GENERATOR SET TEST AND INSPECTION AFTER REPAIR OR OVERHAUL
SECTION I. GENERAL REQUIREMENTS
12-1. GENERAL. The activity performing the repair or overhaul is responsible for the performance of all applicable tests
and inspections specified herein. Activities performing maintenance on any portion of the generator set must perform
those tests and inspections required by the applicable component or system repair instruction.
SECTION II. ENGINE RUN-IN AND DYNAMOMETER TEST
12-2. GENERAL. After overhaul, each engine must meet the minimum requirements set forth in paragraph 12-3, below.
Complete test data shall be recorded during each run, and performance evaluated at each phase of operation. At the
completion of the tests, a copy of the test log shall be attached to the engine. Engine testing shall be carried out with the
engine mounted in a separate dynamometer test cell. All brake horsepower (bhp) ratings shall be corrected to SAE
standard J816b conditions of 500 feet (152 m) altitude (29.00 inches (736.6 mm) Hg, dry barometer), 85°F (29°C) air
intake temperature, and 0.38 inches (9.7 mm) Hg water vapor pressure with number 2 diesel fuel VVF-800. Fuel
consumption data shall be based on a specific gravity of number 2 diesel fuel W-F-800 of 7.00 pounds per gallon (0.84
kg/L). At the completion of run-in and testing, the engine shall be mounted in the generator set for operational tests.
12-3. ENGINE RUN-IN AND DYNAMOMETER TEST.
a. Mount the engine to the dynamometer, and connect the test cell instruments and equipment (Figure 12-1).
Minimum instrumentation and equipment shall be as follows:
A manual engine speed control system (see paragraph 12-15).
For the instruments listed below, equivalent substitutes may be used provided compatible
instrument sending units are used at the appropriate engine pick-up points. The accuracy of
all instruments used in testing shall be in accordance with MIL-HDBK-705.
A tachometer to convert the magnetic pick-up PUI signal to rpm.
The crankcase blow-by tool 3375767 contains one plug and one Tee fitting. Both the plug and
Tee fitting have orifices of 0.354 inch (8.99 mm). Connect the plug and orifice to one breather
hose, and the Tee, orifice, and manometer to the other breather hose. Plug all other
crankcase openings to atmosphere.
A crankcase pressure manometer ST-1111 -3 and blow-by tool 3375767.
Coolant temperature gage 76-11229.
Two exhaust temperature indicators 80-7612.
Oil temperature gage 76-11228.
Oil pressure gage 76-11227.
Fuel rate measuring device (flow meter) ST-11 90.
Thermometer for recording ambient temperature at the air intake.
Connect the fuel tank to the fuel inlet filter system. The fuel used shall be in accordance with VV-F-800.
Connect radiator 80-7553, or equivalent, to the engine and fill the cooling system with a mixture of 50 percent
water and 50 percent antifreeze MIL-A-11755.