Category Archives: Cummins 4BT

Preparatory Steps: • Remove the drive belt. • Remove the fan pulley. 10 mm Remove the four capscrews and replace the fan hub. Torque Value: 24 N®m [18 ft-lb]  

Preparatory Step: • Remove the drive belt. 13 mm Remove the four capscrews, fan and spacer. Replace the fan pulley. Torque Value: 24 N®m [18 ft-lb]  

Preparatory Step: • Remove the drive belt 15 mm Remove the capscrew and replace the tensioner. Torque Value: 43 N«m [32 ft-lb]  

Lift the tensioner to remove and install the drive belt. NOTE: The belt tensioner is spring loaded and must be pivoted away from the drive belt. Pivoting in the wrong direction can result in damage to the belt tensioner.  

Gauges and sensors are used in the system to measure the coolant temperature. These can malfunction and pro­vide an incorrect temperature indication. Caution: Overfueling can cause the engine to overheat. Make sure that the fuel pump is calibrated correctly. Caution: Constant overloading (lugging) can cause the engine to run hot.  

The thermostat controls the coolant temperature. When the coolant temperature is below the operating range, coolant is bypassed back to the inlet of the water pump. When the coolant temperature reaches the operating range, the thermostat opens, sealing off the bypass, forc­ing coolant to flow to the radiator. Caution: Never operate the engine without a… Read More »

Air forced through the fins of the radiator by a fan cools the coolant pumped through the radiator. Environmental debris (paper, straw, lint, dust, etc.) can obstruct the fins and stop the flow of airwhich will reduce the cooling effect of the radiator. If the fan is belt driven, aslipping belt will result in a… Read More »

The water pump pulls coolant from the bottom of the radiator and pumps it through the engine back to the top of the radiator for cooling. Reduced or interrupted flow will result in the engine running hot. The pump is belt driven from the crankshaft pulley. An automatic belt tensioner is used to prevent the… Read More »

The system is designed to use a pressure cap to prevent boiling of the coolant. Different caps are specified for the two recommended systems: An incorrect or malfunctioning cap can result in the loss of coolant and the engine running hot. Air in the coolant can result in loss of coolant from the overflow when… Read More »

The function of the coolant system is to maintain a spec­ified operating temperature for the engine. Some of the heat generated by the engine is absorbed by the coolant flowing through the passages in the cylinder block and head. Then, heat is removed from the coolant as it flows through the radiator. When you troubleshoot… Read More »