NUT-HEX FLANGE 1757141 - Caterpillar

Remove the core. Refer to the Service Manual for the procedure.
Turn the aftercooler core upside-down in order to remove debris.
Do not use a high concentration of caustic cleaner to clean the core. A high concentration of caustic cleaner can attack the internal metals of the core and cause leakage. Only use the recommended concentration of cleaner.
Back flush the core with cleaner. Caterpillar recommends the use of Hydrosolv liquid cleaner. Table 1 lists Hydrosolv liquid cleaners that are available from your Caterpillar dealer.
Table 1
Hydrosolv Liquid Cleaners(1)
Part Number Description Size
1U-5490 Hydrosolv 4165 19 L (5 US gallon)
174-6854 Hydrosolv 100 19 L (5 US gallon)
(1) Use a two to five percent concentration of the cleaner at temperatures up to 93°C (200°F). Refer to Application Guide, NEHS0526 or consult your Caterpillar dealer for more information.
Steam clean the core in order to remove any residue. Flush the fins of the aftercooler core. Remove any other trapped debris.
Wash the core with hot, soapy water. Rinse the core thoroughly with clean water.
Personal injury can result from air pressure.Personal injury can result without following proper procedure. When using pressure air, wear a protective face shield and protective clothing.Maximum air pressure at the nozzle must be less than 205 kPa (30 psi) for cleaning purposes.
Dry the core with compressed air. Direct the air in the reverse direction of the normal flow.
Inspect the core in order to ensure cleanliness. Pressure test the core. Many shops that service radiators are equipped to perform pressure tests. If necessary, repair the core.
Install the core. Refer to the Service Manual for the procedure. For more information on cleaning the core, consult your Caterpillar dealer.