TUBE AS 3043354 - Caterpillar

Fuel leaked or spilled onto hot surfaces or electrical components can cause a fire. To help prevent possible injury, turn the start switch off when changing fuel filters or water separator elements. Clean up fuel spills immediately.
Ensure that the engine is stopped before any servicing or repair is performed.
After the engine has stopped, you must wait for 60 seconds in order to allow the fuel pressure to be purged from the high pressure fuel lines before any service or repair is performed on the engine fuel lines. If necessary, perform minor adjustments. Repair any leaks from the low pressure fuel system and from the cooling, lubrication or air systems. Replace any high pressure fuel line that has leaked. Refer to Disassembly and Assembly Manual, "Fuel Injection Lines - Install".
The water separator can be under suction during normal engine operation. Ensure that the drain valve is tightened securely to help prevent air from entering the fuel system.
Place a suitable container under the water separator in order to catch any fuel that might spill. Clean up any spilled fuel.
Illustration 1 g01476633
Typical example
Install a suitable tube onto the drain (1). Open the drain (1). Allow the fluid to drain into the container.
Tighten the drain (1) by hand pressure only. Remove the tube and dispose of the drained fluid in a safe place. Primary Filter with a Vent Screw
Illustration 2 g01371846
Typical example
Note: Not all primary filters require vent screw (2). This primary fuel filter that has a vent screw may be installed on a fuel system that has a low fuel tank.
Install a suitable tube onto drain (1). Loosen vent screw (2).
Open drain (1). Allow the fluid to drain into the container.
Tighten drain (1) by hand pressure only. Remove the tube and dispose of the drained fluid in a safe place.
Tighten vent screw to 6 N m (53 lb in).