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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. Replace injector if drop of test fluid drops from tip. A drop may form but not drop off within specified time period. See Fig 1. Release tester pressure.
Fig 1: Nozzle Leakage Test A drop of test fluid may form but not drop off within 10 seconds. Courtesy of General Motors Corp.
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