63-18-02 HELIO: Amdt. 609 Part 507 Federal Register August 31, 1963. Applies to All Models H-391B, H-395 Serial Numbers 1 to 591, Inclusive, and H-395A Serial Numbers 1 to 1008, Inclusive.
Compliance required prior to September 15, 1963.
To preclude possible loss of engine oil through the vacuum oil separator due to blockage of the engine breather tube with ice or snow, accomplish the following:
Modify the oil breather tube P/N 391-060-317 by slicing a flute cut 18 inches from contour of lower cowl 0.25 to 0.31 inch depth and 0.75 inch in height on aft side of tube. This cut can be added to the present breather tube.
(Helio Service Bulletin No. 30A dated April 20, 1963, covers this same subject.)
This supersedes AD 62-12-05.
This directive effective September 1, 1963.