The paper reports the results of an experimental investi-gation on the effect of some climatic factors on oil consumption rates. Worn compression rings having a profile of super ellipse, high cooling temperatures and contaminated lubricants were considered in the study. The testing program was achieved on an EMSON AVI single cylinder diesel engine with a complete set of control and measuring devices. Different wear indices for the compression rings were investigated over the mechanicl and running conditions range of the tested engine. Three oils with different iron and dust contents were tested. Optimal oil consumption rates have been observed for worn ring shapes and which can be proposed for actual automotive engines. The interaction between oil contamination ratios and cooling temperature have been examined and reported.