TM-9-2815-220-34 Direct Support Manual for AVDS-1790-2C and AVDS-1790-2D Engines Download
Page 185 of 532
Figure 2-1�9. l 11stnlli11n or removing compression apter. iqure 2-150. Checking cylinder compression. e. Co1111>1·11.i1111 Vuriafio11. After all 12 cylinders are checked, determine lhe pressut'e difference be- tween high and low cylinder reading. This varia- tion should not exceed 70 psi. 1f compression read- ings are below the low limit of 330 psi, the engine motoring RPM should be checked to be sure that it is 140 to 180 RPM. Compression should be checked again to confirm the previous readings before submitting an engine for overhaul. Remove com- pression gage from adapter. Remove adapter and gasket (fig. 2-14 9). Discard gasket. TM 9·2815·220·34 f. Assembly. Install fuel injector nozzle and holder assemblies, paragraph 2-48b. Install fuel injector tubes, paragraph 2-21b. Install oil coolers, cooling fan shroud, engine upper covers, cooling fans and cooling fan vanes, refer to paragraph 2-27b and paragraph 2-21b. 2-52. Adjusting Intake and Exhaust Valve Clearance a. Disassembly. (1) Remove cooling fan vanes, cooling fans, enne upper covers, cooling fan sht'oud and fuel injector tubes. Refer to paragraph 2-2lu. (2) Remove oil coolers. Refer to paragraph 2-27a. (3) Remove two self-locking bolts (1, fig. 2-151) support (2), and access cover (3). Remove and dis- card gasket (4). Remove two machine bolts (5) and two nat washers (6) and remove access cover \7). Remove and discard gasket (8). NOTE All of the valve adjusting screw acc�ss covers are removed or installed in the same manner. 1 Self-locking bolt 2 Support 3 Access cover 4 Gasket 5 Machine boll 6 Flat washer 7 Access cover 8 Gaskel Figure 2-151. Rem+t1i11g or inatafli+g valve adjusting screw access cover. NOTE Before checking or adjusting exhaust and/or intake valve clearance, make sure both valves are closed on the cylinder being checked. Turn crankshaft as shown Change 2 2·96.1