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.
- 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 manufacturers' instructions for exact tester operating instructions.CAUTION: 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 is 870 psi. When nozzle releases pressure, note spray pattern and compare with examples shown. If incorrect, or if a liquid stream, replace nozzle. See Fig 1.
- 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 slowly to 218 psi BELOW actual opening pressure. Maintain pressure for 5 seconds and compare fuel leakage to examples. See Fig 2.
- Replace defective nozzles, then reinstall all nozzles. Install carefully and tighten to recommended torque.