外文翻译--润滑系统维修.doc

Chapter 18 Lubrication System Service CHAPTER PREVIEW 　　If the lubrication system becomes contaminated with dirt or if it stops operating properly,the engine may be damaged in a very short time .A mechanic must be able to troubleshoot a malfunction in the system and perform preventive maintaince to prevent a failure in the system. The troubleshooting and preventive maintenance operations are presented in this chapter along with the major service procedures for each of the components in the lubrication system. 18.1 TROBLESHOOTING 　　The first sign of a lubrication system problem is usually that the oil pressure warning light comes on,indicating low oil pressure in the engine. 18.2 Checking the oil and the Gauge 　　The first thing the mechanic should do is make sure that the engine has the proper amount o f oil. If oil level is too low,there is not enough oil flow for proper lubration. 　　 When there is enough oil in the engine and the warning light continues to burn,find out whether the problem is really low oil pressure or just a malfunction in the electrical warning circuit.The quickest way to do this is to install a test pressure gauge,operate the engine,and accurately measure the oil pressure.Oil pressure test gauges are available that will read pressures of 0 to 100 psi(0 to 690 kpa or so). Remove the sending unit for the oil pressure warning light and install a hose for the oil pressure test gauge in its place.Connect the oil pressure gauge to the hose and start the engine.If the gauge shows no oil pressure,stop the engine to prevent further damage.If the gauge shows there is oil pressure ,operate the engine at several different speeds and note the oil pressure.Compare these readings with specifications in the manufactures service manual. 18.3 Using a Prelubricator 　　Low oil pressre may be caused by wear or damage to interal engine components.It may be due to a problem in the lubrication system.If o