DETROIT DIESEL 53
Run-In Instructions 13.2.1
power absorbed in a water brake type dynamometer, as an example, is governed by the volume of fluid within the
working system. The fluid offers resistance to a rotating motion. By controlling the volume of water in the absorption
unit, the load may be increased or decreased as required.
The power absorbed is generally measured in torque (lb-ft) on a suitable scale. This value for a given engine speed will
show the brake horsepower developed in the engine by the following formula:
BHP = (T x RPM)/5250
BHP = brake horsepower
RPM = revolutions per minute
Some dynamometers indicate direct brake horsepower readings. Therefore, the use of the formula is not required when
using these units.
During the actual operation, all data taken should be recorded immediately on an Engine Test Report (see sample on
Certain instrumentation is necessary so that data required to complete the Engine Test Report may be obtained. The
following list contains both the minimum amount of instructions and the proper location of the fittings on the engine so
that the readings represent a true evaluation of engine conditions.
a. Oil pressure gage installed in one of the engine main oil galleries.
b. Oil temperature gage installed in the oil pan, or thermometer installed in the dipstick hole in the oil pan.
c. Adaptor for connecting a pressure gage or mercury manometer to the engine air box.
d. Water temperature gage installed in the thermostat housing.
e. Adaptor for connecting a pressure gage or water manometer to the crankcase.
f. Adaptor for connecting a pressure gage or mercury manometer to the exhaust manifold at the flange.
g. Adaptor for connecting a vacuum gage or water manometer to the blower inlet.
h. Adaptor for connecting a fuel pressure gage to the fuel manifold inlet passage.
i. Adaptor for connecting a pressure gage or mercury manometer to the turbocharger.
In some cases, gages reading in pounds per square inch are used for determining pressures while standard
characteristics are given in inches of mercury or inches of water. It is extremely important that the scale of such a gage
be of low range and finely divided if accuracy is desired. This is especially true of a gage reading in psi, the reading of
which is to be converted to inches of water. The following conversion factors may be helpful.
Inches of water = psi x 27.7"
Inches of mercury = psi x 2.04"
NOTE: Before starting the Run-In or starting the engine for any reason following an overhaul, it is of extreme
importance to observe the instructions on Preparation for Starting Engine First Time in Section 13.1.
The procedure outlined below will follow the order of the sample Engine Test Report.
1. Fill the lubrication system as outlined under Lubricating System -- Preparation for Starting Engine First Time in
2. Prime the fuel system as outlined under Fuel System-- Preparation for Starting Engine First Time in Section 13.1.
3. A preliminary valve clearance adjustment must be made before the engine is started. See Valve Clearance
4. A preliminary injector timing check must be made before starting the engine. See Timing Injector in Section 14.2.
5. Preliminary governor adjustments must be made as outlined in Section 14.
6. Preliminary injector rack adjustment must be made -- see Section 14.