《港口机械与电气专业》-Lesson 36The Engine Maintenance Ⅲ

TextContentsfuelinjector 喷油器needlevalveassembly 针阀偶件fuelinjectortester 喷油器试验器fuelinjectionpump 喷油泵sealsurface 密封面decompressionzone 减压环带outletvalve 出油阀carbondeposition 积炭

electrodegap 电极间隙short-circuit 短路opencircuit 断路ground 搭铁additionalresistance 附加电阻disassemble 拆卸reassemble 重新装配thermostat 节温器TextThispassageisconcernedaboutmaintenanceforfuelsystem,ignitionsystem,lubricatingsystemandcoolingsystem.MaintenanceforthefuelsystemFirstly,let’spayourattentiontotherepairforafuelinjector.Theneedlevalveassemblyoftenwearsduringoperation.Forwithslightwear,millingbyhandisalwaysused.Butforexcessivewearandseriousleak,justreplaceanewone.CheckandadjustmentforthefuelinjectorisshowninFigure36-1.Figure36-1Checkandadjustmentforthefuelinjector1—Fuelinjectortester;2—Adjustingscrew;3—Fuelinjector;4—Forthree-wayunion;5—pumpSecondly,let’sturntorepairforafuelinjectionpump.Itisnecessarytomentiontherepairforoutletvalvecoupleparts.Thewearofoutletvalvecouplepartsmainlyoccursonsealsurfacebetweenvalveandvalveseatordecompressionzoneoftheoutletvalve.Testsareoftenmadetotesttheoutletvalvecoupleparts(Figure36-2).Orsometimeswemayuseeasymethod(Figure36-3).Figure36-2Testfortheoutletvalvecoupleparts1—Outletvalveholder;2—Outletvalve;3—Testingfixture;4—Headscrew

MaintenancefortheignitionsystemInthispart,wewillmainlydealwiththerepairforsparkplug,ignitioncoilanddistributor.Themaindefectofasparkplugiscarbondeposition,crackontheinsulatorandexcessivegapofelectrode.Theusualelectrodegapisabout0.6-0.7mm.WecanusethemethoddisplayedinFigure36-4tocheckandadjustthegap.Themaindefectofignitioncoilisshort-circuit,opencircuitorgroundoftheprimarycoilandsecondarycoil,orshort-circuit,groundorburn-outofadditionalresistance.Thecheckforignitioncoilconsistsof:(1)checkforadditionalresistanceandlowvoltagecoil,(2)checkforhighvoltagecoilandinsideinsulatingproperty.Figure36-3EasymethodFigure36-4MethodtocheckandadjustthegapTheoverhaulofthedistributorincludes:Checkforspringleafelasticofmovingthecontactarmofabreaker(Figure36-5);(2)Checkforthemovingcontact;(3)Checkandadjustmentforthecontactclearance(Figure36-6);(4)Checkandrepairforthedistributorcapanddistributorrotor;(5)Checkforthecapacitor.Figure36-5Checkforthespringleaf

MaintenanceforthelubricatingsystemTheoilpumpsusedonmostenginesarethevolumetypeoilpump.Themainfailureofthiskindofpumpisthepoorsealingperformanceaftersomeparts’wear.Thepoorsealingperformancealwaysleadstolowsupplypressure.Figure36-6Checkandadjustment

Generallyspeaking,wecanrefertothefollowingstodotheoilpumpmaintenance.(Figure36-7)(1)Disassembletheoilpump;(2)Repairtheoilpump;(3)Reassembletheoilpump;(4)Testtheoilpump.Figure36-7Oilpumpmaintenance

Fortheoilfiltermaintenance,wemainlydealwiththemaintenancefortheroughfilterandmaintenancefinefilter.Thefilterelementusedontheroughfilterconsistsofmetalfilterelementandpaperfilterelement.Thepaperfilterelementneedn’trepair.Wecanjustchangeanewoneiftheoldonedoesn’tworkwell.Butthemetalfilterelementneedsrepair.Forthefinefilterwiththepaperfilterelement,onlythehousingandcentraltubeneedscleaning.Itsfilterelementcanbechangedeasily.Maintenanceforthecoolingsystem

Thispartismainlyaboutmaintenanceforthewaterpump,radiatorandthermostat.Thecommoninjuryofthewaterpumpisofleakageorruptureofthepumphousing,bendingorwearofthepumpshaft,damageorcorrosionoftheimpellervaneanddamageoragingofthewasher.Beforewerepairthewaterpump,pleasedocheckitstechnicalstatewiththeenginerunning.Themaindefectsoftheradiatorarein