TM 5-3810-300-24&P-3
During normal engine operation, water vapor from the air
charge, as well as a slight amount of fuel and lubricating
oil fumes, condenses and settles on the bottom of the air
box. This condensation is removed by the air box
pressure through cored passages located at the front
and rear of the cylinder block with drain outlets (Fig. I) in
the side of the block.
Air box drains must be kept open at all times, otherwise
water and oil that may accumulate will be drawn into the
cylinders.
Inspection
A periodic check for air flow from the air box drain tubes
should be made (refer to Section 15.1).
Fig. 1-Air Box Drain Tube
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