Skripsi ini bertujuan untuk mendapatkan solusi dan alternatif perbaikan masalah kasus repair engine dikarenakan terjadinya gangguan pada putaran pompa oli yang akan berdampak pada temperatur mesin motor yang panas (over heat) yang bisa menyebabkan kerusakan pada komponen part engine lainnya. Metode yang digunakan digunakan adalah Six Sigma yang terdiri dari tahapan Define, Measure, Analyze, Improve, Control (DMAIC). Aktivitas yang dilakukan pada tahap define adalah identifikasi masalah, menetukan Critical To Quality (CTQ), Logic Tree Diagram, SIPOC diagram. Tahap measure melakukan pemetaan proses, pengukuran terhadap kemampuan proses (Cp). Tahap analyze melakukan analisa terhadap kemungkinan-kemungkinan yang menyebabkan masalah dengan diagram tulang ikan (sebab akibat), Failure Tree Analysis (FTA) dan Failure Mode Effect and Analysis (FMEA). Tahap improve melakukan perbaikan dari hasil-hasil analisa penyebab masalah. Tahap control melakukan monitoring terhadap perbaikan-perbaikan yang telah dilakukan, dengan menggunakan Statistical Process Control (SPC). Dari tahapan perbaikan diatas didapatkan faktor yang mempengaruhi terjadinya ganguan pada putaran pompa olir adalah adanya penyimpangan pada concentricity spindle cam chain dan juga cacat pada permukaan diameter 8 dan 9 dari spindle. Berdasarkan tahap perbaikan yang dilakukan, metode six sigma sangat efektif dalam menyelesaikan masalah diatas ini diidentifikasikan dengan naiknya nilai indeks kemampuan proses (Cp), menurunnya angka kegagalan proses dalam Part Per Million (PPM) dan naiknya nilai sigma level.

---

The purpose of this final project is to get the solution and the alternative corrective actions on repair engine claim's that cause of problem in oil pump wheeling. This problem has negative effects on engine temperature (engine over heat) that can appear damaged to the other engine component. The method used in analyzing and solving the problem is Six Sigma, which includes the phases of Define, Measure, Analyze, Improve, Control (DMAIC). The activities on Define phase are problem identification, Critical to Quality decision making,logic Tree Diagram and SIPOC Diagram formulation. The next step is Measure phase, hich involves the activities of process mapping and Capability Process Index (Cp) measurement. The third step is Analyze phase. The activities done on this step are potential problem analysis using Fishbone diagram (cause and effect diagram), Failure Tree Analysis (FTA) and Failure Mode Effect and Analysis (FMEA). The phase is followed by Improve phase, including the activities of corrective action execution on the basis of potential problem analysis done on prior step. The final step is Activity Control phase; that is performing the monitoring action to the improvement outcome, using Statistical Process Control (SPC).

The conclusion obtained from doing those former activities is that the factors causing the stucked oil pump wheeling problem are concentricity of spindle cam chain out of specification and scrath on the surface diameter 8 and 9 spindle cam chain. Due to the completion of problem identification and corrective action, it can be concluded that six sigma method is very effective on problem solving. It is indicated by the increase of capability index value (Cp), the decrease of defect process index value in parts per million (PPM) and the increase of sigma level value.