The diesel engine utilizes an electric glow plug system to aid in the start of the engine. The function of this stem is to pre-heat the combustion chamber to aid ignition of the fuel.
The system consists of eight glow plugs (one for each cylinder), control switch, power relay, after glow relay, wait lamp latching relay, wait lamp and the eight fusible links located between the harness and the glow plug terminal.
On initial start with cold engine, the glow plug system operates as follows: The glow plug control switch energizes the power relay (which is a magnetic switch) and the power relay contacts close. Battery current energizes the glow plugs. Current to the glow plugs and a wait lamp will be shut off when the glow plugs are hot enough. This takes from 2 to 10 second after the key is first turned on. When the wait lamp goes off, the engine is ready to start. After the engine is started the glow plugs begin an on-off cycle for about 40 to 90 seconds. This cycle helps to clear start-up smoke. The control switch (the brain of the operation) is threaded into the left cylinder head coolant jacket. the control unit senses engine coolant temperature. Since the control unit senses temperature and glow plug operation the glow plug system will not be activated unless needed. On a restart (warm engine) the glow plug system will not be activated unless the coolant temperature drops before 165°F (91°C).
Since the fast start system utilizes 6 volt glow plugs in a 12 volt system to achieve rapid heating of the glow plug, a cycling device is required in the circuit.
REMOVAL & INSTALLATION
- Remove the fuel line retaining clamp(s) from the nozzle lines that are to be removed.
- Disconnect the nozzle fuel inlet (high pressure) and fuel leak-off tees from each nozzle assembly and position out of the way. Cover the open ends of the fuel inlet and outlet or nozzles with protective caps, to prevent dirt from entering.
- Remove the injection nozzles by turning them counterclockwise. Pull the nozzle assembly with the copper washer attached from the engine. Cover the nozzle fuel opening and spray tip, with plastic caps, to prevent the entry of dirt.
- Place the nozzle assemblies in a fabricated holder as they are removed from the heads. The holder should be marked with numbers corresponding to the cylinder numbering of the engine. This will allow for reinstallation of the nozzle in the same ports from which they were removed.
- Thoroughly clean the nozzle bore in cylinder head before reinserting the nozzle assembly with nozzle seat cleaner, special tool T83T-9527-A, or equivalent. Make certain that no small particles of metal or carbon remain on the seating surface. Blow out the particles with compressed air.
- Remove the protective cap and install a new copper gasket on the nozzle assembly, with a small dab of grease.
- Install the nozzle assembly into the cylinder head nozzle bore.
- Tighten the nozzle assembly to 33 ft. lbs. (45 Nm).
- Remove the protective caps from nozzle assemblies and fuel lines.
- Install the leak-off tees to the nozzle assemblies.
- Connect the high pressure fuel line and tighten, using a flare nut wrench.
- Install the fuel line retainer clamps.
- Start the engine and check for leaks.