Refer to this Operation and Maintenance Manual, "Maintenance Recommendations" to determine the maintenance interval for an in-frame overhaul.
Typically, an in-frame overhaul does not require the engine to be removed. Instead, the service is performed with the engine in place. If the customer requires a minimum disruption in the production of power, the engine can be replaced with a rebuilt model of identical specifications.
Note: The generator or the driven equipment may also require service when the in-frame overhaul is performed.
An in-frame overhaul includes all the work that is done for a top end overhaul. Also, some other components that wear are replaced. Some components are inspected for good condition. Some components are reconditioned or replaced, if necessary.
Your Cat dealer can provide these services and components. Your Cat dealer can ensure that the components are operating within the appropriate specifications.
If you elect to perform an in-frame overhaul without the services of a Cat dealer, be aware of the following recommendations.
For instructions on removal and installation of components, see the Service Manual, "Disassembly and Assembly" module.
Replace the following worn components with new components during the in-frame overhaul.
- Aftercooler core
- Aftertreatment catalysts
- Aftertreatment sensors (Temperature, Level, Pressure)
- Connecting rod bearings
- Crankshaft seals
- Crankshaft thrust washer
- Crankshaft vibration damper bolts
- Exhaust manifold bellows, clamps, bolts
- Exhaust manifold seals
- Common rail fuel injectors
- Flex pipe bellows and clamps
- Flex pipe bellows heat shields
- Flywheel bolts
- Fuel injectors
- Fuel transfer pump
- High-pressure fuel pump
- Hydraulic Lash Adjusters(HLA) pushrods
- Inlet manifold gaskets and seals
- Main bearings
- Piston rings
- Turbocharger
Inspection, Reconditioning, or Exchanging of Components
Inspect the following components according to the instructions that are in Cat reusability publications. Refer to Guidelines for Reusable Parts and Salvage Operations, SEBF8029, "Index of Publications on Reusability or Salvage of Used Parts".
Recondition the worn components or exchange the components, if necessary. Your Cat dealer can provide these services and components.
- Camshaft followers
- Coolant temperature regulator (Jacket Water)
- Crankshaft vibration damper
- Cylinder head assembly
- Fuel pressure regulating valve
- Jacket water pump
- Oil cooler bypass valve
- Oil cooler core
- Oil pressure regulating valve
- Pre-lube pump
- Rocker shaft
- Rocker arms
- Starting motors
- SCAC water pump
Inspect the following components according to the instructions that are in Cat reusability publications. Refer to Guidelines for Reusable Parts and Salvage Operations, SEBF8029, "Index of Publications on Reusability or Salvage of Used Parts".
- Aftertreatment air regulator
- Aftertreatment air stainer
- Aftertreatment DEF nozzle
- Aftertreatment DEF strainer
- Aftertreatment solenoid valve
- Camshaft
- Camshaft bearings
- Crankshaft
- Driven equipment (alignment)
- Engine control module
- Engine heat shielding
- Engine wiring harness
- Exhaust bellows shields
- Exhaust manifold
- Turbine outlet elbows
- Flywheel
- Flywheel ring gear
- Flexible heat shielding
- Front gear train
- Gear train bushings and bearings
- Gear train front
- Gear train rear
- High-pressure fuel lines
- Inlet manifold
- Oil pump
- Software
Inspect the camshaft for damage to the journals and the lobes. Inspect the following components for signs of wear and/or for signs of fatigue:
- Camshaft bearings
- Camshaft followers
Inspect the crankshaft for any of the following conditions:
- Deflection
- Damage to the journals
- Bearing material that has seized to the journals
Check the journal taper and the profile of the crankshaft journals. Check these components by interpreting the wear patterns on the following components:
- Rod bearing
- Main bearings
Note: If the crankshaft or the camshaft are removed for any reason, use the magnetic particle inspection process to check for cracks.
Replace the crankshaft vibration damper if any of the following conditions occur:
- Engine failure due to a broken crankshaft
- Excessive wear of the front bearing for the crankshaft
- Excessive wear of the gear train that is not caused by a lack of lubrication
Inspect the gears of the gear train and inspect the gear train bushings for the following conditions:
- Worn gear teeth
- Unusual fit
- Unusual wear
In addition to the inspection of components, inspect the alignment of the driven equipment. See the Application and Installation Guide for the engine or see the literature that is provided by the OEM of the driven equipment.
Clean the oil cooler core and the aftercooler core. Then, pressure test both of these cores. For instructions on cleaning the cores, see this Operation and Maintenance Manual, "Aftercooler Core - Inspect/Clean" topic.
Clean the oil suction screen. Also, remove side covers to clean the oil sump. For instructions on removal and installation of components, see the Service Manual, "Disassembly and Assembly" module.
For a conventional heavy-duty antifreeze/coolant solution, check the concentration of supplemental coolant additive (SCA) regularly. The concentration of SCA can be checked with an S·O·S coolant analysis (Level 1). A more detailed coolant analysis is recommended periodically.
For example, considerable deposits are found in the water jacket areas on the external cooling system, but the concentrations of coolant additives were carefully maintained. The water in the coolant probably contained minerals which were deposited on the engine over time.
A coolant analysis can be conducted to verify the condition of the water that is being used in the cooling system. A full water analysis may be obtained from the following sources:
- Cat dealer
- Local water utility company
- Agricultural agent
- Independent laboratory
Cat recommends an S·O·S coolant analysis (Level II) which is a comprehensive chemical evaluation of the coolant. This analysis is also a check of the overall condition inside the cooling system. The following services are provided:
- Full Level 1 analysis
- Identification of the source of metal corrosion and of contaminants
- Identification of buildup of the impurities that cause corrosion
- Identification of buildup of the impurities that cause scaling
- Determination of possible electrolysis within the engine cooling system
A report of the results of the analysis is provided. Maintenance recommendations are based on the results.
For more information about S·O·S coolant analysis, consult your Cat dealer.