Injection Nozzle

Remove injection nozzles. Refer to removal procedure under REMOVAL & INSTALLATION. Clean carbon from tip of nozzle with a soft brass brush. Check torque of inlet fitting to nozzle body and correct as necessary.

Fig 1: Injector Nozzle Spray Patterns Keep spray contained to prevent injury to any body part.
Assemble nozzle to a suitable diesel injection nozzle tester using a connecting line (high pressure) 12" long by 1/4" O.D. by 1/16" I.D. between nozzle and tester. Refer to test equipment manufacturer's instructions for exact tester operating instructions.
WARNING: When testing nozzles, keep spray contained to avoid serious injury. DO NOT allow injector to release line pressure on hands, arms or any part of body. Pressure of atomized test spray has sufficient penetrating power to puncture flesh.
Build nozzle pressure slow enough to determine exact minimum opening pressure of nozzle. Minimum opening pressure for new nozzles on V6 models is 1000 psi (70 kg/cm² ) without color band or with Green color band; 800 psi (56 kg/cm² ) on models with Red color band.
Minimum opening pressure for new nozzles on V8 models is 1225 psi (86 kg/cm² ) without color band or with White collar band. Opening pressure is about 200 psi (14 kg/cm² ) less for all used nozzles.
When nozzle releases pressure, note spray pattern and compare with examples shown in Fig 1 . If incorrect, or if a liquid stream, replace nozzle.
To test nozzle seat for leakage, decrease pressure to at least 290 psi BELOW actual opening pressure. Dry nozzle tip with compressed air, then increase pressure to 150 psi (10 kg/cm² ) BELOW actual opening pressure. Maintain pressure for 5 seconds and compare fuel leakage to examples shown in Figure .
Replace defective nozzles, then reinstall all nozzles. Install carefully and tighten.