TM-9-2815-220-34 Direct Support Manual for AVDS-1790-2C and AVDS-1790-2D Engines Download
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) } ) 3-130. Cleaning, Inspection and Repair a .. Cleaning. Refer to paragraph 3-36. b. I11specfio11 and Repair. Refer to paragraphs 3-37 and 3-38. Refer to paragraph 3-39 when replacing screw thread h1serts. 3-131. Assembly a. Genera.tor Support. (Model AV DS-I 790-2C En- gi ne). Loosely attach generat or cradle (3, figure TM 9-2815-220-34 3-277) to generator cradle angle bracket (9) with two machine screws (6) and flat washers (5). I b. Generator Support. (1Hodel AVDS-1790-2D and AV DS-170-2DR Engines). Loosely attach generator cradle (12) to angle bracket (21) with two screws (18) and flat washers (17). c. Starter Support. Loosely attach starter cradle assembly (14, fig. 3-276) to starter support angle bracket (8) with four screws (9) and flat washers I (J 0). Section XXll. REPAIR OF FUEL BACKFLOW VALVE, PRIMARY FUEL FILTER, FUELATER SEPARATOR, AND ASSOCIATED PARTS 3-132. General I 11lis section covers the repair of the fuel backflow valve, primary fuel filter, fuel/water separator, automatic drain system, and associated parts. Specific instructions on diassembly, cleaning, in- spection and assembly accompany the repair opera- tions. 3-133. Fuel Backflow Valve a. Disassembly. Remove backflow valve outlet adapter (13, fig. 3-278) om fuel backflow valve (29). Remove manifold heater fueJ inlet tube (44, fig. 3-267), and inlet tube adapter (35) from backflow valve inlet tee (39). Remove fuel filter elbow (42) (Model AVDS-l 790-2C only), main fuel supply filter (41) and purge pump inlet tee reducer (40) from rnlet tee (39).Remove backflow vaJve inlet tee (39), and back.flow valve inlet adapter (l 2, fig. 3-278) from backflow valve (29). a.1.' Disassembly. Remove pipe to tube straight adapter (45, fig. 3-278) from fuel backOow valve (46). Remove pipe to tube straight adapter (35) from backflow valve. · b. Cleaning, Inspection and Repair. Refer to paragraphs 3-36, 3-37, and 3-38. Inspect plastic tube (44, fig. 3-267) for inteaJ diameter re- ductfon at tube nut rrule. fnspect tube fittings for stripped or damaged threads. Replace tube if i t is kinked, spUt, or fittings are damaged. Replace tube when inteal diameter is reduced enough to resict fuel flow. When repJacing tube (45, fig. 3-267) install insert tube fittings (46) in both ends of tube. c. Tes/ and A djuslmen t. (1) Fill fuel backflow valve with test fluid, MIL-F-7024A, Type II, and apply a pressure of 1/2 psi to port markedd "FREE FLOW , , (fuel inlet Table 3-27. Deleted. from primary fuel filter). TI1e backflow vaJve must open at tl1is pressure. Valve operation can be determined when fluid flows from the fuel pump outlet port (fig. 3-279). (2) Apply a pressure of 85 to 95 psi to the heater pump inlet port. The check baU must bypass fluid at this pressure. Adjust slotted head adjusting screw to obtain this opening pressure. (3) Plug the fuel pump outlet port, and the heater pulT p outlet port, and apply a pressure of 100 psi at heater pump inlet port. There should be no fuel leakage from the "FREE FLOW" port. (4) If the valve fails to pass either test, replace entire valve assembly. d. Assembly. Install backflow valve inlet adapt- er (12, fig. 3-278) and backflow valve inlet tee (39, fig. 3-267) in backflow valve (29, fig. 3-278). Install pmge fuel supply filter (41, fig. 3-267) and fuel filter elbow (42) (Model AVDS-J 790-2C Engine only) backflow valve inlet tee (39) with purge pump inlet tee reducer (40). Install htbe adapter (35), a11d manifold heater fuel inlet lube (44) in backflow valve inlet tee (39). Install back!low valve outlet adapter (13, fig. 3-278). d.J. Install pipe to tube straight adapter (35, fig. 3-278) in backflow vaJve (46). Install pipe to tube straight adapter (45) in backflow valve. 3-134. Primary Fuel Filter a. Disassembly. (I) Remove fuel nJter outlet elbow (JO, fig. 3-278), and constant bleed adapter (10, fig.3-282) from primary filter. Loosen two self- locking nuts (26) and remove primary filter (11) from filter bracket (25). Change 3 3· 185