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Leakage Test

  1. Open tester shutoff valve 3/4 to 1 3/4 turns from a closed position. Blow dry injector nozzle tip. Slowly depress tester lever until pressure gauge reads 1400 psi (98 kg/cm2 ). Maintain pressure for 10 seconds and observe injector nozzle tip.
  2. A drop may form on end of injector nozzle, but should not drop off within a 10 second period. Replace injector nozzle if drop of test fluid drops from tip during the 10 second period. See Fig 1. Release tester pressure.
Fig 1: Injection Nozzle Leakage Test
G90A15743Courtesy of GENERAL MOTORS CORP.