828175A 1 Mercury GEAR ASSEMBLY, Reverse - 15/28

Service Hours and Fuel Consumption
Experience has shown that maintenance intervals are most accurately based on fuel consumption. Fuel consumption corresponds more accurately to the engine load.Use the actual records of fuel consumption, when possible. If the actual records are not available, use the following procedure to estimate the fuel consumption.Use gallons, hours, or load cycles, WHICHEVER OCCURS FIRST, to determine Overhaul.Operating at greater than 800 m (2625 ft) altitude and 40° C (104° F) ambient conditions for an extended time, may decrease overhaul intervals. Contact your Cat dealer for assistance.
Table 1
Overhaul Schedule
Fuel Consumption 4542492 L (1200000 US gal) 4542492 L (1200000 US gal) 4542492 L (1200000 US gal) 4542492 L (1200000 US gal)
Load Factor < 25 Per Cent 25 - 30 Per Cent 30 - 50 Per Cent > 40 Per Cent
Service Hours 24000 21000 18500 16000
Load Cycles(1)(2) 192000 192000 192000 192000
(1) To illustrate engine capability, a load cycle has been defined as an increase of at least an 80 per cent rated power followed by a decrease of at least 80 per cent rated power. Load cycles of less than 80 per cent rated power may also impact the engine overhaul interval, requiring your specific operating profile to determine your appropriate interval.
(2) Determining the appropriate overhaul interval will require understanding of the locomotive operating profile including total operating hours, amount of fuel burned, load factor, load cycles, and total number of engine starts. Caterpillar requires the use of data recorders to help determine the operating profile and to set appropriate intervals for a fleet on a given route. Changes in operating profiles (a different deployment or change in the operating profile for the existing route) may require adjustment of overhaul intervals to ensure reliable performance. Failure to follow the overhaul intervals may result in unplanned repairs. For assistance with calculating load cycles, installing data recording equipment and/or confirming overhaul intervals, contact your Cat dealer.
Estimate the average percent of the load for the operation of the engine.
Refer to the fuel consumption data in the Technical Marketing Information (TMI) for your engine. Use this figure as variable "F" for the equation in Table 2. For more information about the Technical Marketing Information (TMI) for your engine, consult your Cat dealer.
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. Engine Starts as an Overhaul Indicator
Engines that experience a high number of engine starts may be susceptible to accelerated component wear. This wear may include, but not limited to, the main bearings and camshaft lobes.For applications that exceed 6500 engine starts before the fuel burn, operating hours, or load cycles to overhaul limits are met, consult your Cat dealer for guidance. Your Cat dealer will identify a course of action including an appropriate inspection and repair plan.Oil Consumption as an Overhaul Indicator
Oil consumption, fuel consumption, and maintenance information can be used to estimate the total operating cost for your Cat 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 Cat dealer for assistance in determining the typical oil consumption rate for your engine.When an engine 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.Severe Operation
Severe operation is the use of an engine that exceeds current published standards for that engine. Caterpillar maintains standards for the following engine parameters:
Altitude
Environmental qualities
Fuel consumption
Fuel quality
Horsepower
Installation
Maintenance intervals
Range of rpm
Selection of coolant
Selection of oilRefer to the standards for your engine or consult your Cat dealer to determine if your engine is operating within the defined parameters.Severe operation can accelerate component wear. Engines that are operating under severe conditions may need more frequent maintenance intervals for the following reasons:
Maximum reliability
Retention of full service lifeBecause of individual applications, identifying all the factors which can contribute to severe operation may not be possible. Consult your Cat dealer about the maintenance that is needed for your specific engine.The following factors can contribute to severe operation: environment, improper operating procedures, and improper maintenance practices.Environmental Factors
Extreme Ambient Temperatures
Extended operation in environments that are cold or hot can damage components. Valve components can be damaged by carbon buildup if the engine is frequently started and stopped in cold temperatures. Hot inlet air reduces the performance capabilities of the engine.Note: See this Operation and Maintenance Manual, "Cold-Weather Operation" topic (Operation Section), or see Special Publication, SEBU5898, "Cold-Weather Recommendations".