A method and apparatus for maintaining equipment, such as an engine, in readiness for use while it is otherwise nonoperational. The equipment or engine is of the type having a closed liquid recirculation system. The present method and apparatus bypasses the usual recirculating pump in this system. An...http://www.google.de/patents/US4245593?utm_source=gb-gplus-sharePatent US4245593 - Liquid heating and circulating system
