TM-9-2815-220-24 Maintenance Manual for AVDS-1790-2CA AVDS-1790-DA and AVDS-1790-2DR Engines Download
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TM 9-2815-220-24 CYLINDER COMPRESSION TEST 0033 00 TEST (Continued) NOTE High cylinder pressures can be caused by combustion of lubricating oil in the cylinder combustion chamber. If this occurs, allow combustion gases to escape prior to taking compression readings by cranking the engine with the starter for 30 seconds with the fuel supply shut off. 4. After all 12 cylinders are checked, determine the pressure difference between high and low cylinder readings. a. This variation should not exceed 70 psi. (483 kPa). b. If compression readings are below the low limit of 330 psi (2,275 kPa), the engine motoring rpm should be checked to be sure that it is 140 to 180 rpm. c. Compression should be checked again to confirm the previous readings before submitting an engine for overhaul. AFTER TEST 1. Remove gauge assembly (3) from compression adapter (2). 3 2 WP 0033 00-3