1、Designation: D 4858 02An American National StandardStandard Test Method forDetermination of the Tendency of Lubricants to PromotePreignition in Two-Stroke-Cycle Gasoline Engines1This standard is issued under the fixed designation D 4858; the number immediately following the designation indicates the
2、 year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Dep
3、artment of Defense.1. Scope1.1 This test method2evaluates the performance of lubri-cants intended for use in two-stroke-cycle spark-ignition gaso-line engines which are prone to preignition.1.2 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It i
4、s theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.1.3 The values stated in SI units are the standard. The valuesgiven in parentheses are provided for information only.2. Refer
5、enced Documents2.1 ASTM Standards:B 152 Specification for Copper Sheet, Strip, Plate, andRolled Bar3D 439 Specification for Automotive Gasoline4D 445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids (and the Calculation of DynamicViscosity)4D 664 Test Method for Acid Number of Pe
6、troleum Productsby Potentiometric Titration4D 874 Test Method for Sulfated Ash from Lubricating Oilsand Additives4D 910 Specification for Aviation Gasolines4D 2270 Practice for Calculating Viscosity Index from Kine-matic Viscosity at 40 and 100C4D 2699 Test Method for Research Octane Number ofSpark-
7、Ignition Engine Fuel4D 2700 Test Method for Motor Octane Number of Spark-Ignition Engine Fuel4D 2885 Test Method for Research and Motor Method Oc-tane Ratings Using On-Line Analyzers4D 2896 Test Method for Base Number of Petroleum Prod-ucts by Potentiometric Perchloric Acid Titration4D 4857 Test Met
8、hod for Determination of the Ability ofLubricants to Minimize Ring Sticking and Piston Depositsin Two-Stroke-Cycle Gasoline Engines Other than Out-boards5D 4863 Test Method for Determination of Lubricity ofTwo-Stroke-Cycle Gasoline Engine Lubricants5E 230 Specification and Temperature-Electromotive
9、Force(EMF) Tables for Standardized Thermocouples62.2 ANSI Standard:ANSI MC 96.1 American National Standard for Tempera-ture Measurement Thermocouples73. Terminology3.1 Definitions:3.1.1 combustion chamberin reciprocating internal com-bustion engines, the volume bounded by the piston crown andany por
10、tion of the cylinder walls extending above the pistoncrown when in the top dead center position, and the innersurface of the cylinder head including any spark plugs andother inserted components.3.1.2 preignitionin a spark-ignition engine, ignition ofthe mixture of fuel and air in the combustion cham
11、ber beforethe passage of the spark.3.1.3 scuff, scuffngin lubrication, damage caused byinstantaneous localized welding between surfaces in relativemotion that does not result in immobilization of the parts.D 48633.1.4 spark plug foulingdeposition of essentially noncon-ducting material onto the elect
12、rodes of a spark plug that may,but will not necessarily, prevent the plug from operating.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.B0 on Automotive Lubricants.Current edition approved Nov.
13、 10, 2002. Published January 2003. Originallyapproved in 1988. Last previous edition approved in 2000 as D 485800.2Until the next revision of this test method, the ASTM Test Monitoring Centerwill update changes in this test method by means of Information Letters. These canbe obtained from the ASTM T
14、est Monitoring Center, 6555 Penn Ave., Pittsburgh, PA15206-4489. Attention: Administrator. This edition incorporates revisions in allInformation Letters through No. 013.3Annual Book of ASTM Standards, Vol 02.01.4Annual Book of ASTM Standards, Vol 05.01.5Annual Book of ASTM Standards, Vol 05.02.6Annu
15、al Book of ASTM Standards, Vol 14.03.7Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.D 48573.1.5 spark plug whiskering, also s
16、park plug bridgingadeposit of conductive material on the spark plug electrodeswhich tends to form a bridge between them, thus shorting outthe plug. D 48573.2 Definitions of Terms Specific to This Standard:3.2.1 major preignitionpreignition that causes a tempera-ture increase of 10C (18F) or more mea
17、sured at the innersurface of the cylinder head.3.2.2 minor preignitionpreignition that causes a tempera-ture increase of more than 7C (13F) and less than 10C(18F) measured at the inner surface of the cylinder head.4. Summary of Test Method4.1 The test is run in a 49 cm3single-cylinder air-cooledengi
18、ne operated under the conditions required by the specifi-cation against which it is being run. These are typically 4000r/min wide open throttle (WOT) using a 20:1 ratio of gasolineto oil by volume for a minimum of 50 h. The number ofincidences of preignition, as indicated by a rapid increase incombu
19、stion chamber temperature, is recorded.NOTE 1Pass-Fail CriterionThe number of occurrences of preigni-tion during the test of a candidate oil shall not exceed that permitted by thespecification against which it is run.5. Significance and Use5.1 Two-stroke-cycle gasoline engines are generally morepron
20、e to preignition than are four-stroke-cycle engines due tothe absence of the internal cooling that takes place during theinduction stroke of the four-stroke-cycle engines. Preignitioncan lead to major piston damage, either directly due tolocalized overheating or as the result of preignition-inducedd
21、etonation. Some lubricant additives that are widely used infour-stroke-cycle gasoline engine oils are known to increasethe probability of preignition in gasoline two-stroke-cycleengines. This procedure is used to determine the tendency of anoil to induce preignition in both water-cooled and air-cool
22、edtwo-stroke-cycle gasoline engines.6. Apparatus6.1 Test Engine and Stand:6.1.1 Test Engine ConfigurationA Yamaha CE-50 49 cm3loop-scavenged air-cooled two-stroke-cycle engine is used.8This has 40 mm (1.57 in.) bore, 39.2 mm (1.54 in.) stroke, withan aluminum piston operating in a cast iron cylinder
23、 bore. Thecylinder head is removable, with a hemispherical combustionchamber. For the purposes of this test the head shall bemodified as specified in 6.3.1.1. Further details are given inAnnex A1.NOTE 2The engine designation normally includes a final letterindicating the model, such as CE-50S, the m
24、odel on which this test wasdeveloped. If this model is not available check the suitability for this testof available models with the manufacturer.86.1.2 Test StandThe dynamometer shall be able to absorb2.5 kW (3.4 hp) at 4000 to 6000 r/min with an inherent torquemeasurement accuracy of 60.5 % or bet
25、ter, and be capable ofmaintaining 4000 6 30 r/min with varying power input. Adirect shaft drive or a belt drive from the engine crankshaftmay be used. A complete test stand assembly, as shown in Fig.1, is available.96.1.3 Cooling BlowerThe original internal engine fanshall be removed or have its bla
26、des machined off. A variabledelivery blower with a free flow capacity of about 34 m3/min(1200 ft3/min) of air is recommended. The flow from theblower shall be directed toward the intake side of the engine. Asuitable arrangement is shown in Fig. 1.6.1.4 Fuel SystemFuel delivery pressure shall be main
27、-tained at 19 to 21 kPa (2.7 to 3.0 lb/in.2). The temperature ofthe fuel entering the carburetor shall not exceed 25C (77F),and this may require cooling in hot climates.6.2 Instrumentation:8The sole source of supply of the apparatus known to the committee at this timeis Engineering and Service Dept.
28、, Yamaha International Corp., P.O. Box 6555,Cypress, CA 90630. Parts, but not complete engines, may be obtained from Yamahamotorcycle dealers. If you are aware of alternative suppliers, please provide thisinformation to ASTM International Headquarters. Your comments will receivecareful consideration
29、 at a meeting of the responsible technical committee1, whichyou may attend.9Order from Southwest Research Institute, Automotive Products and EmissionsResearch Division, 6220 Culebra Rd., San Antonio, TX 78238.FIG. 1 Test StandD48580226.2.1 TachometerAn electronic tachometer accurate to 625 r/min.6.2
30、.2 Measurement of Ambient Conditions6.2.2 is writtenon the assumption that the engine draws ambient air from thetest room. If it is supplied with air from a controlled source,references to ambient temperature, pressure and humidityapply to the air from the controlled source.6.2.2.1 TemperatureA ther
31、mocouple or thermometer shallbe provided to read air temperature in the range 10 to 50C (50to 120F).6.2.2.2 Barometric PressureA barometer recording thepressure in the test room is required.6.2.2.3 HumidityA hygrometer or a wet and dry bulbthermometer is also required.6.2.2.4 RecorderContinuous reco
32、rding of the ambientconditions is recommended.6.2.3 CalibrationCalibrate the tachometer, ambient tem-perature, and pressure measurement devices every 90 days.The calibration standard shall be traceable to NIST.6.3 Engine and System Temperatures:6.3.1 Combustion Chamber Temperature:6.3.1.1 Modificati
33、on of Cylinder HeadThe cylinder headshall be fitted with a shielded thermocouple. A thermocouple ofthe iron-constantan type meeting the requirements of ANSI91.6 Type J (summarized very briefly in Specification E 230) isrecommended, but any thermocouple capable of performingsatisfactorily under the c
34、onditions of the test can be used.10Thegeneral dimensions and machining requirements are shown inFig. 2. The through hole, in which the thermocouple is requiredto fit closely, is about 3-mm (0.12-in.) diameter, and thecounterbore shall not extend closer than 4 mm (0.16 in.) to thecombustion chamber
35、surface. The dimensions of the counter-bore and thread are not critical, being suitable to availablethermocouples, but the thread diameter shall be less than 14mm (0.55 in.). A18 27-NPTF thread is recommended. Thethermocouple shall be made so that the last 3 to 4 mm (0.12 to0.16 in.) of its tip is a
36、 snug fit into the 3-mm diameter portionof the hole, and be mounted in the head so that its tip protrudessufficiently to allow it to be ground flush with the internalsurface of the head without penetrating the shield. When a headhas been newly fitted with a thermocouple, run a break-in inaccordance
37、with 10.2 and Table 1. The thermocouple readingnormally requires about 90 min to stabilize.6.3.1.2 Shutdown ProvisionProvision shall be made forshutdown of the engine in the case of a rapid (1 min or less)combustion chamber temperature increase of 10C (18F) ormore. This normally indicates an inciden
38、ce of major preigni-tion, and is required to minimize the risk of damage to theengine. An automatic shut down when such an increase isexperienced is recommended. At the least an alarm shall beprovided to operate after a temperature increase of 6 to 7C (11to 13F) to allow manual shut down by the oper
39、ator if the 10Climit is exceeded.6.3.2 Exhaust TemperatureA thermocouple is required inthe exhaust elbow within about 65 mm (2.5 in.) of the cylinderexhaust port to monitor exhaust temperature.9The thermo-couple junction shall be located within 63 mm (0.12 in.) of thecenter of the pipe.6.3.3 Spark P
40、lug Gasket TemperatureThe spark pluggasket may be fitted with one or two thermocouples, thenumber depending on the instrumentation used. A design thathas been found satisfactory is described in Appendix X1.116.3.4 Combustion Chamber and Spark Plug Gasket Tem-perature RecordersThese temperatures shal
41、l be recordedusing a system capable of storing the data for later retrieval.Maximum interval between successive recordings of the com-bustion chamber temperature is 2 s. A system with a range from40 to 750C (100 to 1400F) and an overall accuracy of 62C(4F) is suitable.6.3.5 CalibrationCalibrate the
42、combustion chamber, ex-haust and spark plug gasket temperature measurement devicesevery 90 days. The calibration standard shall be traceable toNIST.6.4 Fuel System:6.4.1 Flow MeterAny type accurate to 60.01 kg/h(60.02 lb/h) at about 1 kg/h (2 lb/h) flow rate may be used.Instruments measuring mass di
43、rectly are preferred. If a volu-metric measurement meter is used the temperature-densityrelationship shall be determined over the operating range forthe actual fuel-non-reference oil mixture used for use involume-mass conversion.10A suitable instrument is available from Omega Engineering Inc., P.O.
44、Box4047, One Omega Dr., Stanford, CT 06907.11A thermocouple basket that has been found satisfactory may be obtained fromLewis Engineering, 238-T Water St., Naugatuck, CT 06770.FIG. 2 Machining of Cylinder HeadD48580236.4.2 A temperature measuring device reading to at least40C (100F) to an accuracy o
45、f 61C (2F) and a pressuregage or transducer reading up to about 35 kPa (5 lbf/in.2)toanaccuracy of 62% are required to monitor the temperature andpressure of the fuel entering the carburetor.7. Materials and Reagents7.1 Test FuelThe test fuel shall be a leaded gasolineconsisting essentially of hydro
46、carbons, except for conventionallead antiknock, anticorrosion, anti-icing, etc. additives innormal concentration, and containing no non-lead metallicantiknock compounds or oxygenated blending compoundssuch as alcohols or ethers. It shall contain 0.4 to 0.6 g/L (1.5 to2.2 g/gal) of lead as lead alkyl
47、s with conventional motor mix oraviation mix scavengers, and shall have a minimum motoroctane number of 83, a maximum sensitivity (research octanenumber minus motor number) of 12 as determined by TestMethods D 2699, D 2700, or D 2885, as applicable, and shallotherwise meet the requirements of Specif
48、ication D 439 vola-tility grade A or B. Aviation gasoline meeting these require-ments and otherwise conforming to Specification D 910 Grade100 or 100LL may be used. Fuel from the same batch shall beused for calibration running and for any other tests referencedto that calibration. About 40 L (10 gal
49、) of fuel are required fora test, plus 12 L (3 gal) for the break-in.7.2 Reference OilsASTM 601 and 605 reference oils areused for calibration purposes.12ASTM 600 reference oil isused for break-in and as an assembly lubricant.12About 4 L (1gal) of reference oil is required to run a calibration test, and 0.4L (0.1 gal) of 600 for a break-in. The properties of these oils aresummarized in Annex A2.7.3 Non-Reference OilAbout 4 L (1 gal) are required fora 50 h test, varying according to the number of test hoursspecified. It is recomm
