Section 14 - Engine Testing - Group 14 Engine Run-In Procedure - Chassis Dynamometer (14-04) M11 Page 14-47 Refer to the Engine Dynamometer Worksheet in this sec- tion. Intake manifold pressure (turbo boost) must be corrected for variances due to intake air temperature. Use the ‘Boost Pressure Correction Factors’ explained in ‘‘Engine Test- ing - General Information’’. It is recommended to monitor block coolant pressure during run-in to aid in early indication of a cooling system problem. Obtain CPL number from the engine dataplate and the fuel pump code from the fuel pump data plate.
Engine performance specifications and fuel system cali- bration values are listed for specific engine CPL and fuel pump codes in the following publications: 1. Fuel Pump Calibration Values, Bulletin No. 3379352. 2. Injector Parts Flow and Cross Reference, Bulletin No. 3379664. 3. Engine Data Sheets If a sudden increase in blowby occurs, or if blowby ex- ceeds the maximum allowable limit during any run-in, return to the previous step and continue the run-in. If blowby does not reach an acceptable level during the next step, discontinue the run-in and determine the cause. Do not proceed to the next step until a steady, acceptable blowby reading is obtained. NOTE:
Blowby must be measured by using Service Tool, Part No. 3375150 or 3822566 with manometer, Part No. ST-1111-3, or equivalent. Service Tool, Part No. 3375150, as shown, utilizes a chamfered 7.67 mm [0.302 in] orifice. Move the throttle to obtain 1200 RPM engine speed, and apply a test load sufficient to develop 25 percent fuel rate. Operate the engine at this speed and load level until the coolant temperature reaches 71°C [160°F]. Check all gauges and record the data.