As part of engineering projects, turnaround maintenance (TAM) projects also still suffer the issue of reusing knowledge across projects. Although TAM projects have a recurring character, the TAM projects’ schedule performance is still frequently unmet. It is also revealed that rework is one of the causes of TAM schedule overruns. Hence, this research aims to make recommendations for reducing rework events by enhancing the knowledge reuse process. This research focuses on the TAM projects in Pupuk Kaltim, a petrochemical company in Indonesia. This research draws the data from 9 interviews and examines the company’s relevant documents. The data was then used to develop a fault tree to derive the causes of rework. Among five others, rework events are caused by knowledge issues, namely worker inattention to work instructions and employee knowledge gaps. Subsequently, the activity theory was used to describe the current practice of the knowledge reuse process. It is found that knowledge reuse occurs through both person-to-person and person-to-document ways. As boundary spanners, people may arrive in different communities in different TAM projects. Thus, knowledge reuse occurs through the employee’s network. On the other hand, the documents work as the boundary object. As a tool involved in every stage of the TAM project setting, it must be well developed and maintained. Nevertheless, this is not the case. Activity theory models are also helpful to discover the enabler and the barriers of the knowledge reuse process. Those enablers are (1) people found abnormality, (2) leadership and working environment, (3) familiarity among each other, (4) a need for specifics and details, (5) assistance from an expert/knowledge producer, and (6) work’s passive by-product to record the knowledge. On the other hand, the barriers to reusing the knowledge are (1) low explicit knowledge quality, (2) it is not correctly indexed, (3) the expert lacks props, (4) lack of incentives, (5) resources, and (6) standards for reporting and evaluation meetings to reintegrate knowledge. Based on these factors, it is proposed to use new web-based tools to capture the knowledge from the execution stage and update work instructions. Moreover, it is also suggested to develop guidelines to formally capture the knowledge at the closing stage and reuse it at the planning stage, which encompasses knowledge about equipment and failures, especially previous rework events. This solution is polished through expert validation, where it must also be reinforced by strong leadership and organizational support. Through this research, it is expected to broaden empirical findings on learning in project and maintenance management. Finally, this research is also likely to enhance the knowledge reuse process in turnaround project contexts for companies who similarly conduct their turnaround projects as Pupuk Kaltim.