TRUNNION AS 5J7263 - Caterpillar

Probable Causes
Engine Oil Cooler
Leak in the engine oil coolerPower Train Oil Cooler (if equipped)
Leak in the power train oil coolerCylinder Head Gasket
Cylinder head gasket
Cylinder headBlock
Cylinder liner
Cylinder blockRecommended Actions
Note: The procedures have been listed in order of probability. Complete the following procedures in the order that is provided.Verify the presence of oil in the coolant with a scheduled oil sample. Verification must be made before following the procedure.Leak in the Engine Oil Cooler
Check for leaks in the engine oil cooler. Refer to Testing and Adjusting for the proper procedure. If a leak is found, install a new oil cooler core. Refer to the Disassembly and Assembly manual.
Flush the cooling system. Refer to the Operation and Maintenance Manual for the proper flushing procedure. Refill the cooling system with the proper coolant. Refer to the Operation and Maintenance Manual for the correct coolant and capacities.
Check the oil for coolant. If coolant is found in the oil, drain the crankcase. Refill the crankcase with the proper oil after the leak has been repaired. Refer to the Operation and Maintenance Manual for the correct oil capacities and viscosity. Leak in the Power Train Oil Cooler
Check for leaks in the power train oil cooler. Refer to Testing and Adjusting for the proper procedure. If a leak is found, install a new oil cooler. Refer to the Disassembly and Assembly manual.
Flush the cooling system. Refer to the Operation and Maintenance Manual for the proper flushing procedure. Refill the cooling system with the proper coolant. Refer to the Operation and Maintenance Manual for the correct coolant and capacities.
Check the oil for coolant. If coolant is found in the oil, drain the oil. Refill the oil after the leak has been repaired. Refer to the Operation and Maintenance Manual for the correct oil capacities and viscosity. Cylinder Head Gasket
Remove the cylinder head. Refer to the Disassembly and Assembly manual.
Check the cylinder liner projection. Refer to the Systems Operation/Testing and Adjusting manual.
Install a new cylinder head gasket and new water seals in the spacer plate. Refer to the Disassembly and Assembly manual. Cylinder Head
Check for cracks in the cylinder head. Perform a leak test on the cylinder head. Refer to Systems Operation/Testing and Adjusting for the proper procedure for checking the cylinder head. If a crack is found, repair the cylinder head and/or replace the cylinder head. Refer to the Disassembly and Assembly manual.Cylinder Liner
Check for cracked cylinder liners. Replace any cracked cylinder liners. Refer to the Disassembly and Assembly manual. Check the liner projections. Refer to Systems Operation/Testing and Adjusting for the proper liner projections.Cylinder Block
Inspect the cylinder block for cracks. If a crack is found, repair the cylinder block or replace the cylinder block. Inspect the deck of the engine. Refer to the Reuse and Salvage Guidelines for the proper inspection