In a message dated 10/18/2007 8:07:09 A.M. Pacific Daylight Time, flywheelin at hotmail.com writes: I have put up some pictures of the little Hercules Power Plant. Luke, Is this engine thermo siphon cooled - no water pump? Francis Maciel Santa Maria, Ca 93454 ************************************** See what's new at http://www.aol.com