TM-9-2815-202-34 Technical Manual for 8V71T Engines for M109 Howitzer Download
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TM 9-2815-202-34 4-40. FUEL INJECTOR ASSEMBLY REPAIR (Cont) (13) (14) (15) (16) (17) Spray tip (a) (b) Check spray tip (33) for cracks, enlarged spray holes, corrosion on outside diameter taper, and oxide scale on spray hole end. Check nut to tip sealing surface and lapped sealing surface for scratches. Do not reuse if there is scale, cracks, or enlarged spray holes. Measure thickness of spray tip shoulder. Minimum thickness is 0.199 inch. Needle valve Check spray tip needle valve for erosion at seat shoulder, scratches, and overheating. Needle valve lift Using needle valve height gage (32), measure needle valve lift as follows: (a) Zero indicator by placing bottom surface of plunger assembly on a flat surface and zero indicator dial. (b) Place spray tip and needle valve assembly (13) tight against bottom of gage with quill of needle valve in hole in plunger. (c)While holding spray tip and needle valve assembly (13) tight against gage (32), read needle valve lift indicator. Lift should be 0.008 to 0.018 inch. If tip assembly exceeds 0.018 inch, replace it. If less than 0.008 inch, inspect tip assembly for foreign material between needle valve and tip seat. Nut Check nut (11 ) for damaged threads, condition of seal ring seating area, and condition of spray tip seating area. Check spray tip hole for corrosion. Spill deflector Inspect ends of deflector (19) for sharp edges or burrs. 4-228 Change 1