•WARNING• Diesel fuel is flammable. Do not perform fuel system procedures near open flame. Injury to personnel may result. NOTE Synchronization is the position of all injector racks in relationship to rack at No. 1 injector. Synchronizing injector racks ensures each cylinder receives the same amount of fuel for combustion. The control linkage is at synchronizing position when injector of No. 1 cylinder is at fuel shutoff. Since No. 1 injector is the reference point for the other injectors, no synchronizing adjustment is made to No. 1 injector. Always synchronize an injector when it has been removed and reinstalled or replaced. If No. 1 injector is reinstalled or replaced, all injectors must be syncronized. TESTING 1. Clean end of rack bars (3) with lint-free cloth. 2. Press top ball on pivot arm of holding fixture fully and hold. CAUTION Bottom contact point on pivot arm of holding fixture must clear end of rack bar when inserted into engine. Failure to do so will cause damage to equipment and result in an inaccurate reading. 3. While pressing top ball on pivot arm, insert holding fixture with dial indicators at No. 1 injector so stabilizing blade seats against intake valve spring (1), and spring clip seats against inside of air intake manifold (2). 4. Push down on holding fixture and listen for a “snap” sound to ensure holding fixture is seated against injector base. 5. Release top ball on pivot arm of holding fixture. Ensure pivot arm contacts face of rack bar (3). 0321 00-2 TM 9-2320-386-24-1-2 0321 00 FUEL INJECTOR SYNCHRONIZATION MAINTENANCE (Contd)