Fuel Selector Valve Ford Econoline E150

DESCRIPTION

Two fuel selector valves are used. Gasoline engine models use a mechanically-activated dual function reservoir, while diesel equipped vehicles use a 6-port fuel selector valve.

The dual function reservoir combines reservoir/filter function with tank selector valve function. The dual function reservoir system uses 3 fuel pumps: 2 low pressure pumps in tank and one external high pressure pump. The 6-port fuel selector valve does not contain a filter or reservoir and a single mechanical fuel pump.

Scheme 278

Scheme 279

Dual Function Reservoir (Gasoline Engine)

The fuel tank selector valve on gasoline-engine vehicles is located in fuel filter/reservoir, mounted on left frame rail. The valve is not actuated electrically. The valve is operated by fuel pressure from the low-pressure in-tank fuel pumps.

When tank selector switch is in "FRONT" or "REAR" position, power from fuel pump relay is directed to front or rear tank fuel pump, respectively. Pressurized fuel from fuel pump moves a diaphragm in dual function reservoir, connected to sliding supply and return shutoff valves. The shutoff valves allow fuel to be drawn and returned to proper tank. (Scheme 278)and (Scheme 279).

The tank selector valve allows fuel to flow from one tank, depending on switch position. The fuel selector switch directly energizes tank selector valve. A relay is not used.

Scheme 280

Scheme 281

TESTING

Fuel Does Not Switch Tanks (Diesel Engine)

1. Remove electrical connector from tank selector valve. Turn ignition switch to "RUN" position. Move selector switch to "FRONT" position. Check for voltage between connector terminals No. 2 and 1. If voltage did not exist, proceed to step 3). If voltage exists, check voltage between terminal No. 2 and ground. If voltage exists, proceed to next step. If not, proceed to step 3).
2. Place a jumper wire on battery positive terminal and selector valve terminal No. 2. Connect jumper wire to selector valve terminal No. 1 and to ground. Selector valve motor should operate. Reverse jumper wires. Motor should operate in opposite direction. Replace motor if valve does not operate in both directions. If motor is okay, proceed to step 4).
3. Check for voltage across fuse No. 15 (10-amp) in fuse panel. Repair faulty circuit or replace fuse if no voltage exists. If voltage exists, proceed to next step.
4. Remove fuel tank selector switch from dash. Remove harness connector. Position selector switch in proper position and check for continuity at specified terminals. See «SWITCH TEST TERMINALS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-selector-valve) . Replace switch if continuity does not exist at designated terminals. SWITCH TEST TERMINALS Switch Position Test Terminals FRONT Step 1 Nos. 1 & 2 Step 2 Nos. 4 & 5 REAR Step 1 Nos. 2 & 3 Step 2 Nos. 5 & 6
5. If continuity exists, check continuity of circuits No. 786 (Red) and 789 (Brown/White) between selector switch and selector valve. If continuity exists, proceed to next step. If no continuity exists, repair open circuit.
6. Turn ignition switch to "RUN" position. Position selector switch to "FRONT" position. Turn ignition off. Disconnect fuel supply line from rear tank to selector valve.
7. Remove vacuum purge valve from fuel filter adapter. Install Adapter (3019) and sample hose from Rotunda Pressure Test Kit. Place sample hose in measuring container. Start engine and allow to idle with no load. Open clamp on sample hose and note fuel flow.
8. Fuel flow should be solid and continuous. If fuel flow is okay, remove adapter, reconnect hose and proceed to step 10). If fuel flow is restricted, proceed to next step.
9. Disconnect engine supply hose at selector valve. Disconnect front tank supply hose from selector valve. Connect hoses together. Repeat steps 6) through 8). Replace tank selector valve if fuel flow was continuous. If fuel flow was restricted, check fuel tank sender, fuel level and fuel lines for restrictions. Repeat steps 6) through 8).
10. Turn ignition switch to "RUN" position. Position selector switch to "REAR" position. Turn ignition off. Disconnect fuel supply line from front tank to selector valve.
11. On all models, remove vacuum purge valve from fuel filter adapter. Install Adapter (3019) and sample hose from Rotunda Pressure Test Kit. Place sample hose in measuring container. Start engine and allow to idle with no load. Open clamp on sample hose and note fuel flow.
12. Fuel flow should be solid and continuous. If fuel flow is okay, remove adapter, reconnect hose and proceed to step 14). If fuel flow is restricted, proceed to next step.
13. Disconnect engine supply hose at tank selector valve. Disconnect rear tank supply hose from tank selector valve. Connect hoses together. Repeat steps 10) through 12). Replace tank selector valve if fuel flow was continuous. If fuel flow was restricted, check fuel tank sender, fuel level and fuel lines for restrictions. Repeat steps 10) through 12).
14. Disconnect engine return hose at tank selector valve. Place hose in a container. Turn ignition switch to "RUN" position. Position selector switch to the problem tank. Start engine and check fuel flow. If fuel flow was okay, proceed to next step. If fuel flow was restricted, check fuel lines for obstructions.
15. Disconnect fuel return line to problem tank at selector valve. Attach a 5/16" diameter hose to selector valve return port. Place hose in container. Start engine and check fuel flow. Replace tank selector valve if fuel flow was restricted. If fuel flow was okay, check fuel sender and fuel lines for obstructions.

DUAL FUNCTION RESERVOIR

1. Remove and mark lines from reservoir. Apply regulated air pressure of 3-5 psi (.2-.3 kg/cm 2 ) to the small diameter tube (return port) on the engine side of reservoir. Engine side contains 2 ports. (Scheme 278)and (Scheme 279).
2. If air exhausts from only one port on other side of reservoir, proceed to step 4). If air did not exhaust, block supply port (large tube) on engine side of reservoir.
3. Apply regulated air pressure to either of the supply ports on the fuel tank side of reservoir. Remove regulated air and apply to return tube on engine side of reservoir. If air exhausts from one tank side return port, proceed to next step. Replace reservoir if air did not exhaust from one tank side return port.
4. Block engine side supply port. Apply regulated air pressure to one corresponding supply and return port on tank side. Air pressure should exhaust on engine side return port.
5. If air pressure did not exhaust, apply air pressure to opposite tank side return port. Replace reservoir if air pressure did not exhaust on engine side return port.
6. If air pressure exhausted from engine side return port, repeat step 4) on remaining corresponding tank side ports. Check connection or replace reservoir if air pressure did not exhaust on engine side return port.
7. If air exhausted from engine side return port during steps 4) and 6), return blockage from engine side supply port.
8. Apply pressure to engine side supply line. Note the open port on tank side. Install a 0-10 psi (0-.70 kg/cm 2 ) pressure gauge on the closed supply port.
9. Block the open tank side port. Apply air pressure. Replace reservoir if air pressure exists on the gauge. If no pressure exists, remove pressure gauge. Install gauge on closed tank side return port.
10. Apply air pressure on engine side return port. Block open return port. Replace reservoir if air pressure exists on gauge.

Disconnect and mark fuel hoses from selector valve. Remove electrical connections. Remove nut and ground wire (if equipped). Remove valve retaining bolts. Remove valve. To install, reverse removal procedure. Ensure ground wire is securely fastened.

Disconnect and mark fuel lines at reservoir. Remove reservoir retaining bolts. Remove reservoir. Reverse removal procedures for installation. Tighten retaining bolts to 12-17 ft. lbs. (16-23 N.m).

FUEL LINE FITTINGS

Scheme 282

1. Clean fuel supply fitting prior to separation. Some fittings may stick between seals and tubing. Twist fitting on tube, then push and pull fitting until it moves freely. Fuel lines may be of 2 different types. One uses a hairpin clip connector and one uses a metal spring lock connector.
2. On hairpin clip type, bend tab downward until it clears fitting body. (Scheme 282) Spread 2 clip legs 1/8" each to disengage body and push legs into fitting. Pull clip from fitting and discard clip. Pulling in an axial direction, separate tube from fitting. Reverse procedure for installation. Use new hairpin clip.
3. On metal spring lock type, use Spring Lock Coupling Disconnect Tool (T81P-19623-G2) to separate coupling fitting. Align mating marks on connector to ensure positive proper mating at installation.

WIRING DIAGRAMS

For wiring diagrams, see WIRING DIAGRAMS section.

See also:
• SWITCH TEST TERMINALS