Diesel engines are heat-generating sources. They are cooled by circulating a water-based coolant through a water jacket, which is part of the engine.
JD195P 14HP at 68000
JD1105P 18HP at 74,000
JD1115P 24HP at 93,000
JD1130P 30HP at 102,000
JD1135P 35HP at 120,000