TM-9-2815-202-34 Technical Manual for 8V71T Engines for M109 Howitzer Download
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TM 9-2815-202-34 (i) (j) WARNING Do not operate diesel fuel injector nozzle tester without shield. Fuel spray can penetrate skin. Fuel oil entering blood stream may cause serious infection. Place shield (43) on diesel fuel injector nozzle tester (41). Operate pump handle (40) with smooth even strokes and record fuel injector needle valve opening pressure (pop pressure). Needle valve opens when fuel sprays from tip. Pop needle valve several times to purge air from system. Record test gage (44) opening pressure. Final needle valve opening pressure must be 3450-4050 PSI. Remove injector nut (11), spray tip (33), needle valve (35), spring (16), spring seat (15), spring cage (14), check valve cage (17), and check valve (18) from mounting pedestal (42). NOTE After needle valve opening pressure test is complete, continue injector assembly [ref. step e.(13)]. (6) Needle Valve Holding Pressure (a) Place fuel injector in fixture (38). (b) Operate pump handle (39) to bring pressure up to 2200 PSI. NOTE Pop fuel injector several times with popping handle (39) until no pressure is observed on injector test fixture (41) before removing injector from test fixture to avoid fuel spray as injector is removed from fixture. (c) Close fuel shut off valve. Start timing when pressure reaches 2000 PSI and stop at PSI. Minimum time is 20 seconds. 1500 (d) If pressure drops in less than 20 seconds, check for leaks around spray tip, seal ring, and fuel connectors. END OF TASK FOLLOW-ON MAINTENANCE Para Description 5-37 Install injectors (7083-7391, 7083-7396, and 7083-7399) 4-38 Install injectors (7083-7395 and 7083-7398) Change 1 4-234.1/4-234.2 Blank