Vapor phase lubrication has been investigated as a method of lubricating the piston ring/liner interface of low heat rejection engines. Tests were run in a single cylinder engine which contained several ceramic components. One test was run with vapor phase lubrication using tricresyl phosphate and the second test was run with no intentional lubrication. The wear coefficients for the vapor phase lubrication piston ring and liner were reduced by 52% and 72%, respectively, compared to those obtained with no intentional lubrication. The wear coefficients produced using vapor phase lubrication were two orders of magnitude greater than those produced in conventional diesel engines.