0432143 JOHNSON PLUNGER & VALVE ASSY.

Top End Overhaul
The following definitions explain the terminology for the services that are performed during an overhaul:Inspect - Inspect the 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". The guidelines were developed to help Cat dealers and customers to avoid unnecessary expenditures. New parts are not required if the existing parts can still be used, reconditioned, or repaired. If the components are not in the reusability guidelines, refer to the Service Manual, "Specifications" module.Rebuild - The component is reconditioned to comply with reusability guidelines.Replace - The service life of the part is exhausted. The part may fail before the next maintenance interval. The part must be replaced with a part that meets functional specifications. The replacement part may be a new part, a CAT remanufactured part, a rebuilt part, or a used part. Some worn components may be exchanged with your Cat dealer for a credit on replacement parts. Consult your Cat dealer about repair options for your engine.If you elect to perform an overhaul without the services of a Cat dealer, be aware of the recommendations in Table 2.Note: Overhaul intervals can vary dependent on several factors such as engine load, time of operation, and engine ratings.
Table 1
Overhaul Intervals
Interval Fuel Consumption
Rating Tier A B C
(>20% Time >85% Load) C**
(<20% Time >85% Load)
Top End 1000000 L 1000000 L 1000000 L 500000 L
Major 2000000 L Cylinder Head Assembly
Inspect the cylinder head assembly 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".Your Cat dealer can provide these services and components. Your Cat dealer can ensure that the components are operating within the appropriate specifications.The use of out-of-spec parts will cause unscheduled downtime and/or costly repairs.Unit Injectors
Replace the unit injectors. Consult your Cat dealer about exchanging the unit injectors. Your Cat dealer can provide these services and components.The wear of unit injectors is affected by the following considerations:
Quality of the fuel
Quality of the filtration of the fuelThe wear of the unit injectors can result in elevated levels of exhaust emissions and/or poor engine performance. The misfire of a single cylinder is not typically attributed to normal wear. This condition can be repaired by replacing the faulty unit injector.The following lists of circumstances indicate that the unit injectors should be inspected more frequently:
Use of fuels that are not recommended in this Operation and Maintenance Manual, "Fluid Recommendations"
Extreme ambient temperatures that reduce the ability of the fuel to provide lubrication
Frequent plugging of the fuel filters
Insufficient maintenance of the fuel tank or the fuel storage tank that can allow excessive water, sediment, and other foreign matter.
Insufficient maintenance of the fuel filtersOil Suction Screen
Clean the oil suction screen after the oil has been drained.Note: Approximately 1 L (1 qt) of oil will remain in the oil housing after the sump has been drained. This oil will pour out of the oil housing when the cover is removed. Prepare to catch the oil in a pan. Clean up any spilled oil with absorbent towels or pillows. DO NOT use absorbent particles to clean up the oil.
Remove the cover.
Remove the screen assembly according to the instructions in the Service Manual, "Disassembly and Assembly" module. Discard the used O-ring seals.
Inspect the screen assembly. Obtain a new screen assembly, if necessary.
Wash the screen assembly in clean nonflammable solvent. Allow the screen assembly to dry before installation.
Install the screen assembly and install new O-ring seals according to the instructions in the Service Manual, "Disassembly and Assembly" module.
Install the cover.
Remove side covers to gain access to the sump. Clean the bottom of the sump with absorbent towels or pillows. When the bottom of the sump is clean, install the side covers.Inspect, Rebuild, and Replacement of Components
Table 2
Recommendations for Top End Overhauls (1)
Service Top End Overhaul
Inspect
Rebuild Cylinder head assemblies
Rebuild Diesel Exhaust Fluid Pump(2)
Replace Valves
Inspect Aftercooler core(3)
Inspect Heat exchanger(4)
Inspect
Replace Rocker arms
Inspect
Replace Valve bridges
Clean/Test Oil cooler core(5)
Replace Cylinder head gaskets
Replace Fuel Injectors
(1) For instructions on removal and installation of components, see the Service Manual, "Disassembly and Assembly" module.
(2) Refer to this Disassembly and Assembly Manual, M0075247–01, "Control Cabinet - Assemble" for the procedure.
(3) Refer to this Operation and Maintenance Manual, M0078454, "Aftercooler Core - Inspect" for the procedure.
(4) Refer to this Operation and Maintenance Manual, M0078454, "Heat Exchanger - Inspect" for the procedure.
(5) Refer to this Operation and Maintenance Manual, M0078454, "Oil Cooler Core - Check/Clean/Test" for the procedure.Inspection 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".
Aftercooler core
Aftertreatment - air regulator
Aftertreatment - CEM housing and mounting structure
Aftertreatment - DEF nozzle
Camshaft
Driven equipment (alignment)
Engine control module
Exhaust bellows shields
Oil suction screen