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Injection Nozzles

NOTE: When testing, use clean test oil or filtered diesel fuel only. Never place hand in front of jet nozzle.
  1. Prior to testing, check longitudinal bore for free passage. Clean with a .007" (.18 mm) diameter wire.
  2. Using Bosch Injector Tester (EFEP 60 H), pump 5 times through injection nozzle on tester. Test buzzing of nozzle by slowly actuating hand lever (about one stroke per second).
  3. During short, fast partial strokes (at least 2 strokes per second) the pintle should be closed. Generate initial jet by moving hand lever slowly in downward direction (4-6 strokes). A vertical cord-like jet should come out of center bore.
NOTE: On new nozzles it is difficult to generate an initial jet. Check longitudinal bore with cleaning needle of .007" (.18 mm) diameter for free passage.
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