SCREW-ADJUSTMENT 9S4980 - Caterpillar

Table 1
Tools Needed
8T-2684 Rack Synchronization Gauge 1 Injector synchronization is the setting of all fuel injector racks to a reference position so each injector gives the same amount of fuel to each cylinder. Injector synchronization is done by setting each fuel injector rack to the same position while the control linkage is in a fixed position. Use the following procedure for the adjustment of injector synchronization:
Illustration 1 g00323443
Location of fuel setting cover and synchronization pin (typical example)
(1) Plug
(2) Synchronization pin
(3) Cover
The top bolt that holds cover (3) in position is synchronization pin (2). Remove synchronization pin (2) and plug (1) from the front drive housing. DO NOT destroy the seal or remove cover (3).
Remove the washer from the synchronization pin. Remove the plug and install the synchronization pin into the threaded hole. Tighten the synchronization pin.
Illustration 2 g00323444
Position of the synchronization pin (typical example)
(2) Synchronization pin
(4) Fuel stop lever
Turn the governor or the actuator terminal shaft to the fuel ON position until the flat face of fuel stop lever (4) contacts synchronization pin (2). This is the synchronizing position or zero reference point. Hold the control linkage in this position when the injectors are adjusted.
Remove the valve covers.
Illustration 3 g00323446
Location for gauge and control rod adjustment (typical example)
(5) 8T-2684 Rack Synchronization Gauge
(6) Control rod
With the fuel stop lever against the synchronization pin, put the 8T-2684 Rack Synchronization Gauge (5) on the round part of the fuel injector rack between the fuel injector body and the end of the rack. Use a screwdriver and make an adjustment of control rod (6). Turn the screw that is located on the control rod one click at a time until the 8T-2684 Rack Synchronization Gauge fits between the fuel injector body and the shoulder at the end of the rack. Remove the screwdriver from the control rod so that no pressure remains on the linkage. Check the setting with the rack synchronization gauge. Any pressure on the linkage with the screwdriver will not give a correct indication when the setting is checked with the rack synchronization gauge. Ensure that the linkage is free and that the linkage is giving an accurate setting by moving the linkage. Check the setting again. Put the box end of a combination wrench over the nut and the bolt. The nut and the bolt connect control rod (6) and the bellcrank. Pull upward on the control rod three times. Check the setting again.
Illustration 4 g00323448
Gauge in place on the fuel injector rack (typical example)
(5) 8T-2684 Rack Synchronization Gauge
(7) Fuel injector rack
If the other injectors need to be adjusted, use rack synchronization gauge (5). When all adjustments have been made, release the actuator terminal shaft.
Illustration 5 g00323450
Adjustment of fuel control rod (typical example)
(5) 8T-2684 Rack Synchronization Gauge.
Install the valve covers.
Check the fuel setting and perform any necessary adjustments. Refer to Testing And Adjusting, "Fuel Setting" for this procedure.