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Auxiliary engine fuel injector overhaul

Shut air starting valve, close fuel inlet & outlet and isolate the system. Lube oil priming pump is run for 30mints and stopped. Remove lock nut of high pressure pipe remove high pressure pipe. Remove injector using the tool. Keep the injector on the test kit and perform various test like atomization, lifting pressure
pressure falling steady and dripping. put the injector in vice a tighten in between soft jaws. remove lock nut, compression nut and relive spring pressure and take out spring. Open cap-nut and take out needle and guide. the spring can be checked by dropping it on the ground, compressing in a vice and checking for cracks.there should not be any scoring.insert the needle in the guide and it should go by its own weight. then check the nozzle holes using Go NO Go gauge. then set lifting pressure by adjusting compression nut. perform all previous tests again. Fuel injector test  atomization test-fuel handle is pushed hard two or three times to see the injection pattern. Dribbling test: maintain fuel oil pressure 10 bar below the opening pressure and check fuel nozzles for dribbling. spray pattern test- the test bench has a hole plate, spray can enter into hole without touching any hole.

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