Air box drains must be kept open at all times, otherwise
water and oil that may accumulate will be drawn into the
A periodic check for air flow from the air box drain tubes
should be made (refer to Page 10-11-6).
Fig. 1. Air Box Drain Tubes
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
the air box pressure through cored passages located at
the front and rear of the cylinder block with drain outlets
in the side of the block (Fig. 1).