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Injection Nozzle Testing

WARNING: Always wear appropriate approved safety glasses when performing injector test. Use only liquid approved for use in tester, SAE calibration No. 208629 (SAE J968D or ISO 4113). Keep hands and other body parts away from nozzle being tested. The liquid discharged leaves the nozzle tip with sufficient force to penetrate the skin and cause serious injury. Nozzle tip should be enclosed in a transparent receptacle if available.
  1. Prepare Test Stand (014-003000) for making test according to manufacturers instructions. Fill test stand reservoir with clean calibration fluid. Open tester valve slightly and operate tester handle to expel air from tester and outlet pipe. Operate tester until solid fluid (without bubbles) flows from end of outlet pipe. Close tester valve.
  2. Connect injection nozzle to test stand. Care should be taken to avoid cross-threading. Tighten connector nut securely. Bleed air from nozzle. Open tester valve and operate tester handle for 8-10 quick strokes to expel air (bleed) from injection nozzle. Fluid should discharge from spray hole in nozzle tip.
  3. Check nozzle opening pressure. Close pump valve and operate pump handle in slow even strokes to bring system up to pressure. Record highest pressure reached before nozzle opens. Repeat operation, increasing pump handle speed if necessary to establish consistent readings. A new nozzle should open at 1800-1950 psi. (126.56-138.51 kg/cm2 ). A used nozzle should open at minimum 1425 psi. (100.19 kg/cm2 ).
  4. Check for tip leakage. Blow nozzle tip dry with filtered compressed air. Operate test pump to maintain pressure at approximately 200 psi (14.06 kg/cm2 ) below opening pressure obtained in step 3). Wetting of nozzle tip is acceptable as long as a drop does not fall within 5 seconds.
  5. After testing is completed, make sure to open pump valve to release built up pressure. Remove nozzle and cap tip and inlet. If nozzle passes opening and leakage test, it is suitable for further service in engine. If nozzle does not pass both tests, replace nozzle.
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