BELT-SERPENTINE 3589975 - Caterpillar

timing of the engine components should be checked when both of the following situations exist:
The service technician has determined that the fuel delivery to the engine components is not a problem.
The engine operation is erratic or unsatisfactory.Several timing adjustments are required to be certain that the fuel is delivered to the cylinders in the correct amounts, the correct sequence, and the correct time. The following adjustments and procedures can be used to determine that the fuel system is operating correctly. Follow the procedures carefully, because each procedure depends on the other procedure for good engine operation.
The camshafts must be in time with the crankshaft.
Fuel injectors should be adjusted to the same timing dimension in order to prevent the advancing or the retarding of engine timing.
The timing dimension is the distance from the top of the fuel injector spring's retainer to the top of the fuel injector body's base. If the timing dimension is longer than the gauge block's setting, the fuel injector's plunger must be pushed in farther. The fuel injector's plunger must be pushed in farther in order to close the bypass. When the bypass is closed, fuel injection begins. This will retard the timing. If the timing dimension is shorter than the gauge block's setting, the plunger must be pushed in a shorter distance in order to close the bypass. Fuel injection will start sooner in the engine's cycle, so the timing will be advanced.
The fuel control linkage must be set to a reference position. This reference position is the starting point for other adjustments.
The fuel system linkage is in the reference position when the synchronizing pin is installed and the fuel system linkage is advanced. When the above two conditions are met, the flat surface on the rack's fuel stop lever is positioned against the pin.
The fuel injector racks must be set so that the fuel injectors are synchronized. The fuel injectors are synchronized when each fuel injector sends the same amount of fuel to each combustion chamber.
The governor's fuel control rod and the governor's linkage should be set to a reference position.
The fuel setting should be checked and adjusted, if necessary.