SPACER 1394084 - Caterpillar

Overhaul Intervals
Some factors that are important for determining the overhaul intervals include the following considerations:
Performance of preventive maintenance
Use of recommended lubricants
Use of recommended coolants
Use of recommended fuels
Proper installation
Operating conditions
Operation within acceptable limits
Engine load
Engine speedGenerally, engines that are operated at a reduced load and/or speed achieve more service life before an overhaul. However, this is for engines that are properly operated and maintained.Other factors must also be considered for determining a major overhaul:
The total amount of fuel consumption
The service hours of the engine
An increase of oil consumption
An increase of crankcase blowby
The wear metal analysis of the lube oil
An increase in the levels of noise and vibrationAn increase of wear metals in the lube oil indicates that the bearings and the surfaces that wear may need to be serviced. An increase in the levels of noise and vibration indicates that rotating parts require service.Note: It is possible for oil analysis to indicate a decrease of wear metals in the lube oil. The cylinder liners may be worn so that polishing of the bore occurs. Also, the increased use of lube oil will dilute the wear metals.Monitor the engine as the engine accumulates service hours. Consult your Caterpillar dealer about scheduling a major overhaul.Note: The driven equipment may also require service when the engine is overhauled. Refer to the literature that is provided by the OEM of the driven equipment.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. Tables 1 and 2 list average ranges of fuel consumption and service hours for high displacement engines. These tables are based on a load factor of approximately 60 percent.High Displacement Engines
Table 1
Service Hours and Fuel Consumption for 3512B High Displacement Engines (1)    
Interval     Rated Up to 1300 RPM     Rated 1301 to 1600 RPM     Rated 1601 to 1800 RPM    
Top End Overhaul     11000 Service Hours     9000 Service Hours     7500 Service Hours    
1500000 L (395000 US gal) of fuel
Major Overhaul     22000 Service Hours     18000 Service Hours     15000 Service Hours    
3000000 L (790000 US gal) of fuel
( 1 ) Fuel consumption is based on a load factor of approximately 60 percent.
Table 2
Service Hours and Fuel Consumption for 3516B High Displacement Engines (1)    
Interval     Rated Up to 1300 RPM     Rated 1301 to 1600 RPM     Rated 1601 to 1800 RPM    
Top End Overhaul     11000 Service Hours     9000 Service Hours     7500 Service Hours    
2000000 L (528000 US gal) of fuel
Major Overhaul     22000 Service Hours     18000 Service Hours     15000 Service Hours    
4000000 L (1056000 US gal) of fuel
( 1 ) Fuel consumption is based on a load factor of approximately 60 percent.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