XS Scuba MultiMax User manual

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XS Scuba MultiMax Breathable Inator Service Manual
MultiMax Breathable Inflator Service Manual

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XS Scuba MultiMax Breathable Inator Service Manual
Table of Contents
Introduction     2
Warnings,CautionsandNotes   2
MaintenanceSchedules   3
StandardProcedures    3
NitroxCompatibility    3
Pre-Test&InspectionPriortoDisassembly 4
RequiredTools     4
ExplodedDiagramsandPartLists  5
Introduction
Thismanualoutlinesmanufacturerprescribed
servicingproceduresfortheregulatorproduct
describedwithin.Itcoversdisassembly,cleaning,
inspection,reassembly,adjustingandtestingofsaid
regulatorproduct.Thispublicationassumesthatthe
technicianperformingtheserviceisexperienced,
Document Change Notice (DCN)
Warnings, Cautions and Notes
Payspecialattentiontoinformationprovidedinwarnings,cautionandnotesthatareaccompaniedbyoneof
thesesymbols:

  WARNINGindicatesaprocedureorsituationthatmayresultinseriousinjuryordeath
 ifinstructionsarenotfollowedcorrectly
  CAUTIONindicatesanysituationortechniquethatwillresultinpotentialdamagetothe
  product,orrendertheproductunsafeifinstructionsarenotfollowedcorrectly
  NOTEisusedtoemphasizeimportantpoints,tipsorreminders
MultiMaxDisassembly   6
CleaningProcedures    11
PreparingandInspectingParts   11
RecommendedCleanersandLubricants 12
MultiMaxReassembly    13
AdjustingandTesting    18
TroubleshootingGuide    22
TestBenchSpecications   22
Page # Rev. Date Revision Made
All 06/01/2020 FirstRelease
mechanicallyinclined,isusingthepropertools,
partsandproceduresprescribedwithin.Ifyoudo
notfullyunderstandalloftheproceduresoutlined
inthismanual,contactXSScubaandspeakwitha
TechnicalAdvisorbeforeproceedinganyfurther.

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XS Scuba MultiMax Breathable Inator Service Manual
Maintenance Schedules
Breathableinators,suchastheMultiMax,aresubjected
toavarietyofenvironmentalelementsthatovertimecan
affecttheirperformance.Salt,sand,sediment,chlorine
andotherchemicalsalltaketheirtollonabreathable
inator.Softpartswearoutandlubricantsbreakdown
andwashaway.AsanXSScubaDealer,youareadvised
toinformyourstaffandcustomersthattheXSScuba
MultiMaxrequiresservicingatleastonceayear.Under
certaincircumstancesserviceisrequiredevery3-6
months.Someofthosecircumstancesare:
1. Frequentorimproperuse
2. Inadequateroutinefreshwaterrinsing
3. Regulatoruseindirtyorpollutedwaters
4. Rentaluse
5. Regularuseinchlorinated(pool)water

Recommendedmaintenanceschedulesarebasedon
averageuseundernormalconditionsandassumethat
recommendedpreventativemaintenanceandstorage
procedureshavebeenfollowedasoutlinedinthe
XSScubaMultiMaxOwner’sManual.
Standard Procedures
1. Previewthelistoftoolsandpartsrequiredtoperform
theprescribedserviceoutlinedinthismanual.Follow
eachstepinthesequenceprovided.Havethismanual
opennexttoyouforreference.Donotrelyupon
memory.
2. NumbersfoundinparenthesisreferencetheKEY
numbersintheexplodeddiagrams.Ifyouarenotsure
whatapartisbyitsdescription,usethisnumberto
crossreferenceitintheexplodeddiagram.
3. Allregulatorservicesshouldbeperformedona
workbenchspecicallysetupandequippedforthis
purpose.Adequatelightingandcleanlinessalong
witheasyaccesstotherequiredtoolsshouldbe
consideredmandatory.
4. Delicateparts,suchaspartswithcriticallymachined
surfacesshouldbeisolatedfromtheotherparts
topreventdamage,especiallyduringthecleaning
procedure.
5. Onlyusefactoryauthorizedpartsprovidedby
XSScuba.Donotattempttosubstituteother
manufacturer’spartsregardlessofanysimilarityin
appearance.Thisisespeciallytrueforo-rings!
6. Donotattempttoreusemandatoryreplacement
partsregardlessofhowmuchusethosepartswere
subjectedto.
7. Whenreassembling,itisimportanttofollowfactory
mandatedtorquevaluesusingacalibratedtorque
wrench.Todootherwisecouldleadtodamageor
failureoftheproduct.
8. Unlessotherwiseinstructed,thefollowingis
assumed:
a. Wheninstructedtoremove,unscrewor 
 loosenathreadedpart,turnthepart  
 counterclockwise.Themanualabbreviates 
 counterclockwisewithCCW.
b. Wheninstructedtoinstall,screwinortighten
 athreadedpart,turnthepartclockwise. 
 ThemanualabbreviatesclockwisewithCW.
9. Thefollowingabbreviationsareusedthroughoutthis
manual:
a.HP=HighPressure–thepressureenteringa
 regulatorfromthecylindere.g.3000psi
b.MP=MediumPressure–thepressureleaving
 therststagetravelingtothe2ndstage.Also 
 referredtoasintermediateorinterstagepressure
c.LP=LowPressure–thepressureexitingthe
 2ndstagethroughthemouthpiece.Alsoreferred
 toasambientpressure.
Nitrox Compatibility
SincetheMultiMaxoperateswithasupplypressure
below145psi(10bar),elevatedpercentagesofoxygen
arenotaconcernwiththisproduct.

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XS Scuba MultiMax Breathable Inator Service Manual
Pre-Test and Inspection Prior to Disassembly
ItisgoodpracticetoinspecttheMultiMaxpriortodisassemblyandtodocumentyourndings.Thiswillhelp
youidentifyanyproblemssoyoucanbesurethattheseproblemsgetremediedduringservice.Youcanusethe
followingchecklistforitemstodocument.
1. CharacterizetheoverallconditionoftheMultiMax.Isit“likenew”orisitscratched,nickedorheavilycorroded?
2. Observetheconditionofthebraidedhosewhereitexitsthecrimpedferrules.Ifthebraidispullingoutofthe
crimpsorifthebersareabraded,documentandplanonreplacingit.
3. IftheMultiMaxisattachedtoaregulatorrststage,attachanintermediatepressuregaugetotherststageand
recordthemediumorinterstagepressure.Recordthevalue.
4. PressurizetheMultiMaxandsubmergeinatubofwater.Arethereanyleaks?Ifso,documentwheretheleaks
arecomingfrom.
5. PurgetheMultiMax.Isthepurgestrongorweak?Istherefreeoworleakingafterpurging?
6. Attachtomagnehelicorconductasubjectivebreathingevaluationtoevaluatetheopeningeffort.Document
yourndings.
7. Operatethepowerinationbutton.Doesitprovideanice,strongination?Doesitgetstuckorleak?
8. Operatetheoralinationbutton.Doesitsealofftheexhaustvalve,routingyourexhalationoutthecorrugated
hoseconnection?Doesitgetstuckorleak?
Required Tool List
Part # Description Application
TL111 O-ringpick Removingo-rings
n/a SmallFlatHeadScrewdriver Coneseat(11)
n/a MediumFlatHeadScrewdriver Purgecover
retainerring(42)
n/a Coin(preferablyaU.S.nickel) Threadedcap(9)
n/a 90°pliersorcirclippliers Exhaustcover(15)and
exhaustretainer(17)
TL136 Multi-PurposeTool Extractcableretaining
pin(5)
n/a Plierswrappedwithtape InstallC-clip(7)
n/a 5.5mmsocketornutdriver Nylocnuts(19)x2
n/a Smallcrescentwrench Valvehousing(35)
n/a 13mmopen-endwrench Inletstem(28)
TL138 MultiMaxValveAssemblyTool Assemblebreathingvalve

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XS Scuba MultiMax Breathable Inator Service Manual
MULTIMAX
BREATHABLE INFLATOR
# Part # Description
RK14 Service Kit, MultiMax
47. RP370-45 Svc Kit for QD Coupler
1. RP370-01 1" Hose Connector Assy.
2. RP370-02 Threaded Collar
3. RP370-03 Hose Connector
4. RP370-04 O-ring
5. BP625 Retainer Pin
6. RP370-06 Dust Cap
7. RP370-07 C-clip
8. RP370-08 Main Body
9. RP370-09 Threaded Cap
10. RP370-10 O-ring
11. RP370-11 Cone Seat
12. BPH10 O-ring
13. RP370-13 Spring
14. RP370-14 Inflation Button
15. RP370-15 Exhaust Cover
16. RP370-16 Exhaust Valve
17. RP370-17 Exhaust Retainer
18. RP370-18 O-ring
19. RP370-19 Nut
20. RP370-20 Exhaust Seal
21. RP370-21 O-ring
22. RP370-22 Washer
23. RP370-23 Spring
24. RP370-24 Oral Button
25. RP370-25 Mouthpiece
26. RP370-26 Miflex Hose, 26", CN/BU
27. RP370-27 O-ring
28. RP370-28 Inlet Stem
29. RP370-29 O-ring
30. RP370-30 Crown Orifice
31. RP370-31 Seat
32. RP370-32 Stem
33. RP370-33 Seat Retainer
# Part # Description
34. RP370-34 Spring
35. RP370-35 Valve Housing
36. RP370-36 Housing Insert
37. RP370-37 Lever
38. RP370-38 Washer
39. RP370-39 Diaphragm
40. RP370-40 Diaphragm Washer
41. RP370-41 Purge Cover
42. RP370-42 Retainer Ring
43. RP200-29 O-ring
44. RP370-43 No-Bump Tie Wrap
45. RP200-19 O-ring
46. RP370-44 QD Coupler
Part numbers in bold italics are standard replacement
parts and found in the RK14 service kit
47
45
26
13
14
15
16
19
20
21
22
23
24
26
19
26
43 46
1
2
3
4
13 12 14
24
23
22
21
8
39
40
41
42
19
38
37
36
35
34
33
32
31
30
29
28
27
27
44
25
15 16 17
910 11 12 7
6
5
18 19
20

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XS Scuba MultiMax Breathable Inator Service Manual
MultiMax Disassembly Procedure
1. Remove the MultiMax from the corrugated
hose.
Option 1 – Leave the hose connecter attached to
the corrugated hose

a.Unthreadcollar(2)fromtheMultiMaxbody(8).

b.Pullthehoseconnector(3)outofthebody(8).

c.Removetheo-ring(4)fromthehoseconnector(3).


Option 2 – Remove the hose connector from the
corrugated hose

a.Cuttheziptiethatsecuresthecorrugatedhoseto
theMultimax.Pullbackthehose.

b.UsetheMulti-PurposeTool(TL136)topushout
thecableretentionpin.

c.SeparatetheMultiMaxfromthecable.
2. Remove the top cover assembly
a.Usingamedium,atheadscrewdriver,disengage
the4tabsontheretainerring(42)fromthe
mainbody(8).

b.Liftoffpurgecover(41),diaphragmwasher(40)
 anddiaphragm(39)

3. Remove power inator button assembly
a.Usinganappropriatelysizedcoin(U.S.nickel),
engageandremovethethreadedcap(9).

b.Removethethreadedcapo-ring(10).

c.Whiledepressingthepowerinatorbutton(14),
removetheconeseat(11),usingasmallathead
screwdriver.

d.Removethesmallo-ring(12)fromtheconeseat(11).

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XS Scuba MultiMax Breathable Inator Service Manual

e.Removetheinationbuttonassembly(14)and 
thespring(13)fromthemainbody(8).

f.Removethesmallo-ring(12)fromtheination 
button(14)

CAUTION:Theinationbuttonassembly
(14),whichiscomprisedofabuttonandshaft,isnot
designedtocomeapart.Donottrytoseparatethem.

4. Remove the exhaust assembly

a.Removetheexhaustcover(15)

i.Ifyouhavestrongngers,itmaybepossibleto
unscrewbyhand

ii.Otherwise,unscrewitbyusingapairof90° 
pliersorcirclipplierstoengageeithersideof 
thecrossmember.

b.Liftopposingedgesoftheexhaustvalve
(likeataco)toexposethespokesoftheexhaust 
retainer(17).

i.Asbefore,ifyouhavestrongngers,engage 
thespokesandspinouttheexhaustretainer(17)

ii.Otherwise,useapairof90°pliersorcirclip
plierstoengagethespokesandspinoutthe 
exhaustretainer.



NOTE:Inspecttheexhaustvalve(16).Ifitis
cleanandhaswelldenededges,itmayremainin
placeandreused.Thisisusuallythecase.Itisnot
consideredamandatoryreplacementpart.

c.Removetheo-ring(18)fromtheexhaustretainer(17).

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5. Remove the oral ination assembly

a.Usinga5.5mmsocketornutdriver,remove
thenylocnut.
b.Removetheexhaustseal(20)

c.Removetheoralbutton(24),spring(23),washer
(22),ando-ring(21).


Iftheoring(21)doesn’tcomeoutwiththeoral
buttonassembly,itprobablyremainsnestledinthe
mainbody(8).Locateandremoveit.


NOTE:Iftheo-ringdoesnotcomeoutonthe
buttonshaft,itmaystillbeseatedinthemainbody.
Pleaselocateandremoveit.
6. Disassemble the breathing valve
a.Carefullypulloffthedustcap(6).

b.Usingasmall,atheadscrewdriver,disengage
theC-clip(7).Exercisecautionnottobenditasit
willnormallygetre-used.

c.Withyourforenger,pushontheinletstemto 
removetheentirebreathingvalvesub-assembly 
fromthemainbody(8).

d.Separatethebreathingvalveassembly
i.Whileholdingthevalvehousing(35)stationary 
withasmallcrescentwrench,removetheinlet 
stem(28)witha13mmopen-endwrench.

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
e.Separatetheinletstem(28)assembly
i.Usingthumbandforenger,removethecrown 
orice(30)fromtheinletstem(28)bypullingit 
straightout.
ii.Removetheo-ring(29)fromthecrown
orice(30)

iii.Removethetwoo-rings(27)fromtheinlet
stem(28).

f.Separatethevalvehousing(35)assembly
i.Usinga5.5mmsocketornutdriver,remove
thenylocnut(19).


NOTE:Thepartsareinsidethevalvehousing
(35)areunderspringtension.Whenremovingthenut,
thepartscouldejectoutofthevalvehousingunless
youcoveritwithyourhand.

ii.Locateandidentifythenut(19),washer(38),
lever(37),valvehousing(35),spring(34),stem 
andseatassembly.


iii.Removethehousinginsert(36)fromthevalve 
housing(35).

iv.Removetheseat(31),byretractingtheseat 
retainer(33).

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

7. Mouthpiece
a.Inspectthemouthpiece(25)andtiewrap(44).
Iftheyareingoodcondition,theycanremain
inplaceandgetcleanedwiththemainbody(8).

8. Remove hose connector (3)
a.WhenyouremovedtheMultiMaxfromtheBC,if
youleftthehoseconnectorassemblyon,you
canremoveitnow.Unthreadthecollar(2)from 
thebody(8).
b.Pullthehoseconnector(3)outofthebody(8).
c.Removetheo-ring(4)fromthehoseconnector(3).




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Cleaning Procedures
Allreusableparts,metallicandsoft,shouldbecleanedina
warm(notover120°F/50°C)dishsoapandwatersolution.
Useasoft,nylonbristlebrushtoremoveanystubborn
deposits.Thedishsoaphelpstoremovegreaseandold
lubricant.
Plastic and Rubber Parts
Aftercleaning,rinseinfreshwater.Ifyourlocaltapwateris
hard,considerusingdistilledwater.Drywithhyper-ltered
compressedair.
Metallic Parts
WARNING:Besuretousehandandeye
protectionwhenhandlingchemicalcleaningsolutions.
Whiledishsoapisanexcellentdegreaser,itmaynotremove
corrosionandmineralbuilduponmetallicparts.Thatiswhere
acidiseffective.Metalpartsmaybeimmersedinasonic
cleanerwithadilutedaceticacid(vinegar)andwatersolution
(50:50)
Ifyoureallywantyourmetalpartstosparkle,considerusinga
dilutedsolutionofOakite31inyoursoniccleaner.Besureto
followthemanufacturer’sinstructionsfordilution.
Aftercleaning,rinseinfreshwater.Ifyourlocaltapwateris
hard,considerusingdistilledwater.Drywithhyper-ltered
compressedair.
CAUTION:Neverplacesoftpartse.g.rubber,
plastic,urethanes,siliconesintoanyacidicsolutions.
Doingsomayaltertheirphysicalproperties,causing
themtobreak,degradeprematurelyornolongert.
NOTE:Manytechniciansndthatasolutionof
diluteddishsoapanddilutedvinegarintheirsonic
cleanerisalltheyneedtocleanthemetalparts.Itis
inexpensiveandveryeffective.
Cleaning Hoses
Youmayrunwarmsoapywater(notover120°F/50°C)
throughtheregulatorhose.Rinsethoroughlyandthenblow
hyper-lteredairthroughituntildry.
Iftheendttingsarecorroded,installXSScubahoseplugs,
p/nTL129,tosealthehoseends.Thettingsmaythenbe
brieyimmersedintoadilutedacidicsolutioninasonic
cleaner.Again,rinsethoroughlydry.
WARNING:Donotallowanyacidicsolutionor
othercleaningagent,otherthandishsoap,toenter
theinsideofthehose(s).Doingsomaycausea
breakdownoftheinnerhoseliningwhichcanleadto
obstructionoftheairpassageway.
Preparing and Inspecting Parts
Nitrox Preparation
Ifyouarepreparingtheregulatortoplacebackinto
nitroxservice(O2nottoexceed40%),youshoulduse
powderlesslatexornitrileglovestokeepngeroilsoffof
thecleanparts.
O-rings:AllO-ringsshouldbereplacedateveryservicing.
NewO-ringsshouldbeinspectedforcontaminationand/
orimperfections,andlightlydressedwithathinlmof
approvedlubricantpriortoinstallation.SeeRecommended
CleanerandLubricantTablebelow.O-ringsthatsurround
ltersdonotneedtobelubricated.
CAUTION:Donotuseanypetroleumbased
lubricantsorproducts,oranyaerosolsiliconesprays
onanypartoftheregulator.
Diaphragm: Thediaphragmshouldbeinspectedforany
holesorcutsthatcouldallowwatertoenterthehousing.
Thebestwaytoconductthisinspectionistostretchthe
diaphragmovertheendofyourngertoenlargeanysmall
holesandmakethemvisible.Byprogressivelyworking
aroundthediaphragminthismanner,holesthatmight
havegoneunnoticedcanbeeasilylocated.Payparticular
attentiontotheareanearthecenterplate.Ifthediaphragm
isdamagedinanyway,itshouldbereplaced.
NOTE:Diaphragmsareneverlubricated.
Exhaust Valve:Theexhaustvalveshouldbeclosely
examinedwhileinthemainhousing.Becausetheskirtof
theexhaustvalveisverythin,itissusceptibletowearand
tears.Ifanyimperfectionsarefound,replaceitwithnew.
Crown Orice: Thecritically-machinedsealingedgeof
thecrownoriceisimportanttoreducingsealingforce.
Thesealingedgemustbefreefromnicksorscratchesand
squarewiththecenterlineoftheorice.Anyimperfection
canallowsmallamountsofairtoleakbetweentheorice
andsoftseat,andrequireexcessivespringpressuretoseal
airtight.Thesealingedgeofthecrownoriceshouldbe
inspectedundermagnicationwheneverpossible.
Itisalsoveryimportanttoprotectthecrownoricesealing
edgeduringthedisassembly,assemblyandcleaning
operations.Normally,thecrownoriceisnotreplaced
duringservice.

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Lubricant / Cleaner Application Source
Liquiddishwashingdetergent
dilutedwithwarmwater
Degreaserforallmetallicparts;
generalcleaningsolutionforplas-
ticandrubberparts
Householdgrade-“Dawn”works
verywell
Vinegar(aceticacid)-diluted Removescorrosionandmineral
buildupfrommetallicparts
Householdgrade
Oakite31dilutedwithwater Useinsoniccleanertoclean
metalparts
OakiteProducts,Inc.
50ValleyRoad
BerkeleyHeights,NJ07922
www.chemetallna.com
Christo-lubeMCG111 o-ringdressing XSScuba
4040WChandlerAve.
SantaAna,CA92704
866.977.2822
www.XSscuba.com
Tribolube71 o-ringdressing AerospaceLubricants
1600GeorgesvilleRoad
Columbus,Ohio43228
614.878.3600
www.aerospacelubricants.com
Recommended Cleaners and Lubricants

13
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MultiMax Reassembly Procedure
1. Install power inator button assembly

a.Installanew,lubricatedo-ring(12)ontothepower
inatorbuttonassembly(14).
 
b.Passtheshaftofthebuttonassembly(14)through
thespring(13)andinsertthroughthemainbody(8).


c.Installanew,lubricatedo-ring(12)intothecone 
seat(11).

d.Whiledepressingthepowerinatorbutton,thread
theconeseat(11)ontobuttonshaft(14). 
Tightenwithasmall,atheadscrewdriveruntil 
snug.
e.Installanew,lubricatedo-ring(10)ontothe 
threadedcap(9)

f.Threadthecap(9)intothemainbody(8).Tighten
withacoinuntillightlysnug.

2. Install the oral ination assembly

a.Generouslylubricateo-ring(21)andinstallintothe
mainbody(8).

b.Passthestemoftheoralbuttonassembly(24)
throughtheconicalspring(23)andthemetal
washer(22).Thelargediameterofthespring
(23)goesupagainstthebutton.Thenarrowend 
towardsthebody(8).
c.Inserttheshaftofthebuttonassembly(24),with 
thespring(23)andwasher(22),throughtheo-ring
(21)inthemainbody(8).

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d.Whilepressingtheoralbutton,placetheoralseal
(20)overtheendoftheshaftwiththeexposed 
metalcenteroftheoralseal(20)facingup.

e.Installanewnylocnut(19)ontotheshaft.Thread
itonwitha5.5mmsocketuntilsnug.Theoral 
sealshouldbesecureontheshaftandwithout 
anywobbleorplay.
3. Install the exhaust assembly
a.Installanew,lubricatedo-ring(18)ontothe
exhaustvalveretainer(17).Itisassumedthatthe
originalexhaustvalve(16)isstillinstalledintothe
exhaustvalveretainer(17).

b. Installtheexhaustvalveretainer.

 i.Lifttheopposingedgesoftheexhaustvalve
 (16)likeataco,toengageyourthumband
 forengerinbetweenthespokesoftheexhaust
 valveretainer(17).

 ii.Threadtheexhaustvalveretainer(17)into
themainbody(8).Threaditinasfaras 
youcanusingyourngers.Threaditinthe
remainderofthewayusinguseapairof90° 
pliersorcirclippliersuntilitbottomsout.


CAUTION: Over-torqueingtheexhaustvalve
retainer(17)willresultinoneormorebrokenspokes.
Thisrequiresthattheexhaustvalveretainer(17)be
replaced.
c.Installtheexhaustvalvecover(15).

i.Threaditonwithyourngersoruseapairof
90°pliersorcirclippliersuntilitreachesahard
stop.

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4. Building the valve housing assembly
 
a.Iftheseatretainer(33)hasbeenremovedfrom 
thestem(32),slideitupthestem(32)andback 
intoplace.

b.Installanewseat(31)bypressingitintotheseat
retainer(33).Itshouldsitushwiththeseat 
retainer(33)walls.

c.Installthehousinginsert(36)intothevalve 
housing(35).

d.Placethestemandseatassemblyfacedownon
topofthevalveassemblytool.

e.Placethespring(34)overthestem(32).

f.Lowerthevalvehousing(35)overthestem(32)
andspring(34)andthreadontothevalve 
assemblytool.Thesquareportionofthestem
(32)seemstonditswayintothesquareholeof 
thevalveinsert(36).

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
NOTE:Whenthreadingthevalvehousing(35)on
tothevalveassemblytool,ifthesquareportionofthe
stem(32)doesnotalignwiththesquareholeinthe
valveinsert(36),itwillunseatthevalveinsert(36).


Ifthishappens,removerthevalveinsert(36),rotate
thestem(32)withasmallpairofplierssothatthe
squareportionofthestem(32),isparallelwiththeslot
ofthevalvehousing(35).Seeimagebelow.



Nowyoucanaddthewhitevalveinsert(36).Make
surethatitisseatedallthewaydownontothevalve
housing(35).

g. Installthelever(37).

 i.Thelever(37)MUSTbeorientedopposite
 theovalhole.

CAUTION:Wheninstallingthelever(37),itmust
beorientedoppositetheovaloutlethole.

h.Placewasher(38)overthethreads.

i.Threadnylocnut(19)ontothethreadedshaft. 

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i.Usinga5.5mmsocketornutdriver,drivethe 
nut(19)untilthereisonethreadshowingabove 
thenut(19).Thisisthepreliminaryadjustment.
j.Separatethevalveassemblyfromthevalve 
assemblytool.

5. Assembling the inlet stem
a.Installanew,lubricatedo-ring(29)ontothecrown
orice(30).

b.Installnew,lubricatedo-ringsontotheinletstem
(28).
c.Presstthecrownorice(30),o-ringsiderst,into
theinletstem(28).

6. Assembling the breathing valve

a.Threadtheinletstemassemblyandthevalve 
housingassemblytogether.Whendoingthis,
pressdownonthelever(37)toretracttheseat(31).
Thiskeepstheseatawayfromthecrownorice 
(30),preventingunnecessarywearwhiletheparts
arebeingrotated.
CAUTION:Whilematingtheinletstemassembly
tothevalvehousingassembly,pressdownonthe
lever(37)toretracttheseat(31).Thiskeepsthe
seatawayfromthecrownorice(30),preventing
unnecessarywearwhilethepartsarebeingrotated.

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b.Usingasmallcrescentwrenchonthevalve
housing(35)anda13mmwrenchontheinlet
stem(28),tightenthetwosubassembliesuntil 
snug.

7. Installing the breathing valve into the body
a.Respectingtheindexingatsinsidethebody(8)
andonthevalvehousing(35),andwiththelever 
facingawayfromthemouthpiece(25),insertthe 
entirebreathingvalveassemblyintothebody(8).

b.AligntheC-clip(7)withtheloweroftwogrooves
ontheinletstem(28)andsqueezeintoplaceusing
plierswrappedwithtapetoprotectthenish.




c.Installthedustcap(6).Seatitintothegroovejust
abovetheC-clip(7).

8. Final assembly occurs during Testing and
Adjusting
Adjusting and Testing
NOTE:Therearetwoadjustmentsonthe
MultiMax.
1.Thecrownorice(30),whichcanbedriven
inandoutbyinsertinga3/16”hexwrench
 throughtheinletstem.TurningCWreduces
thedistancebetweenthecrownorice(30)
andtheseat(31)andincreasestheopening
 effort.TurningCCWincreasesthedistance
 andreducestheopeningeffort.
 2.Thenylocnut(19),setsthespringtension
 aswellasleverheight.Itgetsrotatedwith
the5.5mmsocketornutdriver.

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1. Pressurize the unit

a.AttachtheMultimaxtoproperlyfunctioningrst 
stageregulator(preferablythecustomer’srst
stage)ordirectlytoaowbench.Ifyoudonot
knowtheexactintermediatepressureleavingthe
customer’srststage,thenuse140psi,whichis
averycommonintermediatepressure.Besure 
thattheintermediatepressurecomingintothe
MultiMaxisstableandnotcreepingup.

NOTE:ItisalwaysbesttoadjusttheMultiMax
toyourcustomer’srststage.Whentheybringintheir
MultiMaxforservice,havethembringintheirrst
stagealongwithit.
2. Adjustment of the crown orice (30)
a.AttachtheMultiMaxquickcouplertotheinlet
stemandslowlyturnontheair.Thereshouldbe
anaudibleleak.

b.Disconnectthequickcoupler,insertthe3/16”hex
wrench,engagethebackofthecrownorice(30)
andturnitinward,CW,¼ofaturn.Reconnectthe
coupler.Iftheleakstillexists,removethecoupler,
turnthecrownorice(30)inanother¼turnand
tryagain.Continuethisprocedureuntiltheleak
juststops.

c.Oncetheleakstops,thendriveitinfurtheran
additional¼turnforconservatism.

NOTE:Theprocedureabovecanbetedious
asitrequiresalternatingbetweenpressurizingand
adjusting.Here’satechnician’stip:insteadofattaching
thecouplerbetweeneachadjustment,justblowinto
theinletstemandlistenforanaudibleleak.Drivein
thecrownorice(30)inalittleatatimeuntilyoucan’t
blowairthroughitanymore,thenturnthecrownorice
(30)anadditional¼turnforconservatism.It’squick
andeasy!

3. Adjusting the nyloc nut to optimize lever
height and tension
 NOTE:Thenylocnut(19),aftersettingitearlier
toitspreliminarysettingofjustonethreadshowing,will
probablynotevenneedadjustment.
a.Thenylocnut(19)playsaroleinsettingthelever
heightandlevertension.Whilepressurized,thetip
ofthelevershouldbeapproximately2mmbelow
therimofthebody(8)andhavelessthan1/8”of
“slack”.

b.However,ifafterpressurizingtheunit,theleversits
toolowortheleverhastoomuch“slack”init, 
you’llneedtotightenthenylocnut(19)insmall
increments.Asyoudoso,thelevershouldrise,and
the“slack”shouldminimize.

c.Ifyoutightenthenylocnut(19)toomuch,youwill
causetheseat(31)toliftawayfromthecrown
orice(30)causingaleak,andyouwilltightenthe
spring(34)causingincreasedinhalationeffort.
4. Final assembly

a.Diaphragm/purgecoverassembly

i.Installthediaphragm(39)anddiaphragmwasher
(40).
CAUTION:Acommonerroristoinstallthe
diaphragmwasher(40)upsidedown.Thewideange
ofthediaphragmwasher(40)sitsonthediaphragm
(39).



20 www.XSscuba.com
XS Scuba MultiMax Breathable Inator Service Manual
 ii.Fitthepurgecover(41)intotheretainerring 
 (42)
 
 iii.Pressintoplacebyinsertingthe4tabsinto 
the4slots.BesurethattheXSScubalogoisnot
 upsidedown.

b. Ifyoutookthemouthpiece(25)off,replaceit 
now.

c. Installhoseconnectorassembly

 i.Slideo-ring(4)ontothehoseconnector(3).
 
 ii.Insertassemblyintothebody(8).

 iii.Securethreadedcollar(2)tolockintoplace
 
 iv.Ifthehoseconnector(3)wasremovedfromthe
 BC’scorrugatedhose,thenreattachittotheBC.

d.AttachMultiMaxtotheBC’scorrugatedhose
 iInsertthecableretainingpinhalfwaythroughthe
 hoseconnector(3)
 iiPlaceloopofrapidexhaustcableoverthepin
 iiiEngagethepinintothefarwallofthehose 
 connector(3)

 ivPushthehoseoverthehoseconnector(3) 
 beingverycarefulnottoletthecableretainingpin
 disengagefromeitherwallofthehoseconnector(3)
 v.Applyanewzip-tie.
