OTTO Excavator Parts Zx330 6Hk1 Thermostat Tube 1137105660 113710-5660 1-13710566-0 For Isuzu The OTTO Excavator Parts Zx330 6Hk1 Thermostat Tube, with part number 1137105660, is designed for Isuzu engines. It ensures proper cooling system functionality by regulating the flow of coolant through the engine, helping to maintain optimal operating.