C15 On-Highway Engine Caterpillar

Note: For the SDP engines, it is not necessary to remove the variable valve actuators.

Illustration 1	g01192268
Injector Mechanism (1) Rocker arm (2) Adjustment screw (3) Locknut

To make an adjustment to the unit injectors on cylinders 3, 5, and 6 use the following procedure:

1. Put the No. 1 piston at the top center position on the compression stroke. Refer to Testing and Adjusting, "Finding Top Center Position for No. 1 Piston".

2. Turn unit injector adjustment screw (2) clockwise until contact with the unit injector is made.

3. Tighten the adjustment screw to an additional 2 turns.

4. Turn the adjustment screw counterclockwise for 2.5 turns.

5. Turn the adjustment screw until the screw makes contact with the electronic unit injector.

6. Turn unit injector adjustment screw (2) clockwise for an additional 180 degrees.

7. Hold the adjustment screw in this position and tighten locknut (3) to a torque of 100 ± 10 N·m (74 ± 7 lb ft).

8. To make an adjustment to the unit injectors on cylinders 1, 2, and 4, remove the timing bolt. Turn the flywheel by 360 degrees in the direction of engine rotation. The direction of engine rotation is counterclockwise, as the engine is viewed from the flywheel end. This will put the number 1 piston at the top center position on the exhaust stroke.

9. Repeat Steps 5 through 7.

10. Remove the timing bolt from the flywheel after all the unit injector adjustments have been made. Reinstall the valve mechanism cover.