TESTING AND ADJUSTING MEASURING AIR SUPPLY PRESSURE (BOOST PRESSURE) MEASURING AIR SUPPLY PRESSURE (BOOST PRESSURE) When removing or installing the measuring equipment or when carrying out the measure- ments, be careful not to touch any high tem- perature parts or rotating parts. 1. Remove air supply pressure measurement plug (1) (PT 1/8), then install the nipple C2 . 2. Connect the oil pressure measurement hose to the coupler and pressure gauge F (–101.3 to +200 kPa {–760 to +1500 mmHg}). Note: Run the engine at a mid-range speed or above, and use the self-seal portion of the gauge to bleed the oil from inside the hose.
Insert the gauge about half way, and repeatedly open the self-seal portion to bleed the oil. fl The gauge does not work if there is any oil inside the hose, so always be sure to bleed all the oil. 3. Run the engine at near the rated speed and measure the pressure indicated by the gauge. fl Near rated output Run the engine at near the rated output. For details, see the measurement of the engine speed when the arm IN circuit is relieved in the H/O mode and power max. mode. fl The air supply pressure (boost pressure) should be measured with the engine running at rated output. However, when measuring in the field, a similar value can be obtained with the above conditions. 20-112 PC400, 450-6