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Leakage Test

  1. Open tester shutoff valve an additional 1/2 to 1 1/2 turns. Blow dry nozzle tip. Slowly depress tester lever until pressure gauge reads 1400 psi (98 kg/cm2 ). Maintain pressure for 10 seconds and observe nozzle tip.
  2. A drop may form on end of injector, but should not drop off within a 10 second period. Replace injector if drop of test fluid drops from tip during the 10 second period. See Fig 1. Release tester pressure.
Fig 1: Nozzle Leakage Test
G9778Courtesy of GENERAL MOTORS CORP.