SPRING 0969154 - Caterpillar

Probable Causes
Fan blades and/or spider may be damaged
Air-to-air-after-cooler (ATAAC) intake air flow restriction
Cooler cores are not operating efficiently
Fan control solenoid may be bad or lost connection with the ECM
Any of the temperature sensors involved in the fan control strategy are not providing accurate data
Pump control valve is not operating properly
Fan pump is not operating properlyRecommended Actions
Note: Care must be taken in order to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the machine. You must be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component that contains fluid. Dispose of all fluids according to local regulations.Fan Blades And/Or Spider May Be Damaged
Damage to the fan blades can negatively affect the efficiency of the fan, reducing the volume of air the blades move. Erosion of the leading edges or the tips of the fan blade can also reduce the efficiency of the fan.If blade wear, or erosion occurs, the engine ECM will try to compensate for the inefficiencies by speeding up the fan. At the extreme, the fan cannot rotate fast enough to make up the difference. This condition may cause overheating and make the fan sound like the fan is running faster than necessary. Inspect each of the eight fan blades for damage, especially the leading edges. If the edges are bent or damaged, or if the blade is bent or flattened out, replace the fan assembly.Inspect the spider for damage. If the spider is bent or twisted, replace the fan assembly.Air - To - Air - After - Cooler (Ataac) Intake Air Flow Restriction
Normal intake manifold air pressure with high intake air and/or exhaust temperature can be caused by blockage of the fins of the ATAAC core. Ensure that the fins of the ATAAC core are clean and are not restricted. Check and clean any buildup of debris from the exterior of the ATAAC core, the fan, and/or the fan shroud. Clean and repair as necessary.Clean the cooling fins of the ATAAC periodically. Clean the cooling fins more frequently if the operating environment includes contamination and debris that can easily clog the fins (such as wood chips, landfill debris, coal dust). Externally flush the ATAAC core with water, in order to remove dirt and foreign objects. If possible, flush the fins from the front side, which is the opposite direction of normal air flow through the fins. Blow dry the assembly in the