PISTON-LARGE 7N6817 - Caterpillar

Removal Procedure
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 g00694495
Section view of the secondary fuel filter
Personal injury can result from parts and/or covers under spring pressure.Spring force will be released when covers are removed.Be prepared to hold spring loaded covers as the bolts are loosened.
Connect one end of a hose to each drain valve (1). Insert the other end of the hoses into a suitable container in order to catch the fuel. Note: If filters are installed vertically, put the drain valves in the bottom.
Remove both vent plugs (2) and the O-ring seals. Open both drain valves (1) in order to drain the fuel filters.
Gradually loosen but do not remove the last two bolts that are on the opposite sides of cover (3). Before removing the last two bolts, pry the cover loose or tap the cover with a rubber mallet in order to relieve any spring pressure. Remove covers (3) and O-ring seals (4) from both fuel filter housings. Discard the O-ring seals.
Elements (6) are installed on wire rack (5). Remove wire racks (5). Discard the used elements. Installation Procedure
Keep all parts clean from contaminants.Contaminants may cause rapid wear and shortened component life.
Illustration 2 g00694495
Section view of the secondary fuel filter
Improper assembly of parts that are spring loaded can cause bodily injury.To prevent possible injury, follow the established assembly procedure and wear protective equipment.
Clean covers (3), wire racks (5), and the inside of the fuel filter housings. Install new O-ring seals (4).
Inspect new elements (6) for good condition. Install the elements on wire racks (5).
Install covers (3). Ensure that the spring is seated properly between the covers and the retainer for the elements.
Close drain valves (1). Clean vent plugs (2). Install the vent plugs and the O-ring seals loosely. Prime the fuel system. Purge the air from the filter housing. Refer to Operation and Maintenance Manual, "Fuel System - Prime".