RELAY AS 4437387 - 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.
Illustration 1 g02178189
(1) Fuel supply connections
(2) Fuel filter
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 any disconnected fuel system components.
Use a suitable container to catch any fuel that might spill. Clean up any spilled fuel immediately.
It may be necessary to relieve residual fuel pressure from the fuel system before removing the fuel filter. Loosen one of the fuel supply connections (1) in order to purge any residual pressure.
Do not loosen fuel lines or fittings at the fuel manifold or ECM. The engine components may be damaged.
Remove the used fuel filter.
Clean the gasket sealing surface of the fuel filter base. Ensure that all of the old gasket is removed.
Apply clean diesel fuel to the new fuel filter gasket.
Do not fill the secondary fuel filter with fuel before installing. The fuel would not be filtered and could be contaminated. Contaminated fuel will cause accelerated wear to fuel system parts.
Install the new fuel filter. Spin the fuel filter onto the fuel filter base until the gasket contacts the base. Use the rotation index marks on the filters as a guide for proper tightening. Tighten the filter for an additional 3/4 turn by hand. Do not overtighten the filter.