380093 Thermostat, used on the Hercules D4800 and D5000 series engine.380093 Thermostat, for the Hercules D4800 5000 series engines. Please see the Hercules drawing for a good visual, this will be item number 6 in the Hercules drawing. There will be a slight difference in design, the replacement thermostat uses a rubber seal at the flange and a slightly smaller control spring. The valve assembly is the same as the earlier style.