DESCRIPTION
The fuel pump is a wet type where the vane rollers are directly coupled to a motor filled with fuel. A relief valve in the pump is designed to open when pressure in fuel system rises above a safe limit. A check valve on fuel pump outlet prevents an abrupt drop in pressure in fuel lines when engine is stopped.
OPERATION
Fuel pump is actuated by a fuel pump relay when ignition switch is in "START" or "ON" positions. As fuel goes through pump, it is routed to a fuel damper mounted near fuel pump. The damper reduces pulsations in fuel lines. The fuel pump and damper are mounted in front of the fuel tank (or in fuel tank on some models). Starion relief valve will open at 64-85 psi (4.5-6.0 kg/cm 2 ).
Scheme 29
OPERATION TEST
- Connect jumper wire across terminals of fuel pump check connector located in engine compartment. Turn ignition on. Listen for sound of fuel pump operating.
- If no sound is heard, check electrical circuit. If circuit is good, replace fuel pump.
PRESSURE TEST
Note. No test procedure available for Mitsubishi models.
Removal & Installation
- Relieve fuel system pressure. Disconnect negative battery cable. Raise and support vehicle. On externally-mounted pumps, clamp hose between fuel tank and pump. Disconnect fuel hoses from fuel pump.
- Unplug harness connector from fuel pump. Remove fuel pump bracket-to-body bolts. Remove fuel pump and fuel damper as an assembly. Separate damper from fuel pump.
- On internally-mounted pumps, disconnect all fuel and electrical connections at fuel tank. Lower and remove fuel tank. Remove pump from fuel tank.
- To install both types of pumps, reverse removal procedure.