Cooling Systems

Types of Replacement Cooling System Parts

Thermostats regulate warm-up and running temperature. Stuck open, the engine never reaches operating temperature, which shows up as poor cab heat and a diesel that runs cool and wet rather than one that overheats. Stuck closed, it overheats within minutes. Both failures come from the same inexpensive part, which is why a thermostat is worth replacing on suspicion rather than on proof.

Fans, pulleys, and drive components move air through the cooler stack. A cracked fan blade or a pulley bearing starting to seize will often be heard before it is seen. Reserve tanks and pressure caps hold the system's expansion volume and set its boiling point, and a cap that no longer holds pressure lowers that boiling point on its own.

Before ordering any of it, look at the cooler faces. On compact machines the oil cooler and radiator sit stacked together in a tight space that packs with chaff, dust, and seed. A plugged core is a far more common cause of a hot machine than a failed thermostat or fan, and it is cleared by blowing out from the fan side so the debris exits the way it came in.