PUMP & MTG GP-BRAKE & HYD FAN 3155944 - Caterpillar

Probable Causes
Diagnostic codes
Misreading of fuel level
Fuel quality
Quality of oil
Low engine temperature
Prolonged operation at idle speed
Engine operating speed
Air intake and exhaust system
Reduced pressure of intake air
Excessive valve lash
Failure of the primary speed/timing sensorRecommended Actions
Diagnostic Codes
Use the electronic service tool to check for any diagnostic codes that may be related to high fuel consumption. Misreading of Fuel Level
Monitor the fuel consumption over a period of 50 engine hours. If the fuel consumption is excessive, perform the following procedure. Fuel Quality
The quality of the fuel that is used in the engine will affect the rate of fuel consumption. Refer to "General Fuel Information" in the Operation and Maintenance Manual, "Refill Capacities".
If the fuel is not of an acceptable quality, drain the fuel system and replace the fuel filters. Refill the fuel system with fuel of an acceptable quality. Refer to the applicable sections in the Operation and Maintenance Manual.
If the fuel is of an acceptable quality, refer to "Quality of Oil". Quality of Oil
The nominal viscosity of the lubricating oil that is used in the engine will affect the rate of fuel consumption. The viscosity of lubricating oil is defined by the SAE grade of the lubricating oil. The grade of the lubricating oil must be correct for the ambient conditions. Lubricating oil that is intended for use in high ambient temperatures will have a negative effect upon the rate of fuel consumption in cold ambient temperatures. Refer to "Engine Oil" in the Operation and Maintenance Manual, "Refill Capacities".
The actual viscosity of the lubricating oil that is used in the engine will change throughout the service life of the oil. Lubricating oil that is heavily contaminated will have a negative effect upon the rate of fuel consumption.
If the oil is not of an acceptable quality or if the oil has exceeded the service life, drain the oil system and replace the oil filters. Refill the oil system with oil of an acceptable quality. Refer to the applicable sections in the Operation and Maintenance Manual.
If the oil is of an acceptable quality, refer to "Low Engine Temperature". Low Engine Temperature
The operating temperature of the engine will affect the rate of fuel consumption. Operation of the engine below the correct temperature will increase fuel consumption. Failure of the water temperature regulator can prevent the engine from operating at the correct temperature.
If the engine operating temperature is low, check the operation of the water temperature regulator. If the water temperature regulator does not operate correctly, a new water temperature regulator must be installed. Refer to Disassembly and Assembly, "Water Temperature Regulator - Remove and Install". Prolonged Operation at Idle Speed
Prolonged operation of the engine at idle speed increases fuel consumption. When the engine is operated at idle speed, the fuel that is consumed provides no useful work. Prolonged operation at idle speed will cause a measurable deterioration in the overall fuel consumption of the engine.Operation of the engine for long periods at idle speed will cause a deterioration of the internal components of the