离合器附件内容

1、Cooling-system Service and Maenance-A typical 4 cylinder vehicle cruising along the highway at around 50per hour,will produce 4000 controlled explos per minute inside theengine as the spark plugs ignite the fuel in each cylinder to propel thevehicle down the road.Obviously, these explos produce an e

2、normousamount of heat and, if not controlled, will destroy an engine in a matterof minutes. The pure of the cooling-system is to keep the engine at itsmost efficient operating temperature at all engine speeds and all drivingconditions. Cooling-system is responsible for the protection of the normalwo

3、rk of the engine sot the engine has a longer service life. In fact,the cooling system on a car driving down the freeway dissipates enoughheat to heat two average-sized houses!But automobile can withoutcooling-system .In other word, Cooling-system is very important for a automobile.Two general types

4、of cooling-system have been used on four-cycleautomotive engines,air cooling and liquid cooling.Most automotive enginesnow employ liquid cooling.The liquid cooling system consists ofwaterpumps,radiator,radiator cooling fans, thermosbypass system,freezeplugs,water jackets and so on.The cooling system

5、 is made up of thepassages inside the engine block and heads, awatump to circulate thecoolant, a thermosto control the temperature of the coolant, aradiator to cool the coolant, a radiator cap to control the prere inthe system, and some plumbing consisting oferconnecting hoses totransfer the coolant

6、 from the engine to radiator and also to the carsheater system where hot coolant is used to warm up the vehicleserioron a cold day.The modern cooling system has not changed much from the cooling systems inthe mbackhe 20s.Oh sure, ise infiniy morereliable and efficienng its job, but the basic cooling

7、 systemstill consists of liquid coolant being circulated through the engine, thenout to the radiator to be cooled by the air stream coming through thefront grill of the vehicle.Todays cooling system must maahe engineonstant temperature whether the outside air temperature is 110degrees Fahrenheitor 1

8、0 below zero.If the engine temperature is toolow, fuel economy will suffer and emiss will rise.If the temperatureis allowed to get too hot for too long, the engine will self destruct.The most important maenance item is to flush and refill the coolantperiodically.The reason for this important service

9、 ist anti-freezehas a number of additivest are designed to prevent corrohecooling system.This corrotends to accelerate when several differenttypes of metaleract with each other.The corrocauses scaleteventually builds up and begins to clog the thin flat tubesheradiator and heater core. causing the en

10、gine to eventually overheat.Theorrochemicalshe antifreeze prevents this, but they have alimited life span.Overriod of time,rust and scale restrict radiator and engine waterjackets;the rust and scale restrict the circulation of water,and theengine tends to over heart. In addition, the house and conne

11、ctions betthe radiator and the engine many deteriorate, causing leakage orninadetorted,many not close and open properly,thusg theeffectivenness of the cooling system. A number of tests of the mne thecondition of these parts. In addition,the strength of the antifreezesolution can be tests.The Nationa

12、l Automotive Radiator Service Assotion (NARSA)mendst motorists have a seven-poprevenive cooling system maenancecheckeast once every two years.The seven-poprogram isdesigned to identify any areast need attention. It consists of:belts and hosesa visual inspection of all cooling system components, incl

13、udinga radiator prere cap test to check for themended systemprere levela thermoscheck for proper opening and closinga prere test to identify any external leaks to the coolingsystem parts; including the radiator, watump, engine coolant passages,radiator and heater hoses and heater coreanernal leak te

14、st to check for combustion gas leakageothe cooling systeman engine fan test for proper operationa systemer flush and refill with car manufacturersVisual InspectionWhat you are looking for is the condition of the belts and hoses.Theradiator hoses and heater hoses are easily inspected just by opening

15、thehood and looking.You want to be suret the hoses have no cracking orsplitting andt there is no bulging or swelling ats.If thereis any sign of problems, the hose should be replaced with the correct partnumber for the year, make and mof the vehicle.Never use a universalhose unless it is an emergency

16、 and a proper molded hose is not available.Heater hoses are usually straight runs and are not molded, so a universalhose is fine to use and often is allt is available.Make suretyou use the proper inside diameter for the hose being replaced.Foreither the radiator hoses or the heater hoses, make suret

17、 you routethe replacement hosehe same wayt the original hose was running.ition the hose away from any obstructiont cansibly damage itand always use new hose cls.After you refill the cooling system withcoolant, do a prere test to make suret there are no leaks.On most older vehicles, the watump is dri

18、ven by a V belt or sentinebelt on the front of the enginet is also responsible for driving thealternator,er steering pump and air conditioner compressor.Thesetypes of belts are easy to inspect and replace if they are worn.You arelooking for dry cracking on the inside surface of the belt.On later veh

19、icles, the watump is often driven by the timing belt.This belt usually has a specific life expectancy at which time it must bereplaced to insuret it does not fail.Since the timing belt is insidethe engine and will require partial engine disassembly to inspect, it isvery important to replace ithe cor

20、recterval.Since the labor toreplace this belt can be significant, it is a good idea to replace thewatump at the same timet the belt is replaced.This is because 90percent of the labor to replace a watump has already been done toreplace the timing belt.It is simply good insurance to replace the pumpwh

21、ile everything is apart.Radiator prere cap testA radiator prere cap is designed to maain prerehe coolingsystemertaaximum prere.If the cooling system exceedstprere, a valvehe cap opens to bleed the exsive prereorethe reserve.Once the engine has cooled off, a negative prebegins to develophe cooling sy

22、stem.When this happens, a secondvalvehe cap allows the coolant to be sd backo the radiatorfrom the reserveoverheat.A pre.If the cap should fail, the engine can easilyre test of the radiator cap is a quick way tol ifthe cap isng its job.It should be able to hold its rated prerefor two minutes.Since r

23、adiator caps are quite inexpensive, I wouldmend replacing it every 3 years or 36,000, just for addedinsurance.Make absoluy suredesigned for your vehicle.t you replace it with onet isThermoscheck for proper opening and closingThis sts only nesystem.sary if you are having problems with the coolingA th

24、ermosis designed to openertain coolant temperature.Tohe engine, start the engine andteshermoswhile it is stilllet it come to normal operating temperature (do not let it overheat).Ifit takes an unusually long time for the engine to warm up or for theheater to begin delivering hot air, the thermosmay

25、be stuckheopenition.If the engine does warm up, shut it ond look for thetwo radiator hoses.These are the two large hosest go from the engineto the radiator.Feel them carefully (they could be very hot).If onehose is hot and the other is cold, the thermosmay be stuck closed.If you are having problems

26、andthe thermos, remove it and placeit in a pot of water.Bring the water to a boil and watch the thermos.You should see it open when the water reaches a boil.Most thermossopen at about 195 degrees Fahrenheit.An oven thermometerhe watershould confirmt the thermosis working properly.PrePrere test to id

27、entify any external leaksre testing the cooling system is a simple pros to determine wherea leak is located.Thisonly performed after the cooling systemhas cooled sufficiently to allow you to safely remove the prere cap.Once you are suret the cooling system is full of coolant, a coolingsystem prere t

28、ester is attached in place of the radiator cap.Thetester isn pumped to build up prerehe system.There is agauge on the tester indicating how much prere is being pumped.Youshould pump it to the premanufacturers specs.re indicated on the prere cap or toOnce prere is appd, you can bego look for leaks.Al

29、so watch thegauge on the tester to see if it loses prere.If the prere dropsmoren a couple of poundswo minutes, there is likely a leaksomewheret may be hidden.It is not always easy to see where a leakis originating from.It is best to have the vehicle up on a lift so youcan look over everything wishop

30、 light or fl shli ht.If the heatercore in leaking, it may not be visible since the core is enclosed and notvisible without major disassembly, but one sure sign is the unmistakable odor of antifreeze inside the car.You may also notice the windshielding up win oily residue.ernal leak testIf you are lo

31、sing coolant, but there are no signs of leaks, you could have a blown head gasket.The best way to test for this problem is wicombustion leak test on the radiator.This isplished using a blocktester.This is a kitt performs a chemical test on the vaporsheradiator.Blue tester fluid is added to the plast

32、ic container on thetester.If the fluid turns yellow during the test, then exhaust gassesare presenthe radiator.The most common causes for exhaust gasses to be presenthe radiator isa blown head gasket.Replacing a bad head gasket requires a majordisassembly of the engine and can be quite expensive.Oth

33、er causesinclude a cracked head or a cracked block, bore even more undesirablen having to replace a head gasket.When a head gasket goes badThe pros of replacing a head gasket begins with compley draining thecoolant from the engine.The top part of the engine is then disassembledalong with much of the

34、 front of the engine in order to gain acs to thecylinder heads.The head or heads are then removed and a thoroughinspection for additional damage is done.Before the engine can be reassembled, the mating surfaof the head andblock arecleaned to make suret nothing willerfere with thesealing properties o

35、f the gasket.The surface of the cylinder head isalso checked for flatness and, in some cases, the block is checked aswell.The head gasket is thenitioned on the block and aligned usinglocator pegst are builto the block.The head is then placed ontop of the gasket and a number of bolts, called head-bol

36、ts are coated withoil and loosely threadedo the assembly.The bolts are then tightenedin a specific order to a specified initial torque using a spel wrenchcalled a torque wrench.This is to insuret the head gasket is crushedevenly in order to insure a tight seal.This pros is then repeated toa second,

37、tighter torque setting, then finally a third torque setting.Atthis p, the rest of the engi e is rssland the cooling systemis filled wimixture of antifreeze and water.Once the engine isfilled, the technin will prethere are no leaks.re test the cooling system to make sureany engines, coolant also pass

38、es betn the heads and theakemanifold.There are also gaskets for theake manifold to keep thecoolant from leaking ougasket is a much easier job couple of hours or more fort po.Replacing anake manifoldn a head gasket, bt job.an still take aEngine Fan TestThe radiator cooling fan is an important part of

39、 the cooling system operation.While a fan is not really needed while a vehicle is travelingdown the highway, it is extremely important when driving slowly or stoppedwith the engine running.he past, the fan was attached to the engineand was driven by the fan belt.The speed of the fan was directlyprop

40、ortional to the speed of the engine.This type of system sometimescaused exsive noise as the car accelerated through the gears.As theengine sped up, a rushing fan noise could be heard.To quiet things downand place less of a draghe engine, a viscous fan drive was developedin order to disengage the fan

41、 when it was not needed.When computer controls cameo being, these engine driven fans gave wayto electric fanst were mounted directly on the radiator.Atemperature sensor determined when the engine was beginning to run too hotand turned on the fan to draw air through the radiator to cool the engine.On

42、 many cars, there were two fans mounted side by side to make suretthe radiator had a uniform air flow for the width of the unit.When the car wasotion, the speed of the air entering the grill wassufficient to keep the coolanthe proper temperature, so the fans wereshut off.When the vehicle came to a s

43、top, there was no natural air flow,so the fan would come on as soon as the engine reached a certaintemperature.If the air conditioner was turned on, a different circuit would comeoplay.The reason for this is the air conditioning system always requiresa good air flow through the condenser mounted in

44、front of the radiator.If the air flow stopped, the air conditioned air coming through the dash outlets would immediay start warming up.For this reason, when the airconditioner is turned on, the fan circuit woulder the fans regardlessof engine temperature.If you noticet the engine temperature begins

45、rising soon after thevehicle comes to a stop, thething to check is fan operation.Ifthe fan is not turning when the engine is hot, a simpleto turnthe AC on.If the fan begins to work,the temperature sensor inthe fan circuit (you will need a wiring diagram for your vehicle to findit).In order to test t

46、he fan motor itself, unplug the two wire connector to the fan and connect a 12 volt source to one terminal and ground theother. (it doesnt matter which is which for this test)If the fan motorbegins to turn, the motor is good.If it doesnt turn, the motor is bad and must be replaced.In order to test t

47、he system further, you will need a repair manual for theyear, make and mvehicle and follow the troubleshooting charts anddiagnostic procedures for your vehicle.On most systems, there will be afan relay or fan control modulet can be a trouble spot.There are anumber of different control systems, each

48、requiring a different testprocedure.Without the proper repair information, you can easily do moreharmn good.Cooling systemer flush and refillWhile you can replace old coolant by draining it out and replacing it withfresh coolant, the best way to properly maain your cooling system is tohave the syste

49、mer flushed.er flushing will remove all the oldcoolant and pull out any sediment and scale along with it.er flushing requires a spel machinet many auto repair shops havefor the pure.The procedure requirest the thermosis removed,the lower radiator hose is disconnected, and the flush machine isconnect

50、ed in line.The lower hose is connected to the machine and theother hose from the machine is connected to the radiator where the lowerhose was disconnected from.Water, and sometimes, a cleaning agent is pumped through the coolingsystem in a reverse path from the normal coolant flow.This allows anysca

51、le to be loosened and flow out.Once clear water is coming out of thesystem, the hose is reconnected and a new thermosis installed.Thenthe cooling system is refilled with the appropriate amount of antifreezeto bring the coolant to the proper mixture of antifreeze and water.For most vehicles and most

52、climates, the mixture is 50 percent antifreeze and50 percent water.In colder climates, more antifreeze is used, but mustnever exceed 75 percent antifreeze.Check your owners manual for theproprocedures andmendations for your vehicle.The cooling system should be cleaned at periodicervals to prevent th

53、eaccumulation of exsive rusts and scale.Accumulated rust and scale canbe loosened by a good cleaning compound.There are various types ofcleaning compounds;all must be used carefully in acordance with themanufacturers instructions.冷却系统的维修与一个典型的四缸汽车在高速公以约 50 英里每小时的速度行驶，在火花塞在各缸内点燃些推进汽车行驶过程中，发内每分钟将产生 40

54、00 卡的能量。显然,这产生巨大的的热量,如果不加控制,将会很快就摧毁发。冷却系统的目的是为了保持发在各种速度和操作条件下能以最有效的工作温度。冷却系统负责保护发的正常工作，使发使用延长。事实上,一辆汽车在高速公行驶时，冷却系统散发的热量足以给两个普通尺寸的房子供暖!但是汽车不能没有冷却系统,换句话说，冷却系统对于汽车是非常重要的。空冷和液冷两种类型的冷却系统已经被用于四冲程的汽车发中。大多数的汽车发现在使用液体冷却，液冷系统由水泵、散热器、冷却风扇,支路恒温系统、冷冻塞、水外套等等组成。冷却系统由位于发缸体和发罩的通道，循环冷却液的水泵，控制冷却液温度的恒温器，降低冷却液温度的散热器以及控制

55、系统压力的散热器盖和一些管体组成。这些管体是用来从发传送冷却液到散热器和汽车热系统去的，保证了在寒冷的天气汽车的温度。20 世纪以来，冷却系统用在发上后，它没有改变太多。哦,当然,虽然冷却系统在工作中变得更为可靠和有效，但是基本的冷却系统仍然由冷却液组成。这些冷却液通过发进行循环，然后流通到外面的散热器，由通过汽车前格栅流入的空气进行冷却。现今的冷却系统必须保持发温度恒定，不管外面的温度是 110 华氏度或 10 零度以下。如果发温度过低、经济性将受损和排放率将会上升。如果温度持续过热,发将自我破坏。最重要的维修项目是冷却液的定期充满和替换。这个重要的原因是冷却剂中有许多添加剂,用于防止腐蚀冷

56、却系统。在几种不同类型的金属相互作用时，这种腐蚀速度加速。规模的腐蚀最后建立并开始堵塞散热器、加热器的薄平管,最终导致发过热。这些在冷却剂中的防腐剂能防止这种情况的发生，但是他们有有限的。经过一段时间后，锈和氧化皮限制了散热器和发的水外套，限制了水的循环，从而使发过热，此外，汽缸和散热器与发之间的连接器极度，导致燃气，很多关闭不严或开启不恰当，从而降低了冷却系统的有效性。一些公司对这些条件进行了一系列的实验，此外，防冻剂的长处的解决方案也可以测试。汽车散热器服务(NARSA)建议，有七点要注意预防的东西去冷却系统，至少每两年检查一次。这七点旨在提醒确定任何部位都需要关注。它包括:1、目视检查所

57、有的冷却系统的组成部分,包括皮带和软管2、散热器及压盖检查以的系统压力水平3、检查温控器适当的开启和关闭4、压力测试,以确定所有对外冷却系统的无泄漏,包括散热器、水泵、发动机冷却通道,加热器软管和加热器的5、泄漏测试来检查燃气是否泄漏到冷却系统6、发和风机测试正常工作7、系统能源的充满和替换。1、目视检查要是你想要检查皮带和软管部分，那么散热器软管和加热器软管是很容易检查的，仅仅只需要打开盖子然后检查就可以了。你应该确保水管无开裂或和无胀形或肿胀。如果有出现问题的迹象,软管应该立即更换。不同型号，不同年份产的汽车的软管是不一样的，不能通用，除非在紧急条件和原来的软管不可使用的条件下方可使用，否

58、则会发生预想不到的。确保你替换的软管符合正确的内径，不管是散热器软管或加热管,确保你更换软管的路线与原来软管的部位一样。软管安装在远离任何可能损害到它的位置上，而管夹总是使用新的。之后,你再对冷却系统的冷却剂做一个压力测试以确保没有泄漏。在大多数老旧的车辆上，水泵端由一个V 形皮带或蛇形皮带驱动,还负责推动发电机、动力转向泵、空调压缩机。如果他们都磨损了，这些不同类型的皮带是容易检查和更换的。在后来的车辆上，水泵通常是由正时皮带驱动。这个皮带通常会有特定的，超过此期间必须更换,以确保它没有损坏。因为正时皮带位于发，则检查时需将发部分拆卸，替换时将它安装在正确的间隙这是很重要的。人类用别的东西取

59、代正时皮带有了显著意义，取代了带的同时取代了水泵。这是因为 90%的工作来完成一个水泵的取代时，正时皮带已经更换。当所有东西都分开的时候，它更安全的替换了泵。2、散热器压盖压力测试散热器压盖设计的目的是为了保持冷却系统中的压力处在一个合适的最大压力，如果冷却系统的压力超过了阀门的压力,阀门顶开，冷却液到油箱中，一旦发冷却下来,在冷却系统中将产生一个负压力。产生这种情况的时候，压盖上的第二个阀将冷却剂从油箱吸收到散热器中，如果没有设计这个压盖，那么发很容易产生过热。散热器压盖压力测试是一个快速的方法来判断压盖是否正在正确运转。它应该能够保持其额定压力两分钟。散热器盖是相当便宜的，我建议每 3 年

60、或每运行 36,000 公里更换一次,就当作一份额外的保险，应保证你专为你的车放一个预备。3、检查调温器适当的开启和关闭这一步是只有当你的冷却系统出现问题的时候才是必要的。恒温器的设计是用来使冷却液的温度处于一个合适的温度。启动发，让发处在一个正常的工作温度（不要让它过热），调温器在发时进试，如果它需要较长时间才能让发暖和起来或者加热器开始送热风，那么调温器开关可能被卡在了。如果发已经暖和了,把它关掉,寻找两个散热器软管。这两条软管是从发连接到散热器的。地触碰它们（它们可能会很热）如果一个软管是热的,另一个是冷的,温控器可能被卡住。如果你怀疑温控器有问题,把它放在一壶水里，把水加热沸腾并且看温