE:
Theunloadershouldbeservicedonthesamescheduleasthesealsinthepump.
SPRAY TIP
PUMP
HIGH
PRESSURE
HOSE
SOAP
INJECTOR KIT
INLET WITH
FILTER
SPRAY WAND
WAND GRIP
THERMAL
RELIEF VALVE
POWER SOURCE
(MOTOR / ENGINE)
UNLOADER
VALVE
LANCE
SOAP
RESERVOIR
Fig.7

15
SERVICING
 1. Loosen manifold hex socket head screws. See
figure 13, page 19.
 2. Loosenvalvescaps.
 3. Looseunloadervalveandremoveunloadervalve.
See figure 15, page 20.
 4. Loosensoapinjectorassembly(U).See figure 15,
page 20.
MANIFOLD REMOVAL
 1. Usingan5mmhexkey,removethehexsocket
headscrewsfromthefaceofthemanifoldhead.
See figure 13, page 19.
 2. Insertflatheadscrewdriversoneachsidebetween
thecrankcase andmanifold head.Gently apply
pressuretotheheadtobeginseparation.
 3. Supportthemanifoldheadfromtheundersideand
pullthemanifoldheadawayfromthecrankcase.
CAUTION:
Keep the manifold head properly aligned
withtheceramicplungerswhenremovingto
avoiddamagetotheplungers.Thesealcase
may stay in the manifold or on the ceramic
plungers.
VALVE ASSEMBLY REMOVAL
NOTE:Pumprequiresonestackedvalvekitforrepair.
Discharge and inlet valve assemblies may
stay together or separate during removal.
Springretainermayalso separate fromthe
seatduringremoval.
 1. Dependingonpumpmodelusea19mmor24
mmwrenchtoremovevalveplugs(A)ontopof
manifold.See figure 8, page 18.
 2. Use reverse pliers to remove stacked valve
assembliesfromvalvechamber(C-J).
 3. Ifthedischarge valve assembly separates from
theinletvalveassembly,useareversepliersto
removeitfromthevalvechamber.
CAUTION:
Exercise caution as the reverse pliers may
damagethethreadsinvalvechamberorspring
retainer.
 4. Thespringretainer(F)mayseparatefromtheseat
(E).Removethespring(D)andvalvefromthevalve
chamber(CandI).
 5. Separatevalveassemblybyinsertingscrewdriver
intospringretainerandpressthebacksideofvalve
untilseatseparatesfromthespringretainer.
 6. Removeo-ring(BandK)fromeachseatandvalve
plug.
SOAP INJECTOR ASSEMBLY REMOVAL
 1. Remove soap injector assembly (U). See figure
15, page 20.
 2. Removesoapinjectorkit(V)fromsoap injector
assembly(U).
 3. Removespring.
 4. Removeballbearing.
 5. RemoveO-ringfrominsideassembly.
 6. RemoveO-rings(PandT),spring(S),andcheck
valves(QandR)fromcheckvalveassembly.
UNLOADER REMOVAL
 1. Removebrass adjustingcap(A) byturning ina
counterclockwisedirection.See figure 15, page 20.
 2. Removeexposedpressurespring(C)andspring
retainer(D).
 3. Usean19mmwrenchtoremovepistonretainer
(E)byturninginacounterclockwisedirection.
 4. Useneedlenoseplierstoremovepistonstemand
valveassembly(H-M).
 5. Separatepistonstem(H)fromvalve(M).Secure
the valve near the valve retainer (K). Insert a
screwdriverintoslottedheadofpistonstem(H)
andunthreadfromvalve.
PLUNGER CHAMBER REMOVAL
 1. Removelowpressureseal(A)andsealcase(B)
fromeachplungerrod.See figure 9, page 18.
 2. Useascrewdrivertopryoutthelowpressureseal
(A)fromeachsealcase(B).
 3. Carefullyinsertasmallscrewdriverorpickunder
theO-ring(C)androlltheO-ringoffeachsealcase
(B).
 4. Pressureseals(AandD)canbeeasilyremoved
fromeachsealchamberbyhandorwithreverse
pliers.Dependingonthemodelpump,youmay
needtoalsoremoveV-Packing(Not Shown) and
maleadapter(E)fromeachsealchamberbyhand
orwithareversepliers.

16
SERVICING
CERAMIC PLUNGER REMOVAL
 1. Removesealretainer(B)fromeachplungerrod.
See figure 10 page 19.
 2. Using a 10 mm hex tool, loosen the plunger
retainerbolt(E)oneachplungerrod.
 3. Removetheceramicplunger(C)andwasher(D)
from each chamber. Depending on the model
pump,theremaybeacopperretainergasketon
eachplungerretainer.Replacethecopperplunger
retainergasketwithanNBRsealwasher.
 4. Visually inspect the crankcase oil seals (A) for
deteriorationorleaks.
 5. Examinewashers(D)andreplaceifcutorworn.
 6. Examineplungersealretainers(B)fordamageand
replaceasneeded.
 7. Examine the ceramic plungers (C) for scoring,
scale buildup, chips or cracks and replace as
needed.Theceramicplungers(C)donotneedto
bereplacedwitheverysealservicing.
NOTE: Examine the manifold chamber walls, seal
chambers,andvalvechambersforscalebuildup
ordamage,cleanifneeded.Seefigure9,page18.
Cleanthemanifoldthroughly.
VALVE ASSEMBLY REPLACEMENT
 1. Examinespringretainers(FandJ)forinternalwear
orbreaksinthestructureandreplaceasneeded.
See figure 8, page 18.
 2. Examine springs (D) for fatigue or breaks and
replaceasneeded.
 3. Examinevalves(CandI)andseats(E)forgrooves,
pittingorwearandreplaceasneeded.
 4. Examineo-ring(B)forcutsorwearandreplace
asneeded.
 5. Lubricatewithsilicongreaseandinstallnewo-ring
(K)ontolargeoutsidediameterofdischargespring
retainer (J). Depending on model of pump, you
mayneedtoreinstallthebackup-ringpriortothe
o-ring.
 6. Placeseat(E)onworksurfacewithsmalldiameter
sideup.
 7. Place valve (I) onto seat (E) with concave side
down.
 8. Placespring(D)onvalve(I).
 9. Installspringretainer(F)withdeepsteppedend
overspring(D)andsnapontoseat(E).
 10. Snap discharge valve assembly onto the inlet
valveassemblyandpressintovalvechamberuntil
completelyseated.
 11. LubricatewithsilicongreaseandinstallnewO-ring
(B)ontoeachvalveplug(A).
 12. Apply thin coat Loctite 242 to threads of each
valveplug(A)andthreadinhandtight.Torqueto
specsperchart.
SOAP INJECTOR ASSEMBLY
REPLACEMENT
 1. Examine O-rings, check valves, and spring for
fatigue or breaks and replace as needed. See
figure 15, page 20.
 2. InstallO-ringinsidethesoapnozzle.
 3. Installballbearinginsidesoapnozzle.
 4. Installspringinsidesoapnozzle.
 5. Attatchsoapnozzleontosoapinjectorassembly.
 6. InstallO-ring(P)insidesoapinjectorchamber.
 7. Installcheckvalve(Q)andcheckvalvewithO-ring
(R)insidesoapinjectorchamber.
 8. Installspring(S)insidesoapinjectorchamber.
 9. InstallO-ring(T)ontosoapinjectorassembly.
 10. Attatchsoapinjectorassembly(U)tosoapinjector
chamber.
UNLOADER REPLACEMENT
 1. Ifseat (N)is worn ordamaged, pressnewseat
intounloaderchamberuntilsquarelyseated.See
figure 15, page 20.
 2. Examinepistonstem(H),washer(I),valveretainer
(K)andvalve(M)forgrooves,pittingorwearand
replaceasneeded.Examineo-rings(JandL)and
back-upring(X)forcutsorwearandreplaceas
needed.
 3. Lubricateandinstallo-ring(G)andback-upring
(X)overslottedheadofpistonstem,thenposition
back-upringontopofo-ring.
 4. Lubricateandinstallo-rings(L)onvalveretainer
(K).
 5. Installwasher(I)andthenvalveretainer(K)with
o-ringsontopistonstem(H).ApplyLocktite242
tothreadsofpistonstem(H)andscrewvalve(M)
ontopistonstem(H).
 6. Lowercompletepistonstemandvalveassembly
intounloaderchamberwithvalvefacingdownward.
 7. Examinepistonretainer(E)fordamagedthreads
orwearandreplaceasneeded.Examineo-ring
(F)forcutsorwearandreplaceasneeded.
 8. ApplyLocktite242tothreadsoflowerportionof
pistonretainer(E)intounloaderbodybyturning
in a clockwise direction and then tighten with
wrench.

17
SERVICING
 9. Examinespringretainer(D)andpressurespring
(C)forfatigueorbreaksandreplaceasneeded.
 10. Placespringretainer(D)intopistonretainer(E),
followedbypressurespring(C)aftergreasingit.
 11. Threadbrassadjustingcap(A)ontopistonretainer
(E)byturninginaclockwisedirection.
CERAMIC PLUNGER REPLACEMENT
 1. ApplyLocktite242toexposedthreadedendof
plungerretainer(E).See figure 10, page 19.
 2. Installceramic plunger(C)with sealretainer(B)
andwasher (D) overeach plunger rodshoulder
andthreadtotorquetospecsperchart,See figure
13, page 19.
NOTE: Ceramicplungerscanonlybeinstalledinone
direction.Counterboreendofceramicplunger
fitsoverrodshoulder.
PLUNGER CHAMBER REPLACEMENT
 1. Examine high pressure seals (D) or V-Packings
(Not Shown)forfrayededgesorunevenwearand
replaceasneeded.See figure 9, page 18.
 2. Examineo-rings(C)forcutsordeteriorationand
replaceasneeded.
 3. Examine low pressure seals (A) for wear to the
internalridges,outersurfacesforbrokensprings
andreplaceasneeded.
 4. Examinesealcase(B)fordeformationandreplace
asneeded.
 5. LubricateandinstallnewHi-Pressureseal(D)by
handintoeachmanifoldchamber withgrooved
side down.  Depending on the model pump, if
the pump has a male adapter (E), install it with
the notch side down. Lubricate and install new
V-Packing (Not Shown) by hand into manifold
chamberwithgroovedsidedown.
 6. Lubricateandinstallo-ring(C)oneachsealcase
(B). Press small end of seal case (B) into each
manifoldchamber.
 7. Press new low pressure seal (A) into each seal
casewiththespringtowardssealcase.
MANIFOLD REPLACEMENT
 1. Rotate crankshaft by hand so the two outside
plungersareextendedequally.
 2. Lightlylubricateceramicplungers,thencarefully
slidethemanifoldheadovertheceramicplungers,
supportingitfromtheundersidetoavoiddamage
totheplungersorseals.Pressthemanifoldhead
uptothecrankcaseuntilflush.See figure 12, page
19.
 3. Threadthehexsocketheadscrewsandtighten
intorqueinsequence.See figure 11, page 19.
 4. Tightentospecchart.See figure 13, page 19.
CRANKCASE SEAL AND O-RING
REPLACEMENT
 1. Removethefourbolts(B)fromthebearingcover
(A)onthebackofthepumpcrankcase.Remove
theseal(D)ando-ring(C)fromthebearingcover
(A).See figure 14, page 19.
 2. Examinetheseal(D)ando-ring(C)forcutsand
deteriorationandreplaceasneeded.
 3. Lubricateandinstallnewseal(D)ando-ring(C)
tothebearingcover(A).
 4. Reattachthebearingcover(A)tothecrankcase.
See figure 29, page 26 for torque spec.

18
SERVICING
Fig.8
(A)
VALVE PLUG VALVE ASSEMBLY
(G)
O-RING
(B)
O- RING
(H)
SEAL
(C)
VALVE
(I)
VALVE
(D)
SPRING
(D)
SPRING
(E)
SEAT
(E)
SEAT
(F)
SPRING
RETAINER
(J)
SPRING
RETAINER
(K)
O-RING
Fig.9
(A) LOW PRESSURE SEAL
(B) SEAL CASE
(C) O-RING
(D) HIGH PRESSURE SEAL
(E) MALE ADAPTER
SEAL CHAMBER MANIFOLD
(L)
REVERSE
PLIERS

19
Fig.10
(A)
SEAL
(B)
SEAL RETAINER
(D)
WASHER
(C)
CERAMIC
PLUNGER
(C)
CERAMIC
PLUNGER
CRANKCASE
(E)
PLUNGER RETAINER
BOLT
Fig.11
1
4
3
2
6 5
TORQUE SEQUENCE
CAT PUMP TORQUE SETTINGS
Pump Item Torque (in lbs.)
PlungerRetainer 55
ManifoldHeadScrews 132
ValvePlugs 750
BearingCoverScrews 50
BubbleOilGauge 45
Fig.12
Fig.14
SERVICING
Fig.13
CRANKCASE
MANIFOLD
(A)
BEARING COVER
(D)
SEAL
(C)
O-RING
(B)
BOLT

20
Fig.15
INTEGRAL UNLOADER
(A)
CAP
(B)
LOCK NUT
(C)
PRESSURE
SPRING
(D)
SPRING
RETAINER
(E)
PISTON
RETAINER
(G)
O-RING
(F)
O-RING
(J)
O-RING
(L)
O-RING
(O)
O-RING
(X)
BACK-UP
RING
(H)
PISTON
STEM
(I)
WASHER
(K)
VALVE
RETAINER
(M)
VALVE
(N)
SEAT
(P)
O-RING
(T)
O-RING
(Q)
CHECK
VALVE
(R)
CHECK VALVE
WITH O-RING
(S)
SPRING
(U)
SOAP
INJECTOR ASSEMBLY
(V)
SOAP
INJECTOR KIT
(Y)
QUICK
DISCONECT
SPECIFICATIONS U.S. Measure Metric Measure
Flow ............................................................................................................3.0GPM ................ (11.36L/M)
PSIRange ........................................................................................... 100-3000PSI ............ (7-206.8BAR)
InletPort..................................................................................................3/4in.GHF .............. (3/4in.GHF)
DischargePort .......................................................................................... M18x1.0 .................(M18x1.0)
UNLOADER
ASSEMBLY