TM 5-3895-359-14&P
Check the normal air intake vacuum at various speeds
findings in the Basic Run-in, the entire Basic Run-In
(at no-load) and compare the results with the Engine
must be repeated as though the Run-In and test
Operating Conditions on Page 10-9-1. Record these
procedure were started anew.
readings on the Engine Test Report.
All readings observed during the Final Run-In should fall
Check the exhaust back pressure at the exhaust
within the range specified in the Operating Conditions on
manifold companion flange or within one inch of this
Page 10-9-1 and should be taken at full load unless
location. This check should be made with a mercury
otherwise specified. Following is a brief discussion of
manometer through a tube adaptor installed at the
each condition to be observed.
tapped hole. If the exhaust manifold does not provide a
1/8" pipe tapped hole, such a hole can be incorporated
The engine water temperature should be taken during
by reworking the exhaust manifold. Install a fitting for a
the last portion of the Basic Run-In at full load. It should
pressure gage or manometer in this hole. Care should
be recorded and should be within the specified range.
be exercised so that the fitting does not protrude into the
stack. The tapped hole must be in a comparatively
The lubricating oil temperature reading must be taken
straight area for an accurate measurement.
The
while the engine is operating at full load and after it has
manometer check should produce a reading in inches
been operating long enough for the temperature to
that is below the Maximum Exhaust Back Pressure for
stabilize. This temperature should be recorded and
should be within the specified range.
the engine (refer to Page 10-9-1).
The lubricating oil pressure should be recorded in psi
Refer to the Final Engine Run-In Schedule and
after being taken at engine speeds indicated in the
determine the maximum rated brake horsepower and
Operating Conditions, Page 10-9-1.
the full-load speed to be used during the Final Run-In.
Apply the load thus determined to the dynamometer.
The fuel oil pressure at the fuel manifold inlet passage
The engine should be run at this speed and load for 1/2
should be recorded and should fall within the specified
hour. While making the Final Run-In, the engine should
range. Fuel pressure should be recorded at maximum
develop, within 5%, the maximum rated brake
engine speed during the Final Run-In.
horsepower indicated for the speed at which it is
operating.
Check the air box pressure while the engine is operating
at maximum speed and load. This check may be made
If this brake horsepower is not developed, the cause
by attaching a suitable gage (0-15 psi) or manometer
should be determined and corrections made.
(15-0-15) to an air box drain or to a hand hole plate
prepared for this purpose. If an air box drain is used as
When the above conditions have been met, adjust the
a source for this check, it must be clean. The air box
maximum no-load speed to conform with that specified
pressure should be recorded in inches of mercury.
for the particular engine. This speed may be either
higher or lower than the maximum speed used during
Check the crankcase pressure while the engine is
the Basic Run-In. This will ordinarily require a governor
operating at maximum Run-In speed.
Attach a
adjustment.
manometer, calibrated to read in inches of water, to the
oil level dipstick opening. Normally, crankcase pressure
All information required in Section "E", Final Run-In, of
should decrease during the Run-In indicating that new
the Engine Test Report should be determined and filled
rings are beginning to "seat-in".
in. After the prescribed time for the Final Run-In has
elapsed, remove the load from the dynamometer and
Check the air inlet restriction with a water manometer
reduce the engine speed gradually to idle speed and
connected to a fitting in the air inlet ducting located 2"
then stop the engine. The Final Run-In is complete.
above the air inlet housing.
When practicability
prevents the insertion of a fitting at this point, the
F. INSPECTION AFTER FINAL RUN-IN
manometer may be connected to a fitting installed in the
After the Final Run-In and before the Engine Test
1/4"pipe tapped hole in the engine air inlet housing.
Report is completed, a final inspection must be made.
This inspection will provide final assurance that the
The restriction at this point should be checked at a
engine is in proper working order.
During this
specific engine speed. Then the air cleaner and ducting
inspection, the engine is also made ready for any brief
should be removed from the air inlet housing and the
delay in delivery or installation which may occur. This is
engine again operated at the same speed while noting
accomplished by rustproofing the fuel system as
the manometer reading. The difference between the
outlined on Page 10-11-28 and adding a rust inhibitor
two readings, with and without the air cleaner and
into the cooling system (refer to Page 10-9-14). The
ducting, is the actual restriction caused by the air
lubricating oil filters should also be changed.
cleaner and ducting.
10-9-6
