NMWR-9-2815-220 Overhaul Manual for M60 M88 Engine AVDS-1790-2CA, AVDS-1790-2DA, AVDS-1790-2DR Download
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NMWR 9-2815-220 OIL PUMP ASSEMBLY OVERHAUL—Continued 0013 00 RECLAMATION – Continued (e) Pre-heat shaft 150° F (66° C) to 200° F (93° C) with thermospray or plasmaspray gun. (f) Using a Metco 6P Thermospray or MB Plasmaspray System in accordance with manufacturer’s printed instructions, apply Metco 501 self-fusing molybdenum powder to a thickness of approximately 0.005 in. (0.127 mm) per side over the drawing finish dimension to allow for finish grinding. (g) Using an external grinder with a 60 grit green silicon carbide wheel and water base with rust inhibitor, finish grind coated bearing surfaces to drawing specifications (DWG 11683960). NOTE This item cannot be purchased separately. (h) All mounting surfaces repaired by this process shall be 100% inspected for coating integrity after machining. The coating shall show no bond separation at the coating to base metal interface. The coating shall be free from blistering, cracking, chipping, and frayed edges. There shall be no bleedout of oil or other contaminants through the finished coating. 4. Oil pump impeller driven shaft (part no. 11683945). Reclaim worn bearing surfaces by metalspray. Refer to Table 18 (OIP 11683945). NOTE To demonstrate proficiency and attain certified status, an operator shall flame spray a test piece in accordance with this specification which shall be destructively and metallographically examined to assure bond integrity and coating soundness. To maintain certified status, an operator must consistently produce acceptable repairs relative to the flame sprayed coating and pass a yearly destructive examination for bond and coating integrity. (a) Place shaft in lathe. When using Metco 10E or 12E Wire Spray System, undercut bearing surfaces by 0.035 in. (0.889 mm). When using Metco 6P Thermospray System, undercut the bearing surfaces as required to eliminate surface defects but not to exceed 0.035 in. (0.889 mm) (Figure 3). (b) Thoroughly clean and degrease shaft with trichloroethylene degreaser. Figure 3. Oil Pump Impeller Driven Shaft Bearing Surfaces. 0013 00-6 Change 1