PURPOSE: To impart long-term rust preventing property and to decrease a degreasing process by dissolving specified amts. of an amine compsn. of a specified compsn., morpholines, dicyclohexylamine and sulfonate in the base oil.

CONSTITUTION: This volatile rust preventive oil is prepared by dissolving the following components in the base oil. (A) 1-5wt.% of an amine compsn. containing 10-50 pts.wt. ethanolamine to 100 pts.wt. of carboxylic acid amine salt. (B) 1-30wt.% of morpholines, (C) 1-30wt.% of dicyclohexylamine, and (D) 1-40wt.% of sulfonate. Thereby, the obtd. oil can be used for rust preventing treatment on knocking-down parts of a car.