1.1 本试验方法涵盖了用于评估汽车发动机油某些高温性能特性的发动机试验程序，包括机油增稠（通过运动粘度增加测量）、活塞沉积物、卡环、机油消耗和磷保持。这种油包括单粘度和多粘度级油，用于火花点火式汽油发动机和柴油发动机。 1.1.1 此外，根据非强制性补充要求，可以进行IIIHA序列试验（迷你旋转粘度计和冷起动模拟器测量）或IIIHB序列试验（磷保持率测量）。这些补充测试程序包含在 附录X1 和 附录X2 分别地 注1: SAE J304中讨论了用于评估发动机机油性能以满足规范要求的配套试验方法。 1.2 以国际单位制表示的数值应视为标准。本标准中不包括其他计量单位。 1.2.1、 例外情况: 1.2.1.1 如果没有直接的SI等效物，如螺纹、国家管道螺纹/直径、管道尺寸、阀门尺寸和弹簧。 1.2.1.2 环端间隙 表A8.7 ，中窜缸通风支架的尺寸 图A3.2 ，和中的扭矩扳手 表A8.1 以英寸磅为单位。 1.3 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的使用者有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 中提供了具体的警告声明 6.11.6 ， 7.1 ， 7.2.1 和 7.3 。 1.4 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 ====意义和用途====== 5.1 该试验方法旨在评估汽车发动机油在中等高速、高温条件下对机油增厚和活塞沉积物的保护作用。 5.1.1 油的运动粘度的增加表明油由于氧化而变稠的趋势。在汽车服务中，这种增稠可能会导致油泵不足，并导致灾难性的发动机故障。 5.1.2 机油的沉积物等级表示整个发动机中沉积物形成的趋势，包括可能导致活塞环卡在凹槽中的沉积物。在汽车维修中，这种卡环会导致发动机压缩压力的损失。 5.2 开发该测试方法是为了与已知良好和较差的油相关联，以防止油稠化和活塞沉积物。在本试验的开发过程中，还使用了使用无铅燃料产生不太理想结果的特殊配方油。 5.3 IIIH序列机油试验已被推荐作为IIIG序列试验的替代品，预计将用于发动机润滑油的规格和分类，例如: 5.3.1 规格 天4485 。 5.3.2 军用规范MIL-PRF-2104。 5.3.3 SAE分类J183。

1.1 This test method covers an engine test procedure for evaluating automotive engine oils for certain high-temperature performance characteristics, including oil thickening (as measured by kinematic viscosity increase), piston deposits, ring sticking, oil consumption, and phosphorus retention. Such oils include both single-viscosity and multiviscosity grade oils that are used in both spark-ignition, gasoline-fueled engines, as well as in diesel engines. 1.1.1 Additionally, with nonmandatory supplemental requirements, a Sequence IIIHA Test (Mini Rotary Viscometer and Cold Cranking Simulator measurements), or a Sequence IIIHB Test (phosphorus retention measurement) can be conducted. These supplemental test procedures are contained in Appendix X1 and Appendix X2 , respectively. Note 1: Companion test methods used to evaluate engine oil performance for specification requirements are discussed in SAE J304. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.2.1 Exceptions: 1.2.1.1 Where there is no direct SI equivalent such as screw threads, national pipe threads/diameters, tubing sizes, and valve sizes and springs. 1.2.1.2 The ring end gaps in Table A8.7 , the dimensions for the blowby ventilation support bracket in Fig. A3.2 , and the torque wrenches in Table A8.1 are in inch-pound units. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific warning statements are provided in 6.11.6 , 7.1 , 7.2.1 , and 7.3 . 1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 This test method was developed to evaluate automotive engine oils for protection against oil thickening and piston deposits during moderately high-speed, hightemperature service. 5.1.1 The increase in kinematic viscosity of the oil indicates the tendency of an oil to thicken because of oxidation. In automotive service, such thickening can cause oil pump starvation and resultant catastrophic engine failures. 5.1.2 The deposit ratings for an oil indicate the tendency for the formation of deposits throughout the engine, including those that can cause sticking of the piston rings in their grooves. In automotive service, such ring sticking can cause a loss of compression pressures in the engine. 5.2 The test method was developed to correlate with oils of known good and poor protection against oil thickening and piston deposits. Specially formulated oils that produce less than desirable results with unleaded fuels were also used during the development of this test. 5.3 The Sequence IIIH engine oil test has been recommended as a replacement for the Sequence IIIG test and is expected to be used in specifications and classifications of engine lubricating oils, such as the following: 5.3.1 Specification D4485 . 5.3.2 Military Specification MIL-PRF-2104. 5.3.3 SAE Classification J183.