TM 5-2420-230-24-2
Engine Run-in (Engine Dynamometer) (014-006)
B3.9 and B5.9 Series Engines
Page 14-20
Section 14 - Engine Testing - Group 14
CAUTION
Do not operate the engine at idle speed longer than
specified during engine run-in. Excessive carbon de-
posits will form in cylinders, causing damage to the
engine.
Operate the engine at approximately 700 rpm for 3 to 5
minutes.
Listen for unusual noise; watch for coolant, fuel, and lu-
bricating oil leaks.
Check for correct engine operation.
NOTE: Repair all leaks or component problems before
continuing the engine run-in.
Move the throttle to obtain 1200-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 70C [158F].
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 and within specification.
L-1318
