Meaning and use
4.1 Engine coolant is required to prevent heat transfer corrosion of aluminum cylinder heads during engine operation. Any corrosion products that form may be deposited on the internal surface of the radiator, reducing the heat transfer efficiency of the radiator. Overheating and boiling of the cooling system may then occur.

4.2 This test method provides a way to selectively screen unused engine coolants and easily distinguish those that are not suitable for use with an aluminum cylinder head engine. However, in this test method, the satisfactory performance of the coolant does not ensure adequate long-term performance. In addition, a more comprehensive evaluation should be conducted using simulation services, dynamometers, and vehicle testing to determine the long-term effectiveness of the coolant.

ASTM D4340-2019 “Corrosion of Engine Coolant on Cast Aluminum Alloys under Heat Removal Conditions”

Radius
1.1 This test method covers laboratory screening procedures for evaluating the effectiveness of engine coolants against corrosion of aluminum cast alloys under the heat transfer conditions that may exist in an aluminum cylinder head engine.

1.2 Values expressed in SI units shall be regarded as standard values. The values given in parentheses after the SI unit are for reference only and are not considered standard values.

1.3 This standard is not intended to address all safety concerns, if any, associated with its use. It is the responsibility of users of this standard to establish appropriate safety, health and environmental practices and to determine the applicability of regulatory restrictions prior to use. Specific precautions are given in sections 11 and 12.

1.4 This international standard is based on internationally recognized standardization principles established in the Decision on Principles for the Development of International Standards, Guidelines and Recommendations issued by the WTO Committee on Technical Barriers to Trade.