Life cycle assessment of heavy equipment engine remanufacturing in Indonesia

Indonesia's mining sector relies heavily on diesel engines that often suffer failure, thus replacing them is expensive and carbon intensive. Remanufacturing offers a cost-effective, lower-emission alternative, but its environmental profile remains underexplored. This study conducts a gate-to-gate LCA of remanufacturing 12-V diesel engines. Results show the remanufacturing stage itself accounts for roughly 80% of total life-cycle impact, primarily marine ecotoxicity driven by upstream electricity consumption and the complex operations needed to restore worn cores to original condition. Disassembly proves the most burdensome sub-step, generating 642.22 kg CO2-eq. (32% of total impact) through compressed-air tools and lubricants. Component-level analysis reveals that large, intricate parts such as block, crankshaft and cylinder head dominate burdens; the block alone contributes 570 kg CO2-eq. due to its mass and machining intensity. The study recommends targeted energy-efficiency improvements and strategic component prioritisation. Comparative assessments against new manufacture or alternative recovery strategies (refurbishment, reconditioning) are proposed for future work.