CONTROLLER AS 3997793 - Caterpillar

Illustration 1 g00728915
176-7712 Fuel Transfer Pump (1) Fuel Transfer Pump (2) O-ring SealNote: Ensure that 176-7719 O-Ring Seal (2) is installed on the pump.
Illustration 2 g00729035
129-6259 Fuel Priming Pump Kit (3) Cap Ring (4) Center Cap (5) Cover/Plunger Assembly (6) O-ring Seal (discard) (7) Diaphragm (rubber) (8) Volume Plug (white) (9) Spring Cap (10) Spring (11) Valve Plate (12) Filter Header
Unscrew cap ring (3) that is located on filter header (12) and remove center cap (4). If the hand primer is removed, center cap (4) must be reinstalled. O-ring seal (6) must be discarded and a new O-ring seal must be used if the center cap is reinstalled.
If the fuel filter base is equipped with a white volume plug (8) that is located directly behind center cap (4), remove the plug and save the plug. The plug may need to be used again if the hand primer is ever removed from the fuel filter base. If there is a mesh screen in the fuel filter base, leave the screen in position. The mesh screen will not interfere with the installation of the hand primer.
Apply a thin film of oil on the O-ring seal and on valve plate (11) .
Insert valve plate (11) into the fuel filter base. The valve plate must be installed with the O-ring first. Ensure that the extended rubber valve is piloted through the center hole of the header. Push valve plate (11) firmly into the correct position.
Install spring (10) into valve plate (11) and place spring cap (9) on top of the spring.
Install rubber diaphragm (7) into cover/plunger assembly (5). Ensure that diaphragm (7) fits firmly into the correct position. Place the assembly over spring cap (9) .
Install cap ring (3) over cover/plunger assembly (5). Depress cover/plunger assembly (5) until diaphragm (7) is seated firmly onto filter header (12). Tighten cap ring (3) hand tight while the cover/plunger assembly is depressed.