Fuel Injection System - Diesel Ford Econoline E150

DESCRIPTION

The diesel fuel injection pump is an opposed plunger, inlet metered, positive displacement, distributor pump. The pump incorporates a single pumping chamber, an integral fuel transfer pump and governor, and an automatic injection advance mechanism. On-off control is provided by an electric solenoid located in the injection pump housing cover.

Fuel from the tank is routed to fuel supply pump which pumps fuel through a combination fuel filter, heater, and water separator. Fuel enters the inlet of the injection pump and is delivered under high pressure through the injectors into the cylinders for combustion. Each injector is equipped with a fuel return fitting and excess fuel from the injectors and injection pump are collected in bleed-off lines and returned to fuel tank.

A vacuum switch located in fuel filter head will activate a light on instrument panel when filter needs replacement. A probe in the water separator portion of fuel filter assembly will activate a warning light on instrument panel when filter/water separator requires draining at the water and sediment drain, located at bottom of assembly.

Scheme 10

FUEL INJECTION PUMP

The fuel injection pump is an opposed plunger, inlet metered, positive displacement, distributor type pump. Fuel under transfer pump pressure flows through the center of transfer pump rotor, past the rotor retainers into the hydraulic head. It then flows through a connecting passage in the head to the automatic advance and up through a radial passage to the metering valve. The position of the metering valve, controlled by the governor, regulates fuel flow into the radial charging passage which incorporates the head charging ports. As the rotor revolves, the 2 rotor inlet passages align with the charging ports in the hydraulic head, allowing fuel to flow into the pumping chamber.

With further rotation, the inlet passages move out of alignment and the rotor discharge port aligns with one of the head outlets. While the discharge port is opened, the rollers contact the cam lobes, forcing the plungers together. Fuel trapped between the plungers is then pressurized and delivered by the injector to the combustion chamber.

INJECTORS

The injectors spray fuel into a pre-chamber as each compression stroke occurs. The injector receives a high pressure pulse of fuel, which forces open the injector needle valve, allowing fuel to pass into pre-chamber.

FUEL SUPPLY SYSTEM

Fuel from tank is routed to the fuel supply pump, which pumps fuel through a combination fuel filter, heater and water separator. A fuel shutoff solenoid controls flow of fuel into the injection pump charging circuit (high pressure). With ignition in the "START" or "RUN" positions, the solenoid is energized and fuel is allowed to flow to the injection pump charging circuit. With ignition switch in the "OFF" position, fuel flow to the injection pump charging circuit stops.

FUEL INJECTION LINES

High pressure fuel injection lines are routed from injection pump to an injector in each cylinder. The lines are of equal length but are bent differently to prevent any difference in timing from cylinder to cylinder and aid in installation. Lines are not interchangeable and are pre-bent by manufacturer.

Scheme 11

The solid state glow plug system consists of the glow plug controller (mounted on rear of intake manifold), glow plug harness assembly, and glow plugs. The system determines glow plug temperature by electronically measuring the resistance of glow plugs. It then maintains this temperature regardless of ambient temperature.

The afterglow operation of the glow plugs continues after the "WAIT TO START" light turns off. The glow plugs cycle on and off for a period of time. This helps reduce white smoke after engine start-up. The system can be recycled by turning ignition off and on. The engine can be started as soon as the "WAIT TO START" light goes off.

Cold Engine

1. Check and follow correct starting procedure listed on vehicle visor (if available). If vehicle starts, return vehicle to owner and explain starting procedure. If vehicle does not start, go to next step. NOTE: If ignition is left on and engine is not started within 2 minutes, the glow plug system must be reset by turning ignition off.
2. Listen for click from glow plug controller relay when ignition is turned on. If click is heard, go to next step. If no click is heard, go to «GLOW PLUG SYSTEM & DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/ignition-system/#glow-plug-system-diagnosis) .
3. Loosen one injector line nut 1/2 to one turn while cranking engine. If fuel discharges, go to «GLOW PLUG SYSTEM & DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/ignition-system/#glow-plug-system-diagnosis) . If no fuel discharges, go to next step.
4. Check shutoff solenoid terminal (located at front of injection pump) for dirt, loose connection or damage. Check voltage at shutoff terminal while cranking engine, voltage at terminal should be at least 9 volts. If voltage is correct, go to next step. If not, clean, repair or replace terminal. After service, repeat this step.
5. Check voltage at cold advance solenoid terminal (located on left rear of injection pump). While cranking engine, voltage at terminal must be at least 9 volts. If voltage is correct, go to «ENGINE PERFORMANCE DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & TESTING. If not, verify switching function of temperature sensing switch, located behind thermostat housing. After service, repeat this step.

Engine At Normal Operating Temperature

1. Check and follow correct starting procedure listed on vehicle visor (if available). If vehicle starts, return vehicle to owner and explain starting procedure. If vehicle does not start, go to next step. NOTE: If ignition is left on and engine is not started within 2 minutes, the glow plug system must be reset by turning ignition off.
2. Loosen one injector line nut 1/2 to 1 turn. Crank engine. If fuel discharges, go to «ENGINE PERFORMANCE DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & TESTING. If no fuel discharges, go to next step.
3. Check shutoff solenoid terminal (located at front of injection pump) for dirt, loose connection or damage. Turn ignition on, check shutoff solenoid voltage. Voltage at terminal must be at least 9 volts. If voltage is correct, go to «ENGINE PERFORMANCE DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & TESTING. If not, clean, repair, or replace terminal. After service, repeat this step.

ENGINE QUITS, STALLS OR STUMBLES

1. Check engine idle speed by performing step 17 of ENGINE PERFORMANCE DIAGNOSIS under DIAGNOSIS & TESTING. If idle speed is correct, go to next step. If not, adjust idle speed. See «HOT (SLOW) IDLE RPM»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under ADJUSTMENTS.
2. Check shutoff solenoid terminal (located at front of injection pump) for dirt, loose connection or damage. While cranking engine, voltage at terminal must be at least 9 volts. If voltage is correct, go to step 3 or 4 as required. If not, clean, repair, or replace terminal connection. After service, repeat this step.
3. On COLD engine, check voltage at cold advance solenoid terminal (located at left rear of injection pump) while cranking engine. Voltage must be at least 9 volts. If voltage is correct, go to «ENGINE PERFORMANCE DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & TESTING. If not, verify switching function of temperature sensing switch, located behind thermostat housing. After service, repeat this step.
4. On HOT engine, check voltage at cold advance solenoid terminal (located at left rear of injection pump) while cranking engine. No voltage should be present. If no voltage is present, go to «ENGINE PERFORMANCE DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & TESTING. If voltage is present, replace temperature sensing switch. After service, repeat this step.

ENGINE MISSES

1. Determine when engine miss occurs. Engine will miss when cold if one or more glow plugs are not heating. If engine misses only when cold, go to «GLOW PLUG SYSTEM & DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/ignition-system/#glow-plug-system-diagnosis) . If engine misses at normal operating temperature, go to next step.
2. Loosen each injector line nut (one at a time) while engine is running. If miss is isolated to specific cylinder(s), go to next step. If miss is not isolated, go to «ENGINE PERFORMANCE DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & TESTING.
3. Check injector fuel line(s) for kinks or restrictions and test injectors. See «INJECTORS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & TESTING. If lines and injectors are okay, go to next step. If not, replace defective line(s) and/or clean or replace injector(s).
4. Perform cylinder compression test. If engine compression is within specifications (compression is considered normal if lowest reading cylinder is 75 percent of the highest reading cylinder), go to «ENGINE PERFORMANCE DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & TESTING. If not, go to next step.
5. Check crankcase pressure by performing step 20 of «ENGINE PERFORMANCE DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & TESTING. If okay, service or replace engine valve train. If not, repair proper cylinder.

ENGINE KNOCKS

1. Check engine front drive components for proper operation. If okay, go to next step. If not, service or replace as necessary.
2. Verify that engine is not overheating. If not overheating, go to next step. If engine is overheating, service cooling system.
3. Isolate engine knock. Loosen each injector line nut (one at a time) while engine is running. If engine knock is isolated to specific cylinder(s), go to next step. If engine knock is not isolated, go to «ENGINE PERFORMANCE DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & TESTING.
4. Check injector fuel line(s) for kinks or restrictions and test injectors. See «INJECTORS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & TESTING. If the line(s) and injector(s) are okay, go to «ENGINE PERFORMANCE DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & REPAIR. If not, replace line(s) and/or clean or replace injector(s).

LOW OIL PRESSURE W/ PROPER OIL LEVEL

1. Verify accuracy of oil pressure transducer. Use Adapter (5633) with Pressure Test Kit (014-00761). If pressure is okay, go to next step. If not, replace oil pressure transducer.
2. Change engine oil and oil filter. Run engine until normal operating temperature is reached. Check oil pressure reading. If oil pressure is not okay, service or replace lubrication components as necessary.

EXCESSIVE BLUE/WHITE SMOKE

1. Verify that engine coolant temperature stabilizes in normal operating range. If engine coolant temperature stabilizes, go to step 3. If it does not, go to next step.
2. Remove thermostat, check heat range, and test for proper operation. If thermostat is okay, replace thermostat housing with integral air bleed check valve. Repeat step 1. If not okay, replace thermostat and repeat step 1.
3. Check engine oil level for excessive oil fill. If level is correct, go to next step. If not, drain excess oil. If problem persists, go to next step.
4. Perform fuel return pressure test as described in step 12 of «ENGINE PERFORMANCE DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & REPAIR. If fuel return pressure is correct, perform entire engine diagnostic procedure. If not, service or replace fuel return line(s) as necessary. After repairs, repeat this step.

EXCESSIVE BLACK SMOKE

1. Verify under what conditions Black smoke occurs. This condition is considered normal when going up steep grades, pulling trailer, under maximum acceleration, or at high altitudes. If under light load and/or low altitude, go to next step.
2. Check exhaust system condition by performing step 2 of «ENGINE PERFORMANCE DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & REPAIR. Record problem and results. If exhaust is okay, go to next step. If not okay, service or replace exhaust system as necessary. If problem persists, go to next step.
3. Check air cleaner for restrictions by performing step 13 of «ENGINE PERFORMANCE DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & REPAIR. Record problem and results. If okay, go to next step. If not, replace air filter element and/or service system. After service, repeat this step.
4. Check injection pump dynamic timing by performing step 18 of «ENGINE PERFORMANCE DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) . If timing is correct, go to next step. If not, adjust timing. See «INJECTION PUMP DYNAMIC TIMING»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under ADJUSTMENTS. If the problem persists, go to next step.
5. Check fuel line(s) and injector(s) by performing step 19 of «ENGINE PERFORMANCE DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & TESTING. If okay, replace injection pump. If not okay, replace damaged fuel line(s) and/or clean or replace injector(s). If problem persists, replace injection pump.

1. Always use CLEAN calibration fluid in Injector Test Stand (Rotunda 014-00300). Install injector on tester. Open test stand valve slightly and operate tester handle 8-10 quick strokes to bleed air from injector. Fluid should discharge from injector.
2. Check injector opening pressure. Close pump valve, and operate pump handle in slow even strokes to bring system up to pressure. Record highest pressure reached before injector opens. Repeat operation, increasing handle speed is necessary to establish consistent reading.
3. Opening pressure for a NEW injector should be 1800-1950 psi (126-137 kg/cm 2 ). If injector opening pressure is below 1425 psi (100 kg/cm 2 ) on a used injector, replace injector.
4. Using test stand, maintain pressure at about 200 psi (14 kg/cm 2 ) below opening pressure obtained in step 2. No fuel leakage should occur. Slight wetting of tip is acceptable as long as drop does not fall within 5 seconds. If leakage occurs, injector(s) must be replaced.
5. After testing is complete, open the pump valve to release pressure prior to removing injector from tester. When injector is removed, cap nozzle tip and inlet until installed back in engine.

Test Preparation

The engine performance diagnostic procedure tests those items which are high frequency, easy to diagnose problems, and progresses to the low frequency, hard to diagnose problems. Proper use of this procedure will provide a rapid as well as accurate diagnosis. Connect Pressure Test Kit (Rotunda 014-00702) to components shown. (Scheme 12)

Scheme 12

Diagnostic Procedure

1. With engine running, check for coolant, fuel, oil, and air intake system leaks. If no leaks are detected, go to next step. If leaks are detected, service or replace faulty component(s). If problem persists, go to next step.
2. Check exhaust system for dents or kinks which may cause restrictions. If okay, go to next step. If not okay, repair or replace exhaust system components. After repairs, go to next step.
3. Check for air in fuel. Install a piece of clear hose, in place of rubber hose, between fuel filter outlet and fuel return system. Start and run engine at idle for 2 minutes. Increase engine speed to 3000 RPM and check for bubbles in hose. Go to next step. NOTE: Correct direction of fuel flow is from fuel filter toward fuel return system. Fuel flow in opposite direction indicates restriction in fuel supply system. On dual tank vehicles, check fuel flow with tank selector in both positions for a minimum of 2 minutes.
4. If fuel flow is correct and bubbles are less than 1/16" (1.6 mm) in diameter, go to next step. If fuel flow is correct, but bubbles are large in diameter, perform «FUEL SYSTEM AIR LEAK DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & TESTING in this article and repeat step 3. If fuel flow is incorrect, go to step 12. Repeat step 3, when fuel flow direction is correct.
5. Obtain a fuel sample and visually examine fuel (in a clear container) for dirt/rust particles, clouding, or water contamination. If okay, go to next step. If not okay, replace fuel filter. Clean and/or service fuel system as required. After repairs, go to next step.
6. Using cetane tester included with Dynamic Timing Meter (Rotunda 078-00200), check cetane value of fuel sample. Cetane value must be more than 40. If okay, go to next step. If not okay, perform steps 7, 12, 13, and 16. Also tell owner to use higher rated fuel. DO NOT replace injection pump because of low cetane value.
7. Remove air bleed orifice hose from fuel filter fitting. Install Adapter (5651) and pressure test kit. (Scheme 13) Start and run engine at 3300 RPM, without accessory load. Record pressure reading. On dual tank vehicles, check both tanks. Pressure should be minimum of one psi (.07 kg/cm 2 ) at 3300 RPM. If okay, go to step 9. If not, go to next step.
8. Remove vacuum purge valve from fuel filter adapter. Install Adapter (3019) and Pressure Test Kit (014-00761). (Scheme 13) Ensure clamp is closed on fuel sample hose. Leave adapter from step 7 installed and cap end. Start and run engine at idle, without load. Record pressure reading. On dual tank vehicles, check both tanks. If pressure is at least 2 psi (.14 kg/cm 2 ), replace fuel filter and repeat step 7. If not, go to next step.
9. Position end of sample hose on Adapter (3019) in a clear, quart graduated container. Follow instructions in step 8 and open sample hose for 30 seconds, allowing fuel to flow into container. Record volume. On dual tank vehicles, check both tanks.
10. Volume should be at least one pint (.47L) in 30 seconds at idle. If both pressure and volume are okay, go to step 12. If pressure is okay, but volume is not, go to next step. If volume is okay, but pressure is not, replace fuel supply pump and repeat step 7. If both pressure and volume are incorrect, go to next step.
11. Connect fuel return line removed in step 7. Install Adapter (5632) and pressure test kit to fuel supply pump inlet. With rear wheels off ground, start and run engine (without load) at 3300 RPM. Place transmission in Park (A/T) or Neutral (M/T). Record vacuum reading. On dual tank vehicles, check both tanks. Vacuum should be less than 6 in. Hg. If okay, go to step 7. If not okay, service or replace restricted fuel return line(s) and repeat step 7.
12. Connect fuel return line removed in step 7. Remove fuel return line fitting (located on left rear of engine). Install Adapter (5663) and pressure test kit. Start and run engine (without load) at 3300 RPM with transmission in Park or Neutral. Record pressure reading. On dual tank vehicles, check both tanks. Pressure should not exceed 2 psi (.14 kg/cm 2 ) at 3300 RPM. If okay, go to next step. If not okay, service or replace restricted fuel return line(s) and repeat this step.
13. Remove cap on air cleaner test port and install Adapter (5650) and pressure test kit. (Scheme 13) Start and run engine at 3300 RPM, without accessory load. Record restriction reading. Reading should not exceed 25 in. of water.
14. If reading is more than 2 in. of water, but less than 25 in. of water, remove adapter. Install cap on air cleaner port and go to next step. If reading is more than 25 in. of water, replace filter element and check air intake system for blockage. After service, repeat this step. If reading is less than 2 in. of water, correct restriction on air cleaner test port and repeat this step.
15. Remove screw from transfer pump pressure port cover. Install Adapter (T83T-9000-A) and "O" ring through cover and into port. Install Adapter (5850) and pressure test kit. Start and run engine (without load) at 3300 RPM with transmission in Neutral. Record pressure reading. If pressure is 90-110 psi (6.3-7.7 kg/cm 2 ), go to next step. If not, replace injection pump. If problem persists, check and adjust dynamic timing. If problem continues, go to next step.
16. With engine off, check that throttle lever contacts injection pump stop when accelerator pedal is fully depressed. If okay, go to next step. If not okay, adjust accelerator linkage. After adjustment, go to next step. NOTE: Do not adjust position of full throttle stop screw. Tampering may cause injection pump damage.
17. Start engine and bring to normal operating temperature. Check engine idle speed. See «HOT (SLOW) IDLE RPM»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under ADJUSTMENTS. If idle speed is correct, go to next step. If not, adjust idle speed as necessary and then go to next step.
18. Start engine and bring to normal operating temperature. Check injection pump dynamic timing. See «INJECTION PUMP DYNAMIC TIMING»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under ADJUSTMENTS. Compare value to specification and correct for cetane value and altitude. If timing is correct, go to next step. If not, adjust timing. If problem persists, go to next step.
19. Check injector inlet lines for kinks or restrictions and test injectors. See «INJECTORS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & TESTING. If lines and injectors are okay, go to next step. If not okay, replace damaged line(s) and clean or replace injector(s). If problem persists, go to next step.
20. Remove Crankcase Depression Regulator (CDR) valve (located on intake manifold behind air inlet) and plug opening to prevent blow-by. Remove oil fill cap and install Adapter (5631) and pressure test kit. (Scheme 13) Ensure dipstick is seated in dipstick tube. Start and run engine (without load) at 3300 RPM with transmission in Neutral. Record pressure reading. Pressure should not exceed 6 in. of water. If reading is correct, replace injection pump. If not, internal engine problem exist.

Before starting diagnostic procedure, verify that fuel tank(s) contain at least half a tank of fuel. Visually inspect fuel lines for obvious problems such as kinked hoses, damaged lines or push-to-connect fittings.

Hard starting, excessive White smoke, poor idle quality, or lack of power under load may be caused by several conditions. One of these conditions is air leaks in the fuel supply system. To perform fuel system air leak diagnosis, the following adapters need to be fabricated. (Scheme 13)

Scheme 13

1. Verify that push-to-connect fitting clip is in place. Verify that fittings are properly installed on tube end by pulling fitting (axially) away from tube.
2. If fitting does pull away, push fitting back on tube until a definite click is heard. Pull and push fitting one more time to verify proper installation. If okay, go to next step. If not okay, service or replace fuel lines, clips, or push-to-connect fittings.
3. Remove rubber fuel return by-pass hose which connects fuel filter outlet fitting by-pass orifice to return lines at injectors. Install a clear hose (to view fuel flow) in place of rubber hose. Lubricate hose with fuel to ease installation. Tighten hose clamps. Start and run engine at 3000 RPM for 2-3 minutes to clear air from system.
4. Observe hose for air bubbles with engine at 3000 RPM. A continuous stream of air bubbles larger than 1/16" (1.6 mm) indicates air in system. A concentration of bubbles of any size, or foam, is unacceptable. If no bubbles are detected, problem is elsewhere in system. Install rubber by-pass hose. If bubbles are detected, go to next step.
5. Observe direction of flow of bubbles. Bubbles should flow from fuel filter outlet fitting to fuel return system. If okay, go to next step for SINGLE tank system, step 8 for DUAL tank system. If not okay, fuel system is restricted. Go to step 7 of «ENGINE PERFORMANCE DIAGNOSIS»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel) under DIAGNOSIS & TESTING.
6. Check for damage to hose connections at rubber fuel hose from chassis fuel line to mechanical lift pump and at inlet and outlet hoses at water separator. Tighten clamps if necessary.
7. After tightening clamps, start and run engine at 3000 RPM for 5 minutes. Check for air bubbles in clear hose. If no bubbles are detected, problem has been corrected. Install rubber by-pass hose. If bubbles are detected, go to next step.
8. Disconnect water separator inlet hose. Install hose adapter and tighten clamps. Disconnect water separator outlet hose. Install hose adapter and tighten clamps. Start and run engine at 1500 RPM for 5 minutes. Increase engine speed to 3000 RPM for an additional 2 minutes and check for bubbles in hose adapters.
9. On SINGLE tank system, if bubbles are present in inlet hose, service hoses and connections between water separator. After repair, repeat step 8. On DUAL tank system, if bubbles are present in inlet hose, go to step 11.
10. On both systems, if bubbles are present in outlet hose only, check hose adapter at water separator inlet for air leaks. Stop engine and drain water separator. See «FUEL/WATER SEPARATOR»(/ford/econoline-e150/1987-1991/remont/testing-diagnostics/#fuel-injection-system-diesel__fuelwater-separator) under MAINTENANCE. After draining separator, repeat step 8. If bubbles persist, replace water separator and repeat step 3.
11. Start and run engine at 3000 RPM. Observe clear hose while switching selector valve between tanks. If bubbles are detected in both tank positions, repeat step 6. If bubbles are detected in only one position, check push-to-connect fittings as stated in step 1. If okay, go to next step. If not okay, service or replace fittings.
12. Disconnect push-to-connect fittings from fuel tank selector valve for affected tank. Install push-to-connect adapters between fuel lines and selector valve. Start and run engine at 3000 RPM for 2-3 minutes. Run engine an additional 2 minutes and check for bubbles in hose adapters.
13. If no bubbles are detected in either adapter, air leak is between fuel tank selector valve and water separator. Service fuel lines and connections as necessary. After service, repeat step 3.
14. If bubbles are detected in both adapters, the air leak is between fuel tank and the selector valve. Service fuel lines and connections as necessary. After service, repeat step 3. If bubbles are detected in selector valve outlet adapter only, replace the selector valve and repeat step 3.

Removal

1. Disconnect battery negative cables from both batteries. On vans, remove engine cover. On all models, remove adapter housing cover plate.
2. Disconnect electrical connectors from injection pump. Disconnect accelerator cable and cruise control cable (if equipped) from throttle lever. Remove air cleaner and cover air intake.
3. Remove fast idle solenoid bracket assembly to provide access to injection pump mounting nuts. Disconnect accelerator cable and cruise control cable from throttle lever. Remove air cleaner and install Intake Manifold Cover (T83T-9424-A).
4. Remove accelerator cable bracket (with cables attached) from intake manifold and position out of the way. On vans, remove fuel inlet and return lines from fuel filter. Remove filter bracket and filter as an assembly. Cap all openings.
5. On all models, remove fuel line from injection pump inlet and cap fittings. Remove injection pump inlet elbow and fitting adapter. Cap inlet elbow and fitting.
6. Remove fuel return line from injection pump, rotate out of way and cap all fittings. If injector lines are to be removed, loosen line fittings at pump before removing it from engine. Disconnect fuel lines from injectors and cap line fittings and injectors.
7. Using Injection Pump Mounting Wrench (T86T-9000-C), remove 3 injection pump retaining nuts. On "F" Series, remove injection pump with injector lines attached. DO NOT carry injection pump by fuel injector lines.
8. On vans, if injection pump is to be replaced, remove injector lines from pump and cap all fittings. Injector lines must be removed in the following order: 5-6-4-8-3-1-7-2. (Scheme 14) Remove injection pump from engine passenger compartment.

Scheme 14

1. To install, reverse removal procedure. Use a new "O" ring on drive gear end of injection pump. Install injector lines AFTER pump is installed. Lines must be installed in the following order: 2-7-1-3-8-4-6-5.
2. Clean old sealant from injection pump elbow threads using clean solvent. Dry thoroughly. Start elbow into injection pump adapter, and then apply a light coating of Teflon pipe sealant.
3. Apply a 1/8" (3 mm) bead of silicone rubber sealant in adapter housing grooves. Join components within 15 minutes of bead application. After this time sealant begins to set and its sealing effectiveness may be reduced.
4. Use new "O" ring on injection pump fitting adapter. Purge injector lines by loosening connector 1/2 to one turn and crank engine until a solid stream of fuel flows from connector. Check and adjust injection pump timing.

1. Before removing injectors, clean surrounding area and connections with clean fuel or solvent to prevent contamination. Blow area dry with compressed air. Remove fuel line retaining clamps from lines being removed.
2. Remove and cap line sensor on No. 1 cylinder ("F" Series) and on No. 4 cylinder (Vans) to permit removal of leak-off "T" fitting to fuel filter. Disconnect fuel return hose and position out of way. Cap all open connections.
3. Remove injector and copper gasket from engine. Use "O" Ring Remover (T71P-19703-C) to remove gasket if it is not attached to injector tip. DO NOT strike injector tip against any hard surface during removal.
4. Cap both ends of injector and store in numbered holder or rack in the same way they were removed, such that injector may be installed in original cylinder.

Installation

1. Clean injector bore in cylinder head thoroughly before installing injector. Remove protective cap from tip. Coat threads with anti-seize compound. Install a new copper gasket on injector using a small amount of grease to retain gasket on injector.
2. Install injector into cylinder head bore and tighten. Remove caps from fuel lines and fittings. Install fuel inlet and return "T" fittings on injector. Install 2 new "O" rings on each "T" fitting. Connect fuel line to injectors.
3. Install fuel line retainer clamps and tighten. Purge injector lines if needed by loosening connector 1/2 to one turn and cranking engine until a solid stream of fuel flows from connector. Run engine and check for fuel leaks.

Removal & Installation

1. Disconnect negative battery cables. Drain fuel from filter. Remove water drain tube from bottom of filter assembly. Unscrew and remove water separator drain bowl. Unscrew filter element.
2. Clean gasket surface from adapter to prevent contamination. Lightly coat filter sealing gasket with clean fuel. NOTE: Manufacturer does not recommend adding fuel directly to fuel filter to avoid contamination.
3. Screw new filter onto adapter until seal contacts flange. Tighten filter another 180-300 degrees. Install water drain tube. Clean any fuel spills and connect battery cables. Start engine and check for leaks.

Scheme 15

1. Remove fast idle bracket and solenoid from injection pump. Loosen 3 nuts attaching fuel injection pump to pump mounting adapter with Injection Pump Wrench (T86T-9000-C).
2. Install Injection Pump Rotator (T83T-9000-C) on front of pump. Rotate pump to align injection pump mounting flange timing mark with pump mounting adapter timing mark. (Scheme 15)
3. Remove rotator and tighten mounting nuts. Visually check timing to ensure marks are still aligned after tightening nuts. Install fast idle bracket and solenoid.

Scheme 16

1. Start and warm engine to normal operating temperature. Coolant temperature MUST be 192-212°F (89-100°C) to obtain correct dynamic timing. Stop engine and connect Dynamic Timing Meter (078-00200). Install magnetic pick-up into timing probe hole until pick-up almost touches vibration damper. (Scheme 16)
2. Install Timing Meter Adapter (078-00201) clamp to line pressure sensor on No. 1 injector nozzle ("F" Series) or No. 4 injector nozzle ("E" Series) and connect to timing meter.
3. Connect dynamic timing meter to battery and dial in MINUS 20 degrees offset on meter. Disconnect cold start advance solenoid connector from solenoid terminal.
4. Raise and support rear wheels. Place transmission in Neutral and start engine. Using Throttle Controller (D83T-9000-E), set engine speed at 2000 RPM with no accessory load. Read injection timing on meter.
5. Injection timing should be 8.5 degrees BTDC at 2000 RPM. Apply 12 volts to cold start advance solenoid terminal. NOTE: After voltage is applied to cold start advance solenoid, engine speed may increase. Adjust throttle control to 2000 RPM.
6. Check timing at 2000 RPM. Timing should be advanced one degree before timing specification. If timing advance is less than one degree, replace fuel injection pump top cover.
7. If injection timing is not within 2 degrees of value, injection pump timing must be adjusted. Turn engine off. Note timing mark alignment. Remove fast idle bracket and solenoid from injection pump. Use an Injection Pump Wrench (T86T-9000-C) to loosen pump retaining nuts (keep nuts snug.)
8. Using Injection Pump Rotator (T83T-9000-C), rotate pump clockwise to retard timing or counterclockwise to advance timing (as viewed from front of engine).
9. Moving timing mark.030" (.75 mm) is equal to 2 degrees of timing. Retighten nuts. Start engine and recheck timing. Repeat step 7 as needed to obtain correct timing. Remove timing meter and other test equipment.

COLD (FAST) IDLE RPM

1. Start and run engine until it reaches normal operating temperature. Place transmission in Neutral (M/T) or Park (A/T). Disconnect wiring harness from fast idle solenoid.
2. Apply 12 volts to solenoid to activate it. Increase engine speed momentarily to set solenoid plunger. Fast idle speed should be as specified. Adjust fast idle speed if necessary by turning solenoid plunger. (Scheme 18) COLD (FAST) IDLE RPM Application RPM 7.3L 800-850

Scheme 17

1. Start and run engine until it reaches normal operating temperature. Place transmission in Neutral (M/T) or Drive (A/T). Ensure idle speed adjusting screw is against stop. If not, adjust accelerator linkage.
2. Using Photoelectric Tachometer (099-00001), set curb idle speed to specification indicated on Emission Control Label. Use idle speed screw on side of injector pump for adjustment. (Scheme 17)
3. With transmission in Neutral (M/T) or Park (A/T), increase engine speed momentarily. Shift back into specified gear and recheck idle speed. Readjust if necessary.

VACUUM REGULATOR VALVE

The vacuum regulator valve provides vacuum signals to control automatic transmission shift points. Vacuum setting of valve should be checked periodically, using the following procedure. Engine MUST NOT be running during this procedure.

Scheme 18

Scheme 19

1. Disconnect 2-port vacuum connector from vacuum regulator valve, located on left side of injection pump. (Scheme 19) Remove throttle cable from pump throttle lever, located on right side of pump.
2. Remove throttle return spring and reposition. Place end of spring over throttle lever ball stud and other end over throttle cable support bracket. Attach a hand-held vacuum pump to upper port of vacuum regulator valve.
3. Attach vacuum gauge to lower port (labeled "TRANS") of regulator valve. (Scheme 18) Apply and maintain 20 in. Hg to vacuum regulator valve. It will be necessary to increase vacuum as regulator valve bleeds off.
4. Cycle throttle lever 5 times from idle to wide open throttle with vacuum applied. Insert Gauging Block (T83T-7B200-AH) between pump boss and wide open throttle stop. (Scheme 19)
5. Repositioned spring should hold throttle lever stop against block. Vacuum gauge attached to regulator valve should indicate 6-8 in. Hg. If not, adjust regulator valve.
6. To adjust valve, loosen vacuum regulator valve screws and rotate valve until vacuum gauge reads 7 in. Hg. Tighten screws. If valve cannot be adjusted to specification, replace regulator valve and repeat adjustment procedure.
7. Remove gauging block. Reconnect throttle return spring in original position and connect throttle cable. Apply 20 in. Hg to vacuum regulator valve. While maintaining vacuum, cycle throttle lever 5 times from idle to wide open throttle.
8. Vacuum gauge must indicate at least 13 in. Hg with throttle at idle. If reading is less than 13 in. Hg, replace vacuum regulator valve and repeat adjustment procedure. If reading is correct, remove vacuum pump and gauging block. Attach vacuum connector.

FUEL/WATER SEPARATOR

Water separator should be drained every 5000 miles or when warning light glows. Diesel fuel can damage asphalt and painted surfaces. Always place a drain pan under conditioner to collect fuel. To drain conditioner, use the following procedure

1. Stop vehicle and turn engine off. Open drain valve located under fuel filter water separator. Allow fuel to drain for about 15 seconds or until water is completely drained. Tighten and ensure drain valve is fully closed or seated.
2. Restart engine and check warning light. If warning light continues to glow, fuel system needs to be checked or repaired. The only serviceable item on the separator is the water level sensor.

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

See also:
• GLOW PLUG SYSTEM & DIAGNOSIS
• ENGINE PERFORMANCE DIAGNOSIS
• FUEL/WATER SEPARATOR