TM 5-3810-300-24&P-3
Run-In Instructions 13.2.1
should decrease during the Run-in indicating that new
E. FINAL RUN-IN
rings are beginning to "seat-in".
After all of the tests have been made and the Engine
Check the air inlet restriction with a water manometer
Test Report is completed through Section "D", the engine
connected to a fitting in the air inlet ducting located 2"
is ready for final test. This portion of the test and Run-in
above the air inlet housing. When practicability prevents
procedure will assure the engine owner that his engine
the insertion of a fitting at this point, the manometer may
has been rebuilt to deliver factory rated performance at
be connected to a fitting installed in the "pipe tapped
the same maximum speed and load which will be
hole in the engine air inlet housing. If a hole is not
experienced in the installation.
provided, a stock housing should be drilled, tapped and
If the engine has been shut down for one hour or longer,
kept on hand for future use.
it will be necessary to have a warm-up period of 10
The restriction at this point should be checked at a
minutes at the same speed and load used for warm-up in
specific engine speed. Then the air cleaner and ducting
the Basic Run-In. If piston rings, cylinder liners or
should be removed from the air inlet housing and the
engine again operated at the same speed while noting
the Basic Run-In, the entire Basic Run-In must be
the manometer reading. On turbocharged engines, take
repeated as though the Run-in and test procedure were
the reading on the inlet side of the turbocharger. The
started anew.
difference between the two readings, with and without
All readings observed during the Final Run-In should fall
the air cleaner and ducting, is the actual restriction
within the range specified in the Operating Conditions in
caused by the air cleaner and ducting. Check the normal
Section 13.2 and should be taken at full load unless
air intake vacuum at various speeds (at no-load) and
otherwise specified. Following is a brief discussion of
compare the results with the Engine Operating
each condition to be observed.
Conditions in section 13.2. Record these readings on
the Engine Test Report.
The engine water temperature should be taken during
the last portion of the Basic Run-In at full load. It should
Check the exhaust back pressure at the exhaust
be recorded and should be within the specified range.
manifold companion flange or within one inch of this
location. This check should be made with a mercury
The lubricating oil temperature reading must be taken
manometer through a tube adaptor installed at the
while the engine is operating at full load and after it has
tapped hole. If the exhaust manifold does not provide a
been operating long enough for the temperature to
/8" pipe tapped hole, such a hole can be incorporated by
stabilize. This temperature should be recorded and
reworking the exhaust manifold. Install a fitting for a
should be within the specified range.
pressure gage or manometer in this hole. Care should
be exercised so that the fitting does not protrude into the
The lubricating oil pressure should be recorded in psi
stack. On turbocharged engines, check the exhaust
after being taken at engine speeds indicated in the
back pressure in the exhaust piping 6" to 12" from the
Operating Conditions, Section 13.2.
turbine outlet.
The tapped hole must be in a
comparatively
straight
area
for
an
accurate
The fuel oil pressure at the fuel manifold inlet passage
measurement. The manometer check should produce a
should be recorded and should fall within the specified
reading in inches that is below the Maximum Exhaust
range. Fuel pressure should be recorded at maximum
Back Pressure for the engine (refer to Section 13.2).
engine speed during the Final Run-In.
Refer to the Final Engine Run-In Schedule and
Check the air box pressure while the engine is operating
determine the maximum rated brake horsepower and the
at maximum speed and load. This check may be made
full-load speed to be used during the Final Run-In. Apply
by attaching a suitable gage (0-15 psi) or manometer
the load thus determined to the dynamometer. The
(15-0-15) to an air box drain or to a hand hole plate
engine should be run at this speed and load for hour.
prepared for this purpose. If an air box drain is used as
While making the Final Run-In, the engine should
a source for this check, it must be clean. The air box
develop, within 5%, the maximum rated brake
pressure should be recorded in inches of mercury.
horsepower indicated for the speed at which it is
operating. If this brake horsepower is not developed, the
Check the crankcase pressure while the engine is
cause should be determined and corrections made.
operating at maximum Run-in speed.
Attach a
manometer, calibrated to read in inches of water, to the
When the above conditions have been met, adjust the
oil level dipstick opening. Normally, crankcase pressure
maximum no-load speed to conform with that
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