NIPPLE-DIAG 2681528 - Caterpillar

Removal Procedure
Do not allow dirt to enter the fuel system. Thoroughly clean the area around a fuel system component that will be disconnected. Fit a suitable cover over disconnected fuel system component.
Keep all parts clean from contaminants.Contaminants may cause rapid wear and shortened component life.
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Refer to Special Publication, NENG2500, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat products.Dispose of all fluids according to local regulations and mandates.
Illustration 1 g01371903
Typical example
Disconnect the fuel lines (1) and (2). Inspect the condition of the rubber olives (not shown) that seal the fuel lines. If the olives are damaged or worn, use new parts for replacement. Note: Put identification marks on all the fuel lines for installation purposes. Plug all the fuel lines and all the ports in the fuel filter base. This helps prevent fluid loss, and this helps to keep contaminants from entering the system.
Remove the fuel filter element (4). Refer to Operations and Maintenance Manual, "Fuel System Secondary Filter - Replace".
If necessary, remove the plugs (5), the washers (6) and the inner seals (7).
Remove the setscrews (8) and the nuts (not shown).
Remove the fuel filter base (3) from the engine.