Standard Test Method for Evaluation of Automotive Engine Oils in the Sequence IIIH, Spark-Ignition Engine

Importancia y uso:

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.

Subcomité:

D02.B0

Referida por:

D4485-24

Volúmen:

05.04

Número ICS:

75.100 (Lubricants, industrial oils and related products)