Due to the high heat carrier density, using microcapsule phase change material (MPCM) slurry as engine coolant instead of water was presented. To match the engine cooling temperature, a novel microcapsule was prepared based on phase change paraffin with phase transition temperature range of 78-85 degrees C as core and urea-formaldehyde as resin shell. To improve thermal conductivity of the microcapsule, a composite microcapsule phase change material (CMPCM) was also prepared by inlaying graphene into urea formaldehyde resin shell. By dispersing microcapsule in water, microcapsule slurries were prepared. To analyze the feasibility in engine cooling system, an experimental study on the flow resistance characteristics of microcapsule slurries in a circular tube was conducted. The pressure drops of slurries for turbulent flow were measured and the effects of such facts as the concentration and flow velocity were discussed. According to the pressure characteristic and latent heat of the slurry, the pumping consumption rates of slurries to water under a given heat transportation quantity can be obtained. The results show that mass flow rate and pumping consumption of slurries decrease greatly compared with water, which indicate that the microcapsule slurries are promising media for engine cooling system. (C) 2016 Elsevier Ltd. All rights reserved.