Complex sentence: During the transfer, the two tanks suffered from various mechanical break downs; the cooling system was insufficient for the excessively hot climatic conditions, where the engine tended to overheat and cause a consequential failure of the gearbox.
Split into simpler sentences: During the transfer, the two tanks suffered from various mechanical break downs. The cooling system was insufficient for the excessively hot climatic conditions, where the engine tended to overheat and caused a consequential failure to the gearbox.