Leakage Test

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Open tester shutoff valve 3/4 to 1 3/4 turns from 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.
A drop may form on end of injector nozzle, but should not fall off within a 10 second period. Replace injector nozzle if a drop of test fluid falls from tip during 10 second period. See Fig 1. Release tester pressure.

Fig 1: Injection Nozzle Leakage Test (6.5L Diesel)

Courtesy of GENERAL MOTORS CORP.