TM-9-2815-200-35 Maintenance Manual for AVDS-1790-2M AVDS-1790-2A and AVDS-1790-2AM Engines Download
Page 548 of 779
Figure 8-3. Mean performance curve. f. Acceptance Test. Repair all fuel and oil leaks at start of test. Check again before engine is removed from stand. At completion of test run, check acceleration, idle, idle oil pressure, and operation of governor. Acceleration should be checked with a moderate steady throttle movement. If engine power is outside limits, check for cause and make correction. Gross corrected horsepower shall be maintained between 735 and 765 horsepower. The governor shall be adjusted to limit the engine speeds as follows: (1) Low idle - 675 to 725 rpm. (2) High idle (no load) - 2640 rpm maximum. g. Overhaul/ MWO Engine Data Plate. After engine is overhauled, install overhaul/ MWO data plate o n engine as outlined in TB ORD-1030. h. Engine Storage. After engine has suc- cessfully completed the acceptance test the engine is to be stored or shipped in accordance with instructions provided in section II of this Chapter. 8-5. Engine Test and Adjustments a. Oil Pressure. Oil pressures shall be measured in accordance with paragraph 8-1i, (1) and (2). The oil pressure regulator valve (D, fig. 6-104) is adjustable, within limits, by the ad- dition or removal of washer-type shims (A) between relief valve cover and spring. Add shims to increase pressure and remove shims to reduce pressure. When oil pressure cannot be adjusted to within the 40-70 psi range, in this manner. replace valve spring (C). Note. Do not add more than three shims, When oil pressure still does not fall within limits specified, replace faulty valve. b. Fuel Pressure. Install a pressure gage in place of the pipe plug (fig. 8-1) in the top, center of the secondary fuel filter and / or water separator to check fuel pressure. Fuel pressure should be adjusted to 40 psi by turning adjusting screw of the fuel pump (fig. 8-1). Turn screw clockwise to increase pressure and coun- terclockwise to decrease pressure. Refer to TM 9-2910-213-34 for further information on the fuel pump. c. Idle Speed. Adjust for smooth idle at 675 to 725 rpm by turning idle adjusting screw (D, fig. 4-85). Turn screw clockwise to increase idle speed and counterclockwise to decrease idle speed. d. Throttle Control Linkage. Normal pin travel on the vehicle control lever is ap- proximately 3 / 16 inch from the stop at both the idle position and the full throttle position. W hen the pin travel is more or less than 3 / 16 inch without spring movement, adjust rod to bring within limits specified (fig. 4-85). e. Manifold Heater. Pump fuel into the engine using a purge pump and press heater button. If heater is operative, heat will be felt at intake manifold turbosupercharger tube (feel intake manifold turbosupercharger tube with hand). When no heat is felt, check harness and heater spark plug for faulty connections. Inspect purge pump and heater nozzle for proper operation. Repair faulty connections or replace purge pump or heater nozzles. f. Oil Consumption Check. (1) Inspect engine for oil leaks. (2) Operate engine until normal operating temperature is reached (180°F). (3) Idle engine for five minutes to allow oil level to stabilize. Check oil level with engine idling, When necessary, add oil to bring level in oil pan to full level, as indicated on level gage. (Refer to applicable Lubrication Order.) (4) Operate engine for 1-1 / 2 hours at 2400 rpm and maximum horsepower. (5) Idle engine for five minutes to allow oil level to stabilize. (6) Check oil level, with engine idling, using oil level gage. 8-6