A downhole combustor system for a production well is provided. The downhole combustor includes a housing, a combustor and an exhaust port. The housing is configured and arranged to be positioned down a production well. The housing further forms a combustion chamber. The combustor is received within the housing. The combustor is further configured and arranged to combust fuel in the combustion chamber. The exhaust port is positioned to deliver exhaust fumes from the combustion chamber into a flow of oil out of the production well.