Chassis Dynamometer (14-03) Section 14 - Engine Testing - Group 14 M11 Page 14-44 Charge Air Cooler Restriction Measure the intake pressure drop across the charge air cooler. This test can be done with a mercury manometer or two separate gauges, Part No. ST-1273. If two gauges are being used, calibrate both gauges on a common pressure source to ensure consistency. Install one pressure gauge, Part No. ST-1273, in the fitting in the turbocharger compressor outlet elbow. Install the other pressure gauge in the fitting in the intake manifold.
CAC Restriction mm Hg in Hg 152 MAX 6 When measuring the pressure drop, operate the dyna- mometer at the rpm that delivers the maximum horse- power of engine tested. Engine speed will be 1600-1700 rpm on most engines. Intake Air Restriction Measure the inlet air restriction. Install the vacuum gauge, Part No. ST-434, or a manometer in the intake air piping. NOTE: The gauge adapter must be installed at a 90 degree angle to the air flow in a straight section of pipe at a minimum of one pipe diameter before the turbocharger. Operate the engine at maximum horsepower RPM and advertised horsepower and RPM. Observe the reading on the gauge or manometer.
Intake Air Restriction mm H 2 0 in H 2 0 635 MAX 25