46 ROLLS-ROYCE 25-30 H.P. CAR

Fig. 21. - THERMOSTAT CONTROL OF RADIATOR SHUTTERS.

CHAPTER VI

Coolant System CollantPump-RadiatorShutters-CoolantLevel-FrostPrecautions-Fan.Coolant Pump. Thecentrifugalcoolantcirculatingpumpisfittedwithaspecialdoublepackinggland. Ascrew-downgreaserisprovidedforlubricatingtheglandandbearings. It should be filled one-third full of grease every 2,500miles,asdirectedonpage19,andscrewedrightdown,preferablywhentheengineiswarm.

COOLANT SYSTEM 47

Radiator Shutters.ThethermostatwhichoperatestheradiatorshuttersisshownatT,inFig. 21,andisarrangedtomaintainanaveragecoolanttemperatureofapproximately78ºC. Referencetotheinstrumentboardthermometerwillindicatethatthethermostatisoperatingcorrectlyandthatthereisnoshortageofcoolant. In the event of faulty operation of the thermostat, the lattermaybequicklydisconnectedfromtheshutters.Thisiseffectedbyraisingthespring-loadedpin,R,anddisengagingtheendofthelever,RIfromthethermostatrod.Aknob,U,isprovidedtofacilitatere-engagement. The shutters should then be pushed open by means of the lever,RI. They must not be moved by direct hand operation of the shuttersthemselves.

Coolant Level. Thecoolantlevelshouldbeinspecteddailyandmaintanedabouthalfwayacrosstheupperradiatorpipe,asshownbuthewhiteline,L,Fig. 21. Ifananti-freezemixtureisbeingused,thelevelshouldbemain-tainedsoastojustcovertheuppertubesoftheradiatorcore.

Frost Precautions. Whereplainwaterisbeingusedasthecoolantmedium.,andthereisanyliklihoodofthecarbeingexposedtolow,frostytemperatures,withtheenginenotrunning,itisofvitalimportancethatthecoolingsystemshouldbedrainedbyopeningthedraintaponthepumpinletpipe and releasing the radiator cap. Also, after a frost and beforeattemptingtpstart,orevenmove,theengineagain,hotwatershouldfirst be poured over the water pump,asotherwisedamagemaybecausedtothepumprotorbythepresenceofparticlesoficewithinthecasing.Warmwatercanbeusedwithadvantageforrefillingtheradiator. Asuitableanti-freezemixtureismadebymixingsoftwaterwitheitherinhibitedethyleneglycolor“Bluecol”inproportionsdependentonthedegreeoffrostlikelytobeencountered. Thefollowingtablegivesanapproximateindicationoftheamountoffrostprotectionensuredbydifferentstrengthsofmixture.

Freezing point ... ... ...Degrees of frost ... ...

IInhibitedEthyleneGlycol...2”Bluecol” ............

4½ pts.4½ pts.

6¾ pts.6¾ pts.

10 pts10pts

11 pts.11pts.

22ºF.10ºF.

12ºF.20ºF.

2ºF.30ºF.

-3ºF.35ºF.

48 ROLLS-ROYCE 25-30 H.P. CAR

Fig.22.-FANBELTADJUSTMENT.

When changing from water to anti-freeze, the radiator systemmust be drained. Newanti-freezeof the required amount shouldbemixedwithanequalquantityofsoftwaterbeforebeingpouredintotheradiator,theradiatorbeingfinallytoppedupwithsoftwater. Theengineshouldthenberununtilnormaloperatingtemperatureisreached,toensureuniformdistributionoftheanti-freezethroughoutthesystem.

COOLANT SYSTEM 49

Therubberconnectionsmustbecarefullyexaminedandreplacedif unsound, as any leakagewill necessitate replenishment with anti-freeze mixture. Whenusingananti-freezemixtureasdescribed,asimilarmixtureshouldbeusedfortoppinguppurposes.Fan. ThefananditsbracketareshowninFig.22.Aspringlidlubri-cator,A, is provided, and a fewdrops of oil “C” should be injectedevery5,000miles,asdirectedonpage21..Atthesametimethejointsofthebelttensioningdeviceshouldbelubricatedwiththeoilcan. The tensionof thebeltshouldbesuch thatoneside,atapointequidistant from the pulleys, may be moved transversely with thefingersabout¾”. Theadjustmentshouldbecheckedevery2,500miles,asdirectedon page 21. Adjustmentiseffectedbyslackeningthehexagonlocknut,B,withaspannerandscrewingdowntheknurlednut,C,withthefingersuntilthecorrecttensionisobtained,afterwardssecurelyrelockingnutB.

50 ROLLS-ROYCE 25-30 H.P. CAR

CHAPTER VII

Electrical System General -Battery -Battery Ignition-SparkingPlugs -ElectricalFaultLocation.

General. The equipment comprises a dynamo, distriution box withfusesandautomaticcut-out, automaticoutput regulator, switchbox,ammeter, a12-volt approximately60-ampere-hourbattery, a startermotorwithrelay-operatedswitch,electrichornandfuelgauge,dualelectric fuel pumps and battery ignition consisting of non-tremblercoilwithballastresistance,andcombinedlow-tensioncontactbreakerand high-tension distributor and the necessarywiring encased inmetaltubing. Incorporatedwiththebatteryignitionisagovernor,whicheffectsautomaticcontrolofthebatteryignitiontiming,theeffectofthehandcontrolbeingsuperimposed. Thewiringdiagram,Fig.23,showstheunitswiththeirelectricalconnections,thevariouswiresbeingindicatedincolourstocorrespondwiththoseoftheiractualcoverings.Battery. Thebatteryrecommendedforuseonthiscariseither:- Exide ... ... ... ... 6-XCMRII-IRL or Peto&Radford ... ... 6-HZDII-S

SpecificGravityofacid(at60ºF.)

Fullycharged Exide 1.280P&R1.280

1.2011.210

Fillinginacidforfirstcharge

Exide 1.340P & R 1.350

1.2601.260

Frequentlyabove90ºF.(32ºC.).

Ordinarilybelow90ºF.(32ºC.).

Inclimateswithair temperatures

ELECTRICAL SYSTEM. 51

Exide. P.&R.First charge current ... ... 3 6Normal charge current ... ... 5 6Capacitywhenfullycharged:- Startingfor5minutes ... ... 117amps. 210amps. Lighting at 3 amperes ... ... 24 hrs. approx. 24 hrs. approx.Voltage across terminals ... ... 12 12 Neverallowtheliquidinthecellstofallbelowthetopsoftheseparators. Inspectthebatteryatregularintevals,andtopupwithdistilledwater,soastomaintaintheleveloftheliquidat½” abovethetopsofthe plates. Donotinspectthebatterywiththeaidofanakedlight,andonnoaccountdisconnectanyofthebatteryterminalsorconnectionswhenanychargeordischargecurrent ispassing,forsuchacourseincursriskofexplosionandinvolvespersonalrisk.Battery Ignition. Thebattery ignition is inaveryaccessibleposition,asshownin Fig. 24,andconsistsofanignitioncoil,W,andcombinedlow-tensioncontactbreaker,X,andhigh-tensiondistributor,XI. Aballastresistance,RI,isconnectedinserieswiththelow-tensionwindingofthecoil.Itsfunctionistolimitthecurrenttakenbythecoilatslowspeed,oriftheignitionswitchbeaccidentallyleftonwhiletheengineisstopped.Italsosecurespracticalequalityofintensityofsecondarysparkatallspeeds. Acondensorconnectedacrossthecontactpointsislocatedinapocket,X2,ofthisapparatus,thecondensorcaseandthemainbodyofthecontactbreakerunitbeingtogetherindirectelectricalcon-nectionwiththechassisframe. The insulated terminal of the condensor is connected to theinsulatedcontact,andtheyarebroughtouttogethertotheinsulatedterminaltowhichtheexternallow-tensionconnectionismade. Insettingthepointsthegapopeningshouldbe.015”to.018”. Every5,000miles,asdirectedonpage21,thepivotpinofthelow-tension rocker arm should be lubricated by moving aside theretainingspringandputtingonedropofoilontheexposedendofthepivot. A few drops of oil “C” should be injected into lubricator,Z, every2,500miles,asdirectedonpage19, inorder to lubricate thecentrifugalignitiontimingmechanism.Inaddition,theoilsoinjectedservestomaintainanoilsealarrangedatthebaseoftheignitiontowertoprotectthecontactsfromoilyvapourfromthecrankcase,whichisliabletocausepitting.

52 ROLLS-ROYCE 25-30 H.P. CAR

Fig.24.-IGNITIONCOILS,DISTRIBUTORANDBALLASTRESISTANCE.

The high-tension distributor requires no attention beyond anoccasionalwipingoftheinteriorwithaclean,dryrag. Itisimportantthattheoutsideofthecoilcasingshouldbekeptclean.Also,thecovershouldoccasionallyberemovedandthetopofthecoilcleanedwithadryrag.Misfiringissometimescausedbyanaccumulationofdirtaroundtheterminalsandonthecoilcasing.

ELECTRICAL SYSTEM. 53

Ifthetimingofthebatteryignitionshouldhavebeenderanged,due, for instance, to removal of the camoperating the low-tensionrocker,itcanbere-setbyreferencetotheflywheelmarkingswhichcanbeseenonremovaloftheclutchpitcover. Tocarryoutthisoperation,thecrankshaftshouldbeturneduntilthemarkB.A.I.(battery,advancedignition)ontheflywheelregisterswith themarkon the casingwhenNo. I piston is approaching itsfiringstroke. Owingtothefactthatafriction-dampedspringdriveisusedfordrivingthevalvegearandallauxilliaries,andthatthestartinghandleoperatestoturnthecrankshaftthroughthemediumofthisspringdrive,itisimportantthatthecrankshaftberotatedfortimimgpurposesfrom the flywheelend.Also,thestartinghandleshouldnothavebeenusedatallsincetheenginewaslastrunning. Fullyadvancetheignitionlever,andthensetthecontactbreakercamtobe juston thepointofcausingcontactbreak(when turningforward)correspondingtocylinderNo.I. A convenientmethod of determining precisely when the breaktakesplaceisbyreferencetotheammeter.Withtheignitionswitchedon,andsomeonewatchingtheammeter,thecamshouldbeslowlyrotatedon the tape of its shaft in the normal direction of rotation until therequiredpeakbreakscontactasindicatedbythereadingoftheammeter.Thescrewsecuringthecamshouldbetightened. AspareignitioncoilisprovidedasshownatWr,Fig.24. It is put into commissionby interchanging thehigh-tension terminals,H andHr,andchangingoverthetwolow-tensionleads,oneofwhichisseenat G,fromonecoiltotheother. A small casing on the dashboard, marked “Ignition Spares”,containsa spare low-tension rockerarmcompletewithspringsandcontactpoint,andalsoasparecontactscrew.Sparking Plugs. Either K.L.G. Type F.L.B. 30X or Champion Type LB.8, 14m/msparkingplugsarerecommendedforthiscar.Plugsshouldberemovedandservicedonspecialplugcleaningandtestingmachine,whichshouldbeavailableinallservicestations,every5,000miles. Resetgapsto.020”.Electrical Fault Location. Anelectrictorchhand-lampshouldbecarriedwhenmuchnightrunningisbeingdone,inadditiontoaninspectionlampwithaplugwhichmaybeconnectedtotheswitchbox. Incaseoffaultyoperation,proceedtoinvestigateasfollows:- I.Failureofanypartofthesystemseparatelymaybeduetoa blownfuseinthedistributionbox.

54 ROLLS-ROYCE 25-30 H.P. CAR Failureofincorrectoperatonofthesystemmaybeduetothefusingoftheemergenctbatteryfuseduetoanearth Repeatedfailureofaproperlyfittedfuseindicatesafaultonthesystem.

2.

Ifthedynamodoesnotcharge:-Ascertainwhetherdynamoorregulatorisatfaultbyremovingregulatorcoverandconnecting terminalI toE,andterminalA to +. This will short-circuit the regulator. Then, startengine gently and increase speed slowly. If dynamo is inorder,theoutputwillbedeliveredandthedefectwilllieintheregulator.Dynamo brushesmay be sticking, due probably to oiliness.Cleanbrushesandholderswitharagmoistenedwithpetrol.Cut-outcontactsmaybeburntorsticking.Inspectarmaturefuse,No.2,indistibutionbox.

1.

2.

3.4.

Ifdynamooputputislow,thismaybeduetobatterybeingfullycharged,butiflowwithlightson,i.e.ammeterindicatesanabnormaldischarge, the regulatormay be sticking in such amanner as per-manentlytoinsertthefieldresistance. Ifdynamogivesanexcessivechargeandblowsfuse(No.2),whenspeededup,thismaybeduetoregulatorstickingortoabreakintheregulatorshuntcoilcircuit.Checkregulatorwiringconnections. In the case of defective operation which is traceable to the regulator, the unit must be removed and returned for rectification to Rolls-Royce Ltd. If,withthefusesintact,andthelightsinorder,theignition:- (a)Misses.

1.2.

3.4.

Firstconfirmrightconditionofsparkingplugs.Assurecorrectconditionofcontactbreakerpoints,andadjustgap.015”to.018”,ifnecessary.Ifmissingstillcontinues,testignitioncircuitasbelowDirtyignitioncoilcasing.

(b)Fails.Withbatteryignitionswitchedon,seebyammeter,whileengineiscranked,thatthecoilistakingcurrentintermittently. Ifnocurrent,testavailabilityofbatteryvoltageonballastresistanceterminals then at coil terminals.

1.

If,withbatteryinorder,startermotorissluggishordoesnotturn,examinecommutator andbrushes. Cleanoilybrushes andholderswith a ragmoistenedwith petrol. If motor turns without turningengine,examineBijurdrive. Ifbatterywillnotretaincharge:- 1.Ascertainthatnocircuitisleftswitchedon. 2.Seethatnocellofthebatteryleaksacid.

Fig.25.-GUIDETOLOCATIONOFMAINSERVICESTATION.

Fig.26.-GUIDETOLOCATIONOFCREWESERVICESTATION.