COMBINATION VALVE GP 9J0773 - Caterpillar

(7PR),
3412E (4CR) Industrial EnginesAll carbon deposits should be removed from the injector sleeve bore and the angled surface of the sleeve before installing injectors in 3408E or 3412E Industrial Engines. Cleanliness is essential to properly seal the injector in the sleeve and to prevent tip damage or injector failure due to leakage of combustion gas into the fuel passage.
The 164-5927 Tube Brush and the 164-5924 Injector Sleeve Bore Gauge are now available. The tube brush is used to clean the injector bore. The injector sleeve bore gauge is used to verify that the bore of the injector sleeve is thoroughly clean. For additional details you can order the Service Tool Announcement, form number NEHG4893.
The 161-3568 Grommet is also now available. Once the injector is installed in the injector sleeve, place a grommet on each of the two posts of the injector solenoid prior to installing the injector wiring harness.
The steps for removing and installing the injectors in 3408E and 3412E Industrial Engines are outlined in Special Instruction REHS0116-02, "Removal And Installation Of HEUI Injectors". Failure to follow the procedures in the Special Instruction, version 02, and to use the gauge to verify the cleanliness of the sleeve bore could result in injector tip breakage and severe engine damage.