SHAFT-PLANETARY 3T7431 - Caterpillar

Reduced hours of operation at full load will result in a lower average power demand. A decreased average power demand should increase both the engine service life and the overhaul interval.The need for an overhaul is generally indicated by increased fuel consumption and by reduced power.The following factors are important when a decision is being made on the proper time for an engine overhaul:
The need for preventive maintenance
The quality of the fuel that is being used
The operating conditions
The results of the S O S analysisOil Consumption as an Overhaul Indicator
Oil consumption, fuel consumption, and maintenance information can be used to estimate the total operating cost for your Caterpillar engine. Oil consumption can also be used to estimate the required capacity of a makeup oil tank that is suitable for the maintenance intervals.Oil consumption is in proportion to the percentage of the rated engine load. As the percentage of the engine load is increased, the amount of oil that is consumed per hour also increases.The oil consumption rate (brake specific oil consumption) is measured in grams per kW/h (lb per bhp). The brake specific oil consumption (BSOC) depends on the engine load. Consult your Caterpillar dealer for assistance in determining the typical oil consumption rate for your engine.When an engine's oil consumption has risen to three times the original oil consumption rate due to normal wear, an engine overhaul should be scheduled. There may be a corresponding increase in blowby and a slight increase in fuel consumption.Overhaul Options
Using Fuel Consumption For Calculating the Overhaul Intervals
Experience has shown that maintenance intervals are most accurately based on fuel consumption. Fuel consumption corresponds more accurately to the engine load. Table 1 lists average ranges of fuel consumption for a load factor of approximately 60 percent.
Table 1
Service Hours and Fuel Consumption for C32 Generator set (1)    
Top End Overhaul     7500 Service Hours    
946360 L (250000 US gal)
Major Overhaul     15000 Service Hours    
1892700 L (500000 US gal)
( 1 ) Fuel consumption is based on a load factor of approximately 60 percent.
Table 2
Equation For Calculating Overhaul Intervals    
F/R = H    
"F" is the estimated total amount of fuel consumption of the engine.    
"R" is the rate of fuel consumption in liters per hour or gallons per hour.    
"H" is the number of estimated hours until the overhaul interval.    Use the actual records of fuel consumption, when possible. If the actual records are not available, use the following procedure in order to estimate the fuel consumption.
Estimate the average percent of the load for the operation of the engine.