The engine run-in period allows the tester to detect assembly errors and to make final adjustments needed for
performance that meets specifications.
NOTE: The amount of time specified for the following engine run-in phases are minimums. Additional time can be used, if desired, at each phase except engine idle periods.
Measurements from these indicators and gauges must be observed closely during all phases of the engine run-in
period. Refer to page 8-6 for specifications and acceptable readings.
To correctly evaluate the engine performance, this additional measurement must be observed during engine
run-in phases.
It is good practice to observe these measurements even if engine performance meets specifications. If engine performance does not meet specifications, these measurements can indicate possible reasons for under-performance.
Caution: Do not crank the engine for more than 30 seconds. Excessive heat will damage the starting motor.
Crank the engine and observe the lubricating oil pressure when the engine starts. If the engine fails to start within
30 seconds, allow the starting motor to cool for 2 minutes before ranking the engine again.
Engine lubricating oil pressure must be at least 69 kPa [10 psi] at 700 RPM.
Caution: If the lubricating oil pressure is not within specifications, shut off the engine immediately. Low lubricating oil pressure will cause engine damage.
Correct the problem if the lubricating oil pressure is not within specifications.
Caution: Do not operate the engine at idle speed longer than specified during engine run-in. Excessive carbon
formation will cause damage to the engine.
Operate the engine at approximately 700 RPM for 3 to 5 minutes.
Listen for unusual noises; watch for coolant, fuel, and lubricating oil leaks; and check for correct engine operation in general.
NOTE: Repair all leaks or component problems before continuing the engine run-in.
Move the throttle to obtain 1,200 RPM engine speed, and set the test load to 25 percent of the rated load.
Operate the engine at this speed and load level until the coolant temperature is 70° C [160° F]. Check all gauges
and record the data.
NOTE: Do not proceed to the next step until a steady blowby reading is obtained.
Open the throttle to the speed at which peak torque occurs, and adjust the dynamometer load to 50 percent of
torque peak load. Operate the engine at this speed and load level for 2 minutes.
Check all gauges and record the data.
NOTE: Do not proceed to the next step until blowby is stable within specifications.
With the engine speed remaining at torque peak RPM, increase the dynamometer load to 75 percent of torque
peak load. Operate the engine at this speed and load level for 2 minutes. Check all gauges and record the data.
NOTE: Do not proceed to the next step until blowby is stable within specifications.
Move the throttle lever to its fully opened position, and increase the dynamometer load until the engine speed is
at torque peak RPM. Operate the engine at this speed and load level for 10 minutes or until the blowby becomes
stable within specifications.
Check all gauges and record the data.
Reduce the dynamometer load until the engine speed increases to the engine’s rated RPM.
Operate the engine at rated RPM for 5 minutes.
Check all gauges and record the data.
Caution: Shutting off the engine immediately after operating at full load will damage the turbocharger and
internal components. Always allow the engine to cool before shutting it off.
Remove the dynamometer load completely, and operate the engine at 700 RPM for 3 to 5 minutes. This period will
allow the turbocharger and other components to cool.
Shut off the engine.
