TM 5-3895-382-24 NOTE: Extra  care  should  be  used  in  handling  the  fuel injector nozzle in order to prevent damage to the nozzle tip.  A scratch or a burr could cause needle leakage  or  spray  distortion.    Keep  dirt  from  the orifices   in   the   nozzle   tip   which   could   damage engine components or cause spray distortion. Pressure Test Make sure that you wear eye protection at all times during testing.  When fuel injection nozzles are tested, test fluids travel   through   the   orifices   of   the   nozzle   tip   with   high pressure.    Under  this  amount  of  pressure,  the  test  fluid can   pierce   the   skin   and   cause   serious   injury   to   the operator.  Always keep the tip of the fuel injection nozzle pointed away from the operator and into the fuel collector and extension. Illustration 57 5P-4150 Nozzle Testing Group. (8) 5P-7448 Adapter (9) Fuel injector nozzle (10) 6V-2170 Tube (11) 1U-8857 Extension (12) 8S-2270 Fuel Collector (13) 8T-5313 Filter NOTICE Do  not  use  dirty  test  fluids  when  you  test  fuel  injection nozzles.    Also,  do  not  test  fuel  injection  nozzles  unless you have the correct service tools.  The use of dirty test fluids and the use of incorrect service tools will result In damage to fuel injection nozzles. 1. Connect the fuel injector nozzle (9) to the tooling that is shown in Illustration 57. The spray from the fuel injector nozzle must be directed into the 1U-8857 Extension (11) and the  8S-2270  Fuel Collector (12). Refer   to   the   table   in   Specifications,   "Fuel   Injector Nozzles"   for   the   correct   pressure   settings.      If   the opening pressure is not within the range of the setting which is given in the table, the fuel injector nozzle must be replaced. Use  clean   6V-6068   Calibration   Fluid   when   the   fuel injector   nozzles   are   tested.      The   calibration   fluid   is equivalent to SAE J-967 (ISO 4113) oil. 2. Close   the   gauge   protector   valve.      Close   the   shutoff valve.  Open the pump isolator valve.  In order to flush the fuel injector nozzle, operate the nozzle tester for 10 to 15 strokes at a rate of approximately 60 strokes per minute. 3. Open  the  gauge  protector  valve.    Slowly  increase  the pressure until the valve in the fuel injector nozzle opens. Note the highest pressure indication on the dial indicator before the pointer moves to 0 kPa (0 psi).  This highest pressure  indication  is  the  opening  pressure  of  the  fuel injector nozzle.  The opening pressure is defined when the valve needle (16) is lifted from the valve seat. Refer   to   the   table   in   Specifications,   "Fuel   Injection Nozzles"  for  correct  pressure  settings.    If  the  opening pressure  is  not  within  the  range  of  the  setting  that  is given   in   the   table,   the   fuel   injector   nozzle   must   be replaced. Back Leakage Test 1. Connect the fuel injector nozzle (9) to the tooling.  Refer to Illustration 57 for more information. Position the fuel injector nozzle so that the direction of the  fuel  spray  is  into  the  1U-8857  Extension  (11)  and the 8S-2270 Fuel Collector (12). 2. Pump the pressure to about 1030 kPa (150 psi) below the opening pressure of the fuel injector nozzle.  Refer to Specifications, "Fuel Injection Nozzles" for the correct setting  of  the  opening  pressure.    Release  the  handle. When  the  pressure  begins  to  decrease,  note  the  time that    is    required    for    the    pressure    to    decrease    to approximately 0 kPa (0 psi).  If the fuel injector nozzle is not defective, the time will not be less than 5 seconds or more than 45 seconds. If the time that is required for the pressure to decrease to 0 kPa (0 psi) is less than 5 seconds, too much fuel is leaking   around   the   valve   needle.      Replace   the   fuel injector nozzle. 6-67