Korelasi Kandungan Unsur Logam Dengan Angka Basa Total Pada Pelumas Enduro Berdasarkan Jarak Tempuh Sepeda Motor

Abstract

Pelumas berperan penting dalam menjaga kinerja mesin, tetapi kualitasnya menurun selama pemakaian akibat oksidasi, konsumsi aditif, dan kontaminasi logam. Penelitian ini bertujuan menentukan karakteristik kualitas pelumas Enduro Matic-V SAE 10W-40 dan Enduro Racing SAE 10W-40 pada kondisi fresh oil dan used oil, serta menganalisis hubungan Total Base Number (TBN) dengan kandungan unsur logam berdasarkan variasi jarak tempuh. Analisis dilakukan menggunakan metode ASTM melalui ICP-OES, TBN, FTIR dan viskositas kinematik pada sampel fresh oil, 250 km, 500 km, dan 1000 km dengan tujuh kali ulangan, kemudian dianalisis menggunakan korelasi pearson dan ANOVA. Nilai TBN menurun seiring bertambahnya jarak tempuh dan diikuti perubahan logam aditif maupun kontaminan. Ca dan Zn berkolerasi signifikan terhadap TBN (p<0,05), sedangkan Cu, Fe, Si, dan Na umumnya tidak signifikan (p>0,05). Peningkatan parameter jelaga, oksidasi, nitrasi, sulfasi, dan air serta perubahan viskositas menunjukkan penurunan kualitas pelumas dan ketahanan aditif.

Lubricants play an important role in maintaining engine performance; however, their quality deteriorates during service due to oxidation, additive depletion, and metal contamination. This study aimed to determine the quality characteristics of Enduro Matic-V SAE 10W-40 and Enduro Racing SAE 10W-40 lubricants under fresh oil and used oil conditions, and to analyze the relationship between the Total Base Number (TBN) and metal element content based on mileage variations. Analyses were conducted according to ASTM methods using ICP-OES, TBN determination, FTIR, and kinematic viscosity testing on fresh oil samples and used oil samples collected at 250 km, 500 km, and 1000 km, with seven replications for each condition. The data were subsequently analyzed using Pearson correlation and ANOVA. TBN values decreased with increasing mileage and were accompanied by changes in both additive and contaminant metal contents. Calcium (Ca) and zinc (Zn) showed significant correlations with TBN (p<0.05), whereas copper (Cu), iron (Fe), silicon (Si), and sodium (Na) generally showed no significant correlations (p>0.05). Increases in oxidation, soot, nitration, sulfation, and water parameters, together with changes in viscosity, indicated a decline in lubricant quality and additive durability.